Talk:Microwave oven/Archive 4

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Archive 3

Archive 4

Archive 5

Silver cardboard inside the microwave?

I have a microwave, new, that has a piece of silver cardboard (which flakes) that is detachable from an opening in the top of the inside of the microwave ... what is it?

I'm afraid to use the microwave with or without it.

-G —Preceding unsigned comment added by 76.67.114.84 (talk) 04:26, 15 August 2008 (UTC)

I have no idea what tis is, it might be a good idea to read the manual. Lars T. (talk) 20:24, 15 August 2008 (UTC)

Split microwave oven into microwave oven and microwave heating

This article is getting rather long. I think it might benefit from being slitted into microwave oven and microwave heating. The former will emphasize the domestic and culinary uses of a microwave oven, while the latter will delve deeper into the theoretical background and deal with industrial and scientific usages such as textile drying or analytical chemistry. Does it sound like a good idea? --Tunheim 10:05, 30 January 2007 (UTC)

Keep it as one article. The background science is often what people want to know if they are looking up "microwave oven". Manassehkatz 15:00, 30 January 2007 (UTC)

Would you then be comfortable with having sections on textile drying or analytical chemistry in the microwave oven article? --Tunheim 17:09, 30 January 2007 (UTC)

I would be comfortable with that as long as the devices used for such activities are considered "ovens" in some reasonable sense. From the beginning of the oven page: "An oven is an enclosed compartment for heating, baking or drying." This is not exclusive to heating of food, and I don't think Microwave Oven needs to be a food-only page. Manassehkatz 23:25, 30 January 2007 (UTC)

Well, some of these devices would probably not be considered ovens in any but the most liberal use of the word. However they would fit nicely under the heading "microwave heating", a heading that currently redirects to "microwave oven".

I guess I just realized that I never stated that the reason for the split is that "microwave heating" redirects to "microwave oven"? Does my proposal make more sense considering this? --Tunheim 07:20, 31 January 2007 (UTC)

I also vote keep this as one article and not split it. —Lowellian (reply) 00:08, 14 February 2007 (UTC)

This is not a poll. This is a discussion. Please provide a rationale for your opinion. --Tunheim 16:55, 14 February 2007 (UTC)

Microwave heating might clarify some science and other applications missed by this article (the actual interaction with water, heat guns, etc). But most of what's here is in the context of debunking myths and giving warnings for actual microwave ovens. So this article is pretty focused on the title. Maybe there's room for another article. But microwave heating and microwave cooking are two different things, and accidental microwave heating of things which are not to be cooked should be covered in microwave oven. Potatoswatter 08:17, 17 February 2007 (UTC)

I say spilt it for when I looked it up I was really looking for the invention and developement behind the microwave rather than the 'how it works' side of things. —Preceding unsigned comment added by 219.89.69.245 (talk) 08:51, 5 September 2007 (UTC)

The split would allow the "microwave heating" article to address other applications of microwave heating (e.g., termite control) that just seem out of place in a "microwave oven" article.
—Darin McGrew 05:40, 28 October 2007 (UTC)

I agree on the split also, the majority of searchers are probably expecting information about the small appliance when they look at this article. The more industrial and scientific content can be put in the heating article. Eli lilly 15:32, 3 November 2007 (UTC)

When I got an Astronomy qualification (At the age of 12!) I needed to access information about things like Microwave Energy without having to trawl through pages of text on Microwave Ovens. It would be easier to keep them as two separate subjects so people can access information quicker. Dan Tucker 21:45, 9 December 2007 (UTC)

I don't see the need to separate it, even after reading opinions of others, and if it does happen, I have heard of microwave heat possibly causing cancer, and wikipedia would help convince me. So, please include that in the section. Alyssa G., 22 Jan 08

Indeed, I agree with you Dan, splitting it up will make it easier for people to access the information they want. And I would call those pages "Microwave heating" and "Domestic microwave oven" to distinguish them more clearly. It should have an overview of the safety issues, with a link to the "Microwave heating" article, which should go into the issues in more detail. Just "Microwave oven" would also refer to industrial applications and that's not what we want. BDWBrussels 17:50, 29 May 2008

I agree that the article should be split, with the "Microwave oven" or "Domestic microwave oven" article focusing on the use of the microwave, preferably including a section on the features that are generally included on a microwave. That's what I was looking for, specifically the beeping noise that many microwaves make when one presses a button. I think that the split would allow the two articles to each be more focused; right now, the article seems without direction, discussing both the appliance and the science behind it. I also agree that the eventual "Microwave oven" article should have a section on the history of the appliance.Kleio08 (talk) 15:36, 12 June 2008 (UTC)

I'm concerned that splitting the article would fragment it too much, resulting either in duplicate information or having to read both articles at the same time to get useful information. I might support it if there could be some assurance that Microwave Heating would be strictly limited to the chemistry, physics, and thermodynamics behind microwaving (the current "Principles" section, with Microwave Oven covering everything else. I just don't see enough material to justify a complicated split, and unless you limit the new article to the current contents of the Principles section I don't see there being a clean split between Domestic Microwave Oven and the rest of the article. This is particularly since there seems to be little material on microwave heating that is not in the confines of a domestic microwave oven. --TexasDex ★ 20:14, 24 June 2008 (UTC)

I've closed this as there is already a Dielectric heating article. Feel free to move things about. --SesquipedalianVerbiage (talk) 11:48, 18 July 2008 (UTC)

Putting live animals in microwaves

Shouldn't there be something in the Safety and controversy section that says that live animals should never be put into a microwave, and the effects of what happens if they are (ie. death)? I know it's painfully obvious but an encyclopedia is supposed to assume the reader is completely ignorant of the subject matter. 65.40.239.99 03:13, 7 February 2007 (UTC)

People that do such stupid things never read things like this anyway. Nevertheless i added Added Microwave_oven#Heating_of_living_tissue. Now a reader has to be both ignorant, unable to follow simple logical deductions and completely devoid of common sense. --Tunheim 07:43, 7 February 2007 (UTC)

Or sadistic. Or just morbidly curious. Potatoswatter 08:19, 17 February 2007 (UTC)

Neither of which contradicts Wikipedia:Five pillars. So go ahead, be bold! :-) --Tunheim 17:53, 17 February 2007 (UTC)

I changed the title of the section. It's about inserting animals into the microwave, not about heating living tissue. Malamockq 15:33, 21 March 2007 (UTC)

This section is completely unnecessary. It lacks citation, smells of OR, and is both unencyclopedic and instructional. See: WP:BEANS. I'm pressing for its removal. -Etafly 14:48, 28 April 2007 (UTC)

Good call. This section is rubbish. I'm sure the convection oven article doesn't have a similar section, nor does the blender. There are a lot of things one "shouldn't do with live animals", but it's ridiculous to remind people in an encyclopedia. -Mikeeg555 06:10, 30 April 2007 (UTC)

• Removed. -Etafly 06:41, 30 April 2007 (UTC)

I don't think it needs it's own section, it could be stated somewhere, just not have a section devoted to the outcomes of putting an animal in the microwave ! —Preceding unsigned comment added by 24.91.92.76 (talk) 21:32, 22 January 2008 (UTC)

Gak! See WP:BEAN. SBHarris 23:23, 22 January 2008 (UTC)

ARAD Missile Decoy

I have heard that during the NATO intervention there, Serbian SAM gunners would take a few microwave ovens, wire around the safety interlock and run them with their doors open. This would decoy off HARM missiles quite effectively (some Serbian missile sites had over a hundred HARMs fired at them without effect), presumably provided they turned off their actual radar in time. Finding a source for this may be entertaining. Kensai Max 06:12, 8 March 2007 (UTC)

Could be true. But could just as easily be an urban legend. But I agree: Finding a source could be entertaining. --Tunheim 18:22, 18 March 2007 (UTC)

I used to work on radar systems for the military, and although I don't know what frequency HARM missles seek in on (possibly a multitude), but I would assume that a HARM would lock onto the "strongest signal." I would think that a radar-emitting station (such as the ones that the HARM was designed for) would emit FAR more radiation than what a microwave put out. If a radar site disabled their radar system, the HARM missile would have missed anyway. Incidentally, I watched a Mythbusters episode (currently playing on the Discovery Channel, don't kill me if I've violated a copyright/trademark) in which the participants were trying to find a way to defeat a Police radar, which operates at 12.5 GHz I believe. The jury-rigged microwave ovens were mounted to the front of a car with the doors open, turned on, and driven down a runway with a police radar gun pointed at it. They did not even faze the radar gun at all...in fact, the gun got a faster lock than when the car had no microwave headlights. --Perfectapproach 17:17, 20 June 2007 (UTC)

Which isn't too surprizing, compare an open microwave oven to a corner reflector. Lars T. 17:57, 20 June 2007 (UTC)

I just had to comment on the item about the police car experiment. I attended a college in Vancouver around 1964 and in there we had a radar assembly from a CF-100 mounted on a rolling rack so that it could be pointed out the window and aimed across the harbor. It was pretty impressive. Anyway, one day some of the students noticed a cop with traffic radar set up. They aimed the unit down toward him and he started to whack at the side of "his" radar unit. Apparently the boys in the class must have fried the mixing diodes in the cops radar unit. I imagine that the pulse power of the aircraft radar must have been way higher than the output from a microwave oven and a lot more focused. I'm innocent I tell 'ya, I just got to hear about it after the fact (after the damage was done).

Safety Measures -> Pregnant Women?

Some microwaves include a remote control or a button "start after... minutes", especially useful for pregnant women.

I fail to see(/the article fails to explain) how a remote control or a "start after X minutes" feature is a safety measure, much less how it pertains specifically to pregnant women. Could someone care to either clarify or delete this reference? --RealGrouchy 04:12, 21 March 2007 (UTC)

You won't receive an explanation to this -- it's simply rubbish. --Tunheim 07:45, 21 March 2007 (UTC)

It gives you a chance to get away from the door of the oven

where most of the radiation comes out. I have a friend

(we're both scientists) whose head hurts if he does not get

away from the microwave oven before the magnetron actually comes

on (which is about one second after hitting start on his oven).

The safety issue is real. See e.g. Bohr & Bohr, Phys Rev E

http://prola.aps.org/abstract/PRE/v61/i4/p4310_1

which shows that microwaves can unfold proteins without

heating them. If certain proteins unfold and then misfold,

you get Alzheimer's or Parkinson's.

The first big rise in the rate of Alzheimer's was between

1979 and 1986, when microwaves became popular in the US.

The next big increase started in 2000 after cell phones became

popular.

Physicsjock 11:15, 14 September 2007 (UTC)

The above needs help from an expert (and so does the page on aluminium foil, for similar reasons). Could someone who works, say, for OSHA, Consumer Reports, or Underwriters Lab please help? This is a topic which really needs expert opinion, because the wrong information potentially could harm someone. I'm not taking a stand, however regarding the above statements:

The "Start After" feature is probably intended to do cooking when someone is not at home, or when several dishes need to be timed to arrive at a similar time. The idea that someone can "get away" seems like it might cause accidents ... imagine a pregnant woman trying to "get away" from something in a hurry ... to some ill-defined distance.

Since microwaves only penetrate to a limited extent, even if it was true (the child of) a pregnant woman was affected, would it only be after the first trimester, when the child was near enough the surface?

The examples by Physicsjock are perhaps important, but they are confusing. It's not legitimate to use a friend's headache as proof -- they might be imagining a reaction, they might be sensitive to some other part of the microwave, they might have a special medical condition, or a medical implant. The article that's cited is highly technical, and is not available in full without payment. What the article says which is directly related to the subject is that microwaves *may* have implications for biological systems. But it doesn't say anything about what the implications are.

There is strong financial incentive for microwave and cell phone makers to make claims there are no ill effects. And there's a natural suspicion that a high-tech technology may have negative effects which have not yet been discovered. This article needs a voice from someone who can demonstrate they are in neither camp.

Alpha Ralpha Boulevard (talk) 05:22, 22 April 2008 (UTC)

Off-center placement

Off-center placement != even heating, say I. The main page claims that placing food in the exact center of the turntable defeats its purpose. It implies that even heating is created by making sure the food moves all around the inside of the microwave cavity, such that it experiences a nice variety of microwave field strengths. By even heating I assume we mean heating all sides of the food evenly (Heating the inner parts of food evenly with the outer parts of the food is a different issue that has nothing to do with the turntable). I'm also assuming that we all agree that the way to achieve the highest level of evenness is to have all parts of the food experience the same levels of microwave field strength for equal amounts of time. If the field strength within the cavity of the microwave were even throughout, then this would be a non-issue. You could just sit it still anywhere inside and heating would be even. But assuming it varies depending where you are in the cavity, then it seems obvious to me that the way to make sure all sides of the food get exactly the same experience during cooking, is to keep the food in exactly the same position (therefore ensuring that it is immersed in the exact same microwave field environment the whole time) while rotating the food such that every side of the food spends exactly the same amounts of time in the various possible positions and field strengths. If you place the food off-center, then it becomes possible that every time the food is facing left, the left side of the food is in a different field strength than the right side of the food experiences when the food is facing right. If the food were centered, then every side of the food would pass through the exact same field patterns on every spin cycle, thus ensuring exact evenness.

Am I missing some phenomenon that would make off-centered placement somehow more egalitarian than centered placement?

—Preceding unsigned comment added by Mholveck (talk • contribs) 16:53, 26 March 2007

I concur...assuming (doubtfully) there was a "cold spot" in the very centre of the oven, a very small item might be heated faster by being placed off-centre, but in being very small, it should then also receive even (if slower) heating within that "cold spot". Normal sized items, however, should be able to rotate through multiple hot/cold spots regardless of where on the turntable they are placed. I think the "off-centre=even-heating" in the article may sound like a bit of original research...Mikeeg555 13:05, 2 April 2007 (UTC)

It doesn't matter whether the center of the turntable is a "hot spot" or a "cold spot"; the point is that any food that occupies the exact center of the turntable will only be exposed to that one spot. If you place your food so that none of it occupies the center of the turntable, then all of the food will receive a variety of different radiation patterns and no portion of the food will be permanently subject to just one pattern. Atlant 13:16, 2 April 2007 (UTC)

Assuming a regular multimode cavity microwave oven, imagine an 10 mm radius area around the central point of a rotational platter in the cavity. Further assume that this area has a field density significantly higher than the surrounding area. Imagine placing a block of butter in the center. In such a case a hole will be melted in the butter. However, if the butter was placed a few centimetres off/center this would not happen. This is another way of stating what Atlant stated above. I encourage everyone with a spare block of butter to try this out. --Tunheim 11:38, 8 April 2007 (UTC)

Too much criticism

About 50% of the article is devoted to criticism and large parts of it are either poorly written or unsourced. We should aggressively remove such items to improve the balance of the article. Chris Cunningham 13:22, 5 April 2007 (UTC)

How about you just add more "good" stuff? I'm interested in reading the criticism. —The preceding unsigned comment was added by 72.189.34.23 (talk • contribs).

Yep, add more good stuff rather than complain about the critism. Lacking sources?, look them up. Electron9 (talk) 15:00, 16 February 2008 (UTC)

Picture

Why can't we ever get a normal picture of something? I mean, the microwave looks like it's stuck under the cupboard. Ah, forget it, I'm just here to blow off some steam. - Uagehry456 03:01, 10 April 2007 (UTC)

Soviet ban & Swiss Research

I thought these should be mentioned since I've found numerous mentions of them on the Internet (eg http://www.relfe.com/microwave.html). Some of the Soviet research sounds worrying to me, especially the production of carcinogens. I wonder if there is any connection with research which shows carcinogenic Acrylamides being produced when starchy foods are subjected to high heat?

I've read that the Soviet ban was lifted "after Peristroika", but I haven't found anything which explained what scientific justification, if any, was given for lifting the ban. I wonder if the Russian language version of Wikipedia has more information?

81.98.208.169 21:44, 24 April 2007 (UTC)

The Soviet ban is commonly cited in microwave literature as an example of over zealous radiation protection that later proved uncalled for. The strict soviet limits were only in existence for around ten years, before it was realized how they were way too strict. --Tunheim 06:16, 25 April 2007 (UTC)

I think cited is a too strong word, mentioned is correct, but I have still to see any more definitive source of this claim. I have also seen (unsourced) discussions that the cause of the ban was not due to radiation protection, but due to the fact that it is fairly easy to convert a microwave oven to a radio transmitter, something that was heavily controlled in the soviet union. Mossig 09:05, 25 April 2007 (UTC)

I am not going to get into a battle about this entry. This will be my last comment.

Wikipedia is supposed to be a source of information. Removing information about the Soviet ban & the Swiss researchers does not improve Wikipedia. It reduces its usefulness and authority.

I had hoped that critics would add to the information by giving proper scientific reasons for why the ban was lifted & why the Swiss research did not carry weight in the general scientific community. Tunheim's explanation is extremely vague.

81.98.208.12 11:11, 25 April 2007 (UTC)

But Wikipedia isn't a vehicle to help disseminate any old rumour, urban legend, or scare. Without adequate references, that's exactly what this new information sounds like. We can still debate whether cell phones cause brain cancer; the jury's not really "in" on that one yet, but after 40 years of use of microwave ovens, we can be reasonably certain that the hazards of the ovens are pretty-well understood and bounded.

Given adequate citations and context, there's no reason your bew material can't stay. But without support and context, it can't remain in the form in which you inserted it.

Atlant 12:13, 25 April 2007 (UTC)

I removed the text in discussion, as the submitter in the preceeding discussion said (more or less) that he would not give any sources to them. I have looked over the web, and the only sources to these statements I find is scaremongering quasi-scientific sites. I will be glad to add the statements back into the article again when releveant references are given. (The statement on the Soviet ban should be relativly easy to veriy, asp. if anybody knows russian?) Mossig 19:13, 25 April 2007 (UTC)

According to works of Metaxas [1] and Meredith [2] there was a short lived Soviet ban (or rather: very strict radiation limits) some decades ago. I believe this to be a fact. The reasons behind the ban, I don't know. However, since the ban was lifted after few years, I can only assume the reasons for the ban were found to be wrong, lacking or in some other way flawed. --Tunheim 09:57, 26 April 2007 (UTC)

Any more detailed references to this? Mossig 19:21, 20 May 2007 (UTC)

microwave oven efficiency vs. conventional ovens

Just a thought - it might be hard for the average person to understand that the 65% efficiency of a home microwave is actually amazingly good... perhaps someone could estimate or give an example of the efficiency of an electric oven in heating one pound of food to 350°? It's probably well under 5% I'd imagine. Inlinesk8er 00:48, 10 May 2007 (UTC)

Would it be correct to state most microwave ovens are ~65% efficient? I've figured my 1000W oven is nearly identical in efficiency to the 700W oven mentioned in the article. - MSTCrow 20:48, 8 August 2007 (UTC)

I second the suggestion regarding adding effciency of "calrod" based ovens, I specifically delved into this discussion to see if there was a mention of it.DGerman 16:00, 6 October 2007 (UTC)

James Lovelock

Why is there no reference to James Lovelock as one of the creators of the microwave oven? He was the first person to have a microwaved potato in the 1940s. He did not patent his invention because magnetrons were quite expensive then.

Any references to this? The only documentation I find on his homepage (http://www.jameslovelock.org/) is the claim that he has invented the microwave oven, and an article from 1955 (The microwave oven was patented in 1945): "# Andjus, R.K. and Lovelock, J.E. 1955. Reanimation of rats from body temperatures between 0 and 1 C by microwave diathermy. J. Physiol.,". Mossig 19:22, 20 May 2007 (UTC)

Schematic/diagram

is missing from article, making it less clear than desired (and yes, i'm for split too) —Preceding unsigned comment added by 83.149.9.176 (talk) 05:31, 2 February 2008 (UTC)

Incorrect/arranged picture ..??

A microwave oven with a metal shelf

This picture seems incorrect. Metal + microwave oven => Bzzzz, unless one pays really careful attention to standing wave node point locations. Electron9 (talk) 14:56, 16 February 2008 (UTC)

I dunno as I can heat up those cans of soup with a rim of metal around it, but foil is, as you so correctly put it, "bzzzz." We still have a line in our microwave from when foil was in there and it heated up so much that when it touched the plastic, it burnt it. Maybe it's the type of metal?-Babylon pride (talk) 19:24, 22 February 2008 (UTC)

What is the purpose of this picture? Is it ok to place metallic grills inside a microwave oven? —Preceding unsigned comment added by 59.178.50.13 (talk) 07:05, 25 March 2008 (UTC)

Some microwaves do come with these metal grills that fit in grooves in the side of the microwave. They allow you to heat more food at once, particularly when you need to keep two plates of food warm. They don't cause the microwaves any problems at all, but I don't know why that is. Maybe we should get a chemist to explain why, and what the distinction is. Has anyone checked the Microwave article? We might also want to add the explanation under "variants and accessories." Kleio08 (talk) 15:28, 12 June 2008 (UTC)

Its safe to place large or thick metal objects into the microwave. The reason that wires or foil spark is because the microwaves turn into electrical energy when they are absorbed by the metal. The foil cant hold much electricity and so releases it by sparking when the energy builds up enough whereas thick metal dosnt. Also i am for the split and sugest that there should also be a seperate article that deals with the health effects of microwaves, effects on proteins, tissue, cancer, pregnant women, ect. And a section that explains how microwaves interact with different substances and the occurence of plasma in the microwave when a flame is placed inside. I would like scientific explanations to the microwave interactions because i have not been able to find good explanations and it is relevant to microwave energy. Incredibleman007 (talk) 16:25, 9 July 2008 (UTC)

"Effects on food and nutrients" has no content

The section "Effects on food and nutrients" starts out by saying that studies have shown both positive and negative effects from microwave heating. However, it doesn't go on to say what was found. It just lists a bunch of articles. Many of the articles don't tell you the conclusions in the title, e.g. "Nutritional effects of microwave cooking." Would it be too difficult to summarize the contents of those articles, like someone did for the first one? At this rate, we'll just have a list of references instead of articles. — Sam 20:05, 7 April 2008 (UTC)

microwaving food depletes it of its nutrients: http://www.relfe.com/microwave.html —Preceding unsigned comment added by 99.132.138.64 (talk) 23:28, 22 July 2008 (UTC)

Here is an article on microwave ovens and nutrients along with an microwaved water experiment Dangers of Microwaving your food WSNRFN (talk) 22:33, 15 August 2008 (UTC)WSNRFN

That article, and the so-called experiment, are awful and nothing but scaremongering masquerading as science. Verbal chat 06:50, 16 August 2008 (UTC)

Clarity issue -- needs adjustment

In the Principles section, the explanation of why the microwave radiation cannot exit through the conductive mesh on the viewing window is not clear. "Because the size of the perforations in the mesh is much less than the wavelength of 12 cm, most of the microwave radiation cannot pass through the door..." is the explanation given. However, the axis of motion of the radiation (direction the waves are traveling), and therefore the wavelength, is through (normal to) the door. But the perforations are on the same plane as the door. So, to a normal reader, the diameter of the perforations seems unrelated to the wavelength. It is therefore suggested that this explanation be expanded on. —Preceding unsigned comment added by Candlefrontin17 (talk • contribs) 13:30, 9 June 2008 (UTC)

Inaccurate statement in introduction

I noticed the following phrase, in regard to microwave cooking, in the article's introduction: "leading to food being adequately heated throughout (except in thick objects), a feature not seen in any other heating technique."

A feature not seen in any other heating technique? Really? If I boil pasta in water on the top of my stove it comes out adequately heated throughout. If I roast a chicken in my conventional oven for an hour it comes out adequately heated throughout. Same with bread from my toaster, eggs in a frying pan and hot dogs cooked on a stick over a campfire.

Frankly, the phrase in question is a dumb statement...or at very least, a highly misleading one. If enough people agree, I'd like to see it changed. —Preceding unsigned comment added by 65.25.124.205 (talk) 15:38, 2 January 2010 (UTC)

removed paragraph requires rework

The following paragraph was removed as being poorly integrated into the text.

• Please Note: This information is not up to date, see 'Even-Heating Microwave Technology' article by author Gordon T. Andrews of GAMA Microwave Technology Ltd., published in the US Appliance magazine Engineering section dated March 2007 .. Quote: A new microwave technology was designed to produce even verticle and lateral heating distribution, regardless of shelf position, and is reportedly unaffected by the use of metal baking utensils without sparking. This new microwave technology has since been introduced in multiple (10) metal shelf catering foodservice combination-steamers and convection bake-off oven, as well as consumer cookers.

Some note of this presumably should be added to the article, but this is not acceptable form, as articles are not supposed to be collections of isolated references, but a seamless account of the topic. ww (talk) 13:13, 27 June 2008 (UTC)

Cannot be recycled

Should it be mentioned in the article? Imagine Reason (talk) 20:27, 9 July 2008 (UTC)

Cathode ray tube does mention recycling, toxicity, and other material dangers. (A very well-done article, btw.) The battery article also mentions disposal. That would seem to suggest there would be a place for a short section on disposal, here. Alpha Ralpha Boulevard (talk) 20:38, 31 July 2008 (UTC)

microwave ovens and the ISM band

Which came first -- the ISM band allocation, or the microwave oven? Please help us find out at Talk:Electromagnetic compatibility#ISM bands. --68.0.124.33 (talk) 04:13, 14 July 2008 (UTC)

English dialect

For the purposes of WP:ENGVAR, which variety of English is the "original variety" of English for the microwave oven article[3]? --68.0.124.33 (talk) 04:11, 21 July 2008 (UTC)

It's been in US English up until now AFAIK. Chris Cunningham (not at work) - talk 09:12, 21 July 2008 (UTC)

Well, I do prefer British/Commonwealth/International English - but the problem here was I had my usual GB-en spellchecker on rather than switching to US-en. Apologies. --SesquipedalianVerbiage (talk) 09:14, 21 July 2008 (UTC)

Mechanism

Explain how microwaves convert electric power to microwave radiation. —Preceding unsigned comment added by 192.174.37.51 (talk) 21:02, 13 August 2008 (UTC)

This is more likely to be a good fit to the magnetron or microwave articles, not in this one, about a cooking tool. Or perhaps the reference desk. ww (talk) 15:25, 19 August 2008 (UTC)

Heating Water

I removed the blip about water heating the best in a microwave because it needs clarification (and was already marked as needing citation, and since I pretty much know it is incorrect). While water may be the "heat source" for most foods cooking in a microwave, it is certainly not the "most efficient" heater, especially when you are talking about say, a cup of pure water. For example, a cup of water and a cup of milk at the same temperature, the milk will boil first. My theory (with no references to back it up) is this is because all the water molecules are experiencing the dielectric effect at almost the exact same moment, so not as much heat occurs as when they are intermixed with other molecules which do not exhibit the effect to the same degree.Jasonkeirstead (talk) 11:03, 28 August 2008 (UTC)

What heats "best" is not a very clear thing. Water absorbs energy better, but it may not heat as fast, simply because it doesn't have as large heat capacity, so it absorbs more energy but doesn't go up as much in temperature.

As an example, I had to try your milk experiment, so I took two 80 mL samples of water and milk in identical beakers and and stuck them here into the lab kitchen GE microwave, both thermocouple measured at exactly 24.5 C before they went in. After 10 seconds on "high" (both of them together, placed at exactly equal spots on either side of the rotating table, equidistant from center to edge) the water had gone up 7.3 C and the milk 7.8 C after taking them out and mixing and letting them equilibrate for a couple of minutes. Ha, the milk was heating 6.8% faster. And my microwave was putting out about a bit more than 500 watts, which is about right. After another shot of 15 seconds (I made sure the milk and water traded places on the rotating glass bottom for this one) the milk heated by 12 C to a total of 44.3 C, and the water heated by 11.4 C to a total of 43.2 C. So again, the milk is heating 5.2% faster. (And both samples heated about 50% more, in keeping with the 50% increase in time, so the experiment is going well).

But hold on, there! First, I have a total of 19.8 C heating for the milk, and 18.7 C heating for the water, so on average, the milk beat the water in heating by only 19.8/18.7 = 1.059 = 5.9%. Not much! I can't reliably measure volumes in beakers that well! (I should have used a graduated cylinder, but I'm ruling out first order effects). Second, there's a bigger problem, which is that milk isn't pure water. I used skim milk, which has 13 grams of sugar and 9 grams of protein in 240 mL (according to the label) so it's only about 91% water. So it's not surprising if it only has 1/1.059 = 94.4% of the heat capacity of pure water. All that is required is that the milk solids, the sugar and protein, have 3.3/9 = 37% of the specific heat capacity of the water they replace in the milk. Which isn't hard to believe at all, since water has so high a specific heat capacity. So, all in all, we're both doing original research, but the effect you report is very small, and is easily explained by the fact that water has a higher specific heat capacity than the stuff you're replacing it with, in a food-mix, or even in milk. But the water is doing most of the microwave absorption, just as advertised by the texts. SBHarris 04:08, 21 January 2009 (UTC)

While I;m shocked, Shocked, JUST SHOCKED, I say!! to see original research appearing on WP, I must congratulate Sbharris on his demonstration. Well reasoned, well planned, well analyzed. And probably didn't take all that long either. Good job. Too bad WP can't use it. Although, now having been published.... ww (talk) 13:21, 2 April 2009 (UTC)

interesting research! Also remember that deionized water boils slower than salted water (or probably mineral=salts=ion rich milk), not so much because of dipole changes, but because of the second heating mechanism by microwaves: ion -> charge movement.. --132.230.191.208 (talk) 13:14, 3 February 2010 (UTC)

Superheating liquids and the MythBusters

I reverted a change that claimed that only distiled water could superheat in a microwave oven based on a MythBusters episode. Not only does the reference in the article handle that myth, not even the MythBusters claim that, they only compare distiled water (that will always superheat) to tap water (that will always boil). At the end of the segment, Adam Savage specifically says that "[exploding beverages] could happen a few times a year around the world." The moral of the story: If you quote MythBusters, understand what exactly they busted/proved. Lars T. (talk) 13:00, 31 August 2008 (UTC)

PS: YouTube Video

The hazards portion of the text indicates the need for citations regarding superheating. I have located two sources of verification. One is the Argonne National Laboratory:Ask A Scientist Chemistry Archive

The other on The University of New South Wales, Sydney, Australia’s website: Superheating and Microwave Ovens

Both sites are in agreement that tap will superheat. So the Mythbusters claim that tap water will not superheat is erroneous.

Muion April 1, 2009

We recently had a cup of coffee superheat in the microwave. It didn't boil until the sugar was added. Very polluted tapwater... Rob MacDonald Terrace, B.C. —Preceding unsigned comment added by 207.81.154.105 (talk) 20:49, 6 May 2009 (UTC)

I've read that you should never reheat cold coffee in a microwave. Anyone know why this is or how it affects the coffee? Or is it simply a quality issue? --Tuzapicabit (talk) 14:17, 21 May 2009 (UTC)

My understanding is that the first time water is heated, dissolved gases come out of solution, forming bubbles that nucleate boiling and prevent superheating. However, when reheating water (same goes for coffee, I assume) there's not much dissolved gas the second time around, so there might not be any bubbles to get the boiling started. Spiel496 (talk) 05:27, 8 June 2009 (UTC)

You shouldn't cite Myth Busters at all for anything- they are not really a "reliable source" - they do things mainly for show and there are known examples where they spiced things up a bit with explosives because the "experiments" turned out to not be spectacular enough. You have to clearly realize that this is *entertainment*, not really education - things may easily be said because they're more flashy, not because they're absolutely true. Citing Myth Buster is a bit like citing David Copperfield on a TV show for proof that the statue of liberty is known to occasionally disappear... Clearly it is _easier_ to superheat destilled, absolutely particle-free water, that doesn't mean it can't happen with tap-water, or even coffee, although it gets more and more unlikely the more potential nucleation sites you have. As to reheating/microwaving cold coffee... I'm sure it's done hundreds of times daily on earth... where did you read this tidbit of wisdom? Iridos (talk) 22:13, 19 February 2010 (UTC)

Social and cultural changes

The "Social and cultural changes" section is low-quality, if it's not revised soon it should be deleted. The tone is all wrong and the section is out of place compared to the rest of the entry. —Preceding unsigned comment added by 72.204.10.207 (talk) 16:01, 7 January 2009 (UTC)

This section's information is also wrong in the assumption that the concept of the TV dinner was created by the availability of the microwave oven. Stoic Squirrel (talk) 02:38, 21 January 2009 (UTC)

Not to mention the pathetic misquote from McLuhan ("The Medium is the Message") which, as any McLuhan scholar well knows, was actually "The Medium is the Massage". Of course, McLuhan always meant this to be ironic, and the error has occurred thousands, if not millions of times. But in wikipedia one would hope for more accuracy. I changed the reference, though I fear some ignorant person may change it back. [roricka 3/28/09]

This section seems to have been written as a personal essay. It contains far to many euphemisms and idioms. I deleted most of the paragraph containing the worst ones. [trumpeter675 5/25/09] —Preceding unsigned comment added by Trumpeter675 (talk • contribs) 22:17, 25 May 2009 (UTC)

I concur that this section is of low quality and of the wrong tone. It treats anecdotes as fact. I'm going to go ahead and delete the whole section. If someone can change the tone and content to say something intelligent and provide some meaningful references, then we could add it back. It's always interesting to learn about how machines change our lives, but as written, this section needs go go. Pdcook (talk) 03:56, 23 August 2009 (UTC)

Nukes?

Under "Social and cultural changes", shouldn't there be a sentence or two on how the term "nuke/nukes/nuking/nuked", in reference to using a microwave, came into the vernacular? —Preceding unsigned comment added by Skaizun (talk • contribs) 19:32, 6 June 2009 (UTC)

safety issue

"Microwaving food raises several safety issues, largely connected with leakage of microwave radiation outside the oven, as well as reducing risks, such as that of fire from high temperature heat sources."

I removed the bit about "largely connected with leakage of microwave radiation outside the oven" because we say later in the article "Tests have shown confinement of the microwaves in commercially available ovens to be so nearly universal as to make routine testing unnecessary.". It seems to me that concerns about leakage of microwave radiation are not the actual safety issues (whatever those may be) around microwaving food. That is to say, if you are worried about the safety of microwaving food, leakage of waves does not seem to me (according to what we say later in the article) to be the important thing to worry about.--Jimbo Wales (talk) 16:38, 17 August 2009 (UTC)

Exposure to microwave radiation in the frequency range used in microwaves causes some biological damage, most notably to the lens of the eye. Leaking microwaves are not safe, so it's fortunate that the seals and precautions used in modern microwave ovens are generally adequate. All methods of cooking generate hot food, and all electrical appliances present dangers of fire and electrocution; microwaves are no different than other devices in these contexts.

The idea that a microwave changes the chemistry (or resonance or essence or something) of the food cooked in it has no actual ground for belief, save poorly informed fear and urban legend.

These points are probably worth making in some way here as there are fears / problems / concerns about each of them, and WP ought not to leave them unaddressed. I'm sure some source can be found for each, but I've not the time to chase one (or all) down just now. ww (talk) 16:15, 24 August 2009 (UTC)

. I wonder if we should delete the whole section on benefits and safety features. In addition to citing no sources, the section is also anecdotal and not universally true. I've gotten nasty steam burns from cooking rice in the microwave! Can anyone find and decent source material and rewrite this section? Pdcook (talk) 15:21, 24 August 2009 (UTC)

We don't have "safety issues" sections in stove or oven either, despite the serious hazards of conventionally-heated cooking systems, especially those that use an open flame. I'd guess that far fewer people are harmed by microwave ovens than by gas-burner stoves, for example.   Will Beback  talk  17:42, 26 August 2009 (UTC)

I agree that hot food is dangerous whatever the source. The only difference with these is that there is not a large thing all of which is alarmingly hot. The cognitive dissonance between cool exterior and door and hot dangerous food is the new and possibly startling and so dangerous issue in that respect. I think worth a mention, if only that the usual warning on which we rely (automatically, more or less reflexively) is missing.

On the other hand, the assorted urban legends and myths about microwaves changing the nature of foods ("nukes it, you know") certainly do deserve mention if only in serving an encyclopedic purpose of dispelling paranoia without even the slightest grounds. This sort of unthinking, free-floating, mindless, emoting is a "reasoning" mode which seems to be gaining ground. Government death panels is another aspect of it, I think... Something in the water, maybe, ... But, in any case, WP certainly has a duty to note the lack of grounding for a belief that food is altered (other than by being heated) by microwaving. Keep weeding out the fantasy thinking, keep weeding. ww (talk)

18:03, 26 August 2009 (UTC)

Bad History

The citation for the candy bar story is awful at best, as it seems to come from some grandfather who learned to how to use the internet (literally, http://www.gallawa.com/.) I intend to rewrite this history section based off this article http://www.americanheritage.com/articles/magazine/it/2005/4/2005_4_48.shtml which seems far more credible and is from a history magazine of good repute.

There's a standard reference work for the US history of microwaves written by J. M. Osepchuk (A History of Microwave Heating Applications), and there has been a recent update article - should be available via an interlibrary loan I expect. For a VERY brief overview of the UK background, I presented a short talk presented at the annual symposium of the International Microwave Power Institute a couple of decades back, but I don't appear to have kept a copy. It was published in the annual symposium proceedings, though, and may be possible to track down. If I find/remember any more details I'll update this posting. 86.178.227.140 (talk) 09:33, 15 January 2010 (UTC) mark.sinden@tesco.net

the english - translated russian version of this article doubts also this candy bar story and if you start thinking, it does seem to be an urban legend. Or do you really think it is realistic that the microwave melts a chockolate bar in your pocket ( solid, less dipol, less ions, guessed melting point 50°C)while your body (60% water with its high dipole, many ions for the ionic heating mechanism by microwave) is fine and you dont notice anything? Getting burned probably didnt seem to be a good marketing story..( But I cannot promise that a microwave beam was pretty focussed and that exactly on the pocket only..- just doesnt seem to be realistic)--132.230.191.208 (talk) 13:07, 3 February 2010 (UTC)

picture

why is the time set to 4:20 on the oven? Twipley (talk) 03:16, 6 December 2009 (UTC)

Plastic leaching

Prompted by a question to the Reference Desk today: Could a knowledgeable editor add a paragraph to the "Hazards" section discussing the leaching of plastic into food from a plastic container? This Harvard Medical School article is a starting point, but I don't know enough about the matter. Comet Tuttle (talk) 20:49, 7 January 2010 (UTC)

No mention of Russia banning microwaves?

Why is it that there is no mention of this historical fact in the article? The article should also mention the basis under which the Russians decided to ban microwaves. Experiments were conducted and the results showed a major increase of cancer causing agents in foods cooked using microwaves. --24.201.253.252 (talk) 22:18, 9 January 2010 (UTC)

Because it is untrue. Russia did not ban microwaves and there were no experiments demonstrating cancer increase. See: Microwaves, Nazis, Cults, John F Kennedy, Anti-Semites and Christian Fundamentalists [4] Gillyweed (talk) 00:05, 10 January 2010 (UTC)

I read that link and it doesn't say anywhere that the Soviet Union did not ban microwaves. Also, the whole article is nonsense. Unfortunately, I haven't been able to find any acceptable sources that answer the question either way. Maybe someone else knows of some? 24.141.79.109 (talk) 00:05, 11 January 2010 (UTC)

I'd have thought that the article sufficiently debunks all the claims made by those who state that Russia banned microwaves to show that it is another untruth. Tell me, if I make up a statement: "That Lesotho banned microwaves in the 1950s" where will you find a statement saying "Lesotho did not ban microwaves in 1950"? Show me evidence that Russia banned microwave ovens. People can't show it because it never happened. Gillyweed (talk) 05:26, 12 January 2010 (UTC)

Sorry for late reply. That article you quoted is just a straw man. Just because a few crazy people think something is true doesn't mean sensible people don't also think it is true. A quick search of the internet shows hundreds of sources claiming that Russia banned microwaves, but none of them are good enough to quote here. I can hardly find anyone claiming the opposite, and those sources that do are also not good enough to quote here. —Preceding unsigned comment added by 24.141.79.109 (talk) 19:50, 17 January 2010 (UTC)

Hi, here is the direct link to english google-translated article about Microwave ovens of the russian wikipedia [5]and here are the important parts:

"During the Second World War in Germany, has developed the first microwave oven for use in Army field kitchens. She was named Radiomissor. During operation it turned out that food cooked in them, adversely affect the health of soldiers and of its use declined.

After the war, the work of the MP got allies. In the USSR, the MP were banned for many years, and in the U.S. have found commercial application "

I am not sure if MP is Microwave? But today it is not banned anymore:

"In the Soviet Union since the mid 80-s microwave ovens manufactured at ZIL (model "ZIL) and the Southern Engineering Works (model Mriya MV", "Dnepryanka-1" (1990, 32 liters, the power of 2,300 watts, weight 40 kg, Price 350 USD), "Dnepryanka-2"), but used them imported Japanese production of magnetrons.

As of 2009 microwave oven - one of the most common household appliances. "

--132.230.191.208 (talk) 12:57, 3 February 2010 (UTC)

Very interesting. But what is the evidence cited in the Russian WP? As we know, we can't cite the English WP as a source and so we can't cite the Russian WP as a source either! Nearly all evidence points to microwaves being developed by the US and not Germany. Gillyweed (talk) 22:19, 19 February 2010 (UTC)

I just did a Google Search on "Radiomissor." Quite fascinating. Every link copied someone elses material - copyright infringement on a grand scale. Nothing independent or verifiable. I reckon it was completely made up! Gillyweed (talk) 22:25, 19 February 2010 (UTC)

Microwave oven doors

No mention is made of the method used for preventing a microwave oven door from "leaking" where it is in close proximity to the cavity front - the "tuned quarter-wave stub" method. There is also a further enhancement to the quarter wave stub used to prevent leakage at third and fifth harmonic levels. Also, under safety, no mention is made of the internationally legally required triple door interlock system (primary, secondary and crowbar switches) to prevent accidental exposure to microwaves - the only mention is far further down in the article and very vague.

86.178.227.140 (talk) 09:13, 15 January 2010 (UTC)

Efficiency and losses incured in microwave oven cooking

Could someone proficient enough and with some time on his hands (to seek out the corresponding literature links) include this: Till then I hope it will help others to get a better picture about efficiency (my basis is education and partialy empiric results):

Here are the major losses:

• Obviously the generation of electricity itself (hence e. is relatively costly, and because it can easily be turned into pretty much everything ->demand -even into logic states i.e. your computer mobile devices, one generations from here even electron spin will matter, but naturally not in the basic flux from the generator to your home - but the theoretical point of view is interesting).

So if you were to generate your own electricity you could expect to convert around 20% into electricity in the best case, realistically it would be more like ~15% (keywords: aerobic metabolism, biophysics, motor efficiency, charging controller, inverter efficiency).

Similar figures apply for the electricity you get from the power station when averaged through global efficiencies (avg global output through avg. efficiency), and all the losses incurred in transformation, and grid maintenance (a grid is an inherently labile, extremely complex system -beyond my educational reach, but I have a glimpse of what it takes). (Yes you will argue that you live in a first world country and that the rest of the world doesn't apply to you. But I am no politician or lecturer or stand against individual viewpoints. As far as the universe is concerned there is only natural law, which given the state of physics is still only glimpsed by humankind)

MICROWAVE:

• POWER TRANSFORMATION (to several kV, see magnetron) is around 75-80% efficient, worst case safely assumed ( inverters achieve around 90-95%, unfortunately Panasonic got a patent stalling the market as you might have noticed; yet they have great difficulties with their solid state device longevity - given user reviews) keywords: see magnetic flux, magnetization, power transformation
• OVEN SIZE, a larger one will take much more power to achieve the same e. field strength (V/m) than a smaller one, whilst usually you will end up not needing that space - and there is a non linear behavior between e. field strength and power input. Do not oversize but rather underside.
• the absorption of the materials, water is around 89-90% (of energy in the local field being absorbed and turned into mol. motion, of course quantum state distribution changes as well this is what bolzman distribution is about, what the beginning of the 20th century was about, and why pH is temperature dependent and why temperature has a direct relation to the quantum states - black body radiation is what led to the discovery of a fundamental constant of nature Planck's constant). What matters here is primarily the dielectric constant.
• Absorption of water differs! If you are like me you directly put in the frozen foods, in which case absorptivity is much less. (see water molecule configuration in ice) - realistically it often isn't so bad due to high osmolarity of your organic material (i.e. fruits) and rel. amorphous structures within your bulk material, shock frozen products (prev. of ice crystal formation
  
  
  
• Material you cook in: Porcelain is a very bad choice (containing various Metals and often high dielectric constants - a boon in pizza "crisp plates" though) in fact anything unnecessarily thick, again the dielectric constant matters, vacuum has 1, apolar hydrocarbons ideally 2, water ~80+ (w. ions)! which is why dielectric heating works so well. That and our planetary chemistry dictating water to be an inherent part of the lithosphere and biosphere.
  
  

• reflection of the em-waves, and again slight absorption; plus the more dirty the inside, the more absorption and losses you incur; given that humans are lazy by default most microwaves will be unclean unless cleaning has been incorporated into the behavior of the subject
  
  
• magnetron: the material does age, like anything else (and efficiency goes down), and are around 55-60% efficient brand new;
  
  
• loss of heat: in the oven; ambient air is sucked in and warm is pushed out (my standard microwave can heat the entire kitchen)
  
  
• loss of heat: not using a cover on your dish, pan, etc...
• pressure cooking is not an option: I looked hard for this one but to no avail (there are some scammers, but then again there are amazon reviews to make you wiser).; Why: plastic gets hot and deforms, yet only materials with low dielectric constants are an option. fragile materials obviously can be ruled out. metals are ductile but as conductors out of the question. So it would more novel materials, and the market is sluggish.
  
  
• Focusing of the field where it is needed is hard: i.e. hot spot problem, and self proclaimed "3D technologies" - just try to stack food to see what I mean.
  
  
• Electric field: is inhomogenous and non linear in regard to materials and shape you have in your microwave and the power input

i.e. stacking food is an idea that hardly ever pans out (pun intended)

Still microwave ovens are great (till you actually have to produce your own energy and get a sense of a kilowatt hours in terms of moles of electrons and what can be archived with it: a Vaio P runs on 2.5-3W! - then again we greatly do care about efficiency and power usage when it comes to mobile devices) but things aren't so straightforward as often cited and re-cited, and efficiencies nowhere near what you would believe. Just try to cook the same amount of water i.e. one cup via an ohmic tungsten resistor (water cooker) with the same amount of power (certified microwave power times 1.7) (and account for some motion as does the microwave turntable).



I have no idea what the total efficiency would be, but in a thought experiment (given some background experience) I would surmise it is around 25% (water in a porcelain cup, in my over sized microwave with input power of 1700W and peak power usage of 2500W) vs. a 1700 watt water cooker (at the same ambient temperature).

BTW: Ever had sweetened oat flakes on a porcelain dish brought to the brink of almost roasting. Or oil free potato chips. Or so many other dishes that I only know how to make in a microwave, due to its unique dielectric heating properties and enormous electric field strengths if hardly anything is absorbed.Slicky (talk) 18:22, 3 February 2010 (UTC)

Brand comparisons....???

Such as the features of

• built in toaster and grill
  • http://shopping.yahoo.com/p:Sanyo%20EM-Z2100GS%20Browner%20Toasting%20Microwave%20Oven:2000790051
  • http://products.geappliances.com/ApplProducts/Dispatcher?REQUEST=SpecPage&Sku=JVM1665SNSS#FEATURES

--222.64.27.38 (talk) 02:02, 6 February 2010 (UTC)

• Steam
  • http://www.sharpusa.com/ForHome/HomeAppliances/SuperSteamOvens.aspx

--222.64.213.153 (talk) 06:06, 24 February 2010 (UTC)

• warm hold - http://www.lge.com/us/appliances/microwave-ovens/LG-over-the-range-microwave-LMVM2085ST.jsp

--222.64.27.38 (talk) 01:50, 6 February 2010 (UTC)

• Sensor cooking control and cleaning tech - http://products.geappliances.com/ApplProducts/Dispatcher?REQUEST=SpecPage&Sku=SCA2001KSS —Preceding unsigned comment added by 222.64.27.38 (talk) 02:10, 6 February 2010 (UTC)
  • Autoclave function - http://scholar.google.com/scholar?as_q=autoclave+microwave+oven&num=10&btnG=Search+Scholar&as_epq=&as_oq=&as_eq=&as_occt=title&as_sauthors=&as_publication=&as_ylo=&as_yhi=&as_sdt=1.&as_sdtp=on&as_sdts=5&hl=en--222.64.221.37 (talk) 02:34, 15 February 2010 (UTC)

how do i get the smell of an overcooked food item that was burned in the microwave? —Preceding unsigned comment added by 173.58.114.52 (talk) 02:09, 21 February 2010 (UTC)

Info about the function of radiation sanitation....

• http://www.google.com/search?hl=en&source=hp&q=radiation+sanitation+microwave&btnG=Google+Search&aq=f&aqi=&aql=&oq=&gs_rfai=

--124.78.215.31 (talk) 08:07, 20 March 2010 (UTC)

• http://scholar.google.com/scholar?as_q=microwave+radiation+sanitation&num=10&btnG=Search+Scholar&as_epq=&as_oq=&as_eq=&as_occt=title&as_sauthors=&as_publication=&as_ylo=&as_yhi=&as_sdt=1.&as_sdtp=on&as_sdts=5&hl=en
• Talk:Meal, Ready-to-Eat#Info about the topic of meal sanitization
• Talk:Meal, Ready-to-Eat#Meal radiation...meal sanitization (continued)....

--124.78.215.31 (talk) 08:11, 20 March 2010 (UTC)

harmful to food?

I would like to know whether it has been proven that microwaves are harmful to food and destroy nutrients. Are they harmful for you to eat food that has been cooked with microwaves? —Preceding unsigned comment added by 204.244.247.158 (talk) 00:40, 14 July 2008 (UTC)

The energy in microwave photons is not high enough to break most chemical bonds in such materials as food. Radiation which has that much energy is typically termed 'ionizing energy". So, at quite low frequencies (with little energy per photon), infrared radiation can only heat, not break chemical bonds. Some bonds can be broken by ultraviolet energy which is a much higher frequency. The microwave radiation in a microwave oven has much less energy than even infrared radiation, which has rather higher frequency. On the other hand, enough energy as heat can be delivered to things exposed to high intensities of either infrared or microwave radiation that the temperature can be high enough to destroy the material. Charring and all that.

So it is certainly true that microwave radiation can damage food, but it does so only with the same mechanism as a regular oven which uses infrared radiation to heat food and other things. For some foods, this will be disastrous (milk, for instance), but for others (eg, meats, some vegetables, etc) the heat is beneficial and deliberate. Heat from any source can destroy trace nutrients, but also by stopping enzymatic action within cells, preserve them. Things are not quite as simple as they might be. ww (talk) 01:02, 14 July 2008 (UTC)

There are a lot of studies showing that the microwave oven does change the chemical makeup of food. Is this not to be taken into account, or is this page just about the positive things on microwave ovens? WSNRFN (talk) 23:38, 18 August 2008 (UTC)WSNRFN

All cooking processes change the food - that's why it is no longer uncooked. If you have some reliable sources about problems with microwave ovens that aren't already mentioned, please add them here or to the page. Verbal chat 06:33, 19 August 2008 (UTC)

Yes, I will. There are plenty of studies. WSNRFN (talk) 19:58, 20 August 2008 (UTC)

Cool, but beware they need to be Reliable Sources - the "study" of watering a plant with microwaved water, that you added elsewhere, doesn't cut it. Verbal chat 20:22, 20 August 2008 (UTC)

That "study" (ahem) of a little kid (or so it is claimed) has been featured on snopes.com, also, a couple of people pointed out, that the on the left plant just a lot of leaves have been cut off and that it's unlikely that these pictures have been taken after several days, as there is no movement visible (leaves arranging towards the sun). Make very sure you don't try to incorporate things about microwaves, just because they claim detrimental effects (and so possibly align with your own views). You might look at microwave chemistry and therein microwave effect as a starting point for possible detrimental effects. While non-thermal effects don't exist in liquids, the question remains, if they can occur in solid food (although that normally contains a lot of water which can absorb the irradiation, shielding the solids). Iridos (talk) 22:13, 19 February 2010 (UTC)

I reverted an edit that cited a NYT article that was misleading in its representation of the 2003 Journal of the Science of Food and Agriculture paper; those researchers checked whether the nutrients were leaching into the water and found in fact they were not, they were being destroyed in the microwave (possibly due to higher temperatures). In the edited version that study was cited in a way that implied it found microwaving preserved nutrients in bacon, when in fact it found microwaving destroys nutrients in broccoli. Physicsjock (talk) 00:21, 19 July 2010 (UTC)

And I have reverted your edit, because you neither understood what the New York Times article actually said, but also removed another source pointing out the major mistake in the paper. Not to mention that both articles point to other papers disproving the point of the paper, which suddenly becomes the sinfgle source of argument,thanks to your editing. Lars T. (talk) 16:51, 19 July 2010 (UTC)

"Things are not quite as simple as they might be" Ain't that the truth. This is a REALLY complicated issue, and one that I don't think very many people (scientists included) give enough thought to this issue (although it could be because at the end of the day it probably doesn't matter. Its true that there is not enough energy in the microwave radiation to ionize the bonds, but the non-uniform application of the rotation to the polar molecules does allow temperature extremes in appropriately non-uniform systems that would not exist in normal radiant/conductive heating (ie normal cooking). These localized temperature extremes could (maybe) allow for reactions to occur that have activation energies beyond what you find in regular cooking methods. These would be super local though. Some of these reactions could (maybe) result in some products that aren't so good for you. The simple example of that statement is in the article. Microwaving can mess up B12, whereas it doesn't mess with spinach as much. The two cooking methods represent two profiles for the systems, which will in the end give you 2 different sets of products.

However, more than likely the reactants won't get hot enough to allow many of the dangerous reactions (in terms of final mol%) to take place, so while something naughty may get made, it doesn't matter because its below the amount that your body would even notice. —Preceding unsigned comment added by 158.35.225.229 (talk) 21:43, 17 September 2010 (UTC)

Photograph of old microwave ovens also has other things. Should be cropped or have caption corrected.

The photograph identified as "Various microwave ovens; many from the 1980s" has old microwave ovens against the far wall, but has various other things as well. There is a computer monitor in the center of the bottom. The device in the bottom-right corner appears to be a television. Either crop this to show only microwave ovens, or correct the caption.

71.109.156.114 (talk) 16:10, 3 June 2010 (UTC)

Stirrer

"The first problem is reduced by a stirrer, a type of fan that reflects microwave energy to different parts of the oven as it rotates" This is most likely false. Stirrer does nothing more but harm for the electromagnetic field, as microwave ovens interrior works as a multimode resonator. Only way to change resonance pattern inside the box would be changing the dimensions of the box.

The reason why there is such a stirrer is that the designers of cheap microwave ovens have no (or just a little) idea of what theya re doing. I personally think that no-one would hire a microwave engineer to design a microwave oven, as "almost aynone" can design this kind of cheap and trivial device. 84.251.116.191 (talk) 20:14, 27 August 2010 (UTC)

Microwaves either use a mode stirrer or rotating turntable. Either can be used to reduce standing waves and cook more evenly. How well, I'm not sure.70.176.118.196 (talk) 00:43, 17 March 2011 (UTC)

Efficiency - comparision with kettle

The Efficiency section compares the efficiency of a microwave oven with a kettle for heating a mug of water, however it has the following problems:

• When using a kettle, a heating element heats the kettle itself .... This might be true for an "old-style" kettle that one puts on a stove, but it is not true for many electric kettles. Most electric kettles I have seen have the element in the water, so that the element heats the water directly. Any heating of the kettle is by conduction from the water - which is the same as the mug in the microwave warming up because of conduction from the water.
• ... plus any extra water which is then left unused in the kettle .... This might not be the fault of the kettle, but rather the person who puts too much water in the kettle. On the other hand, the design of many kettles is such that they required a minimum amount of water to cover the element, and that amount may be more than one cup - even though you only want to boil one cup. If this is the case, the article should say so explicitly.
• ... how much energy is wasted by using other forms of cooking ... Heating water in a kettle is not "cooking".

Mitch Ames (talk) 02:39, 19 April 2010 (UTC)

• Okay, plus it is just as easy to put too much water in the MICROWAVE, making the microwave "less efficient." It's a really useless bit of writing. I'm gonna delete this paragraph about efficiency and anyone who doesn't like it can come say why!! —Preceding unsigned comment added by 24.185.249.170 (talk) 22:43, 1 February 2011 (UTC)
  • Ooooh, so if you put more water into a microwave than in a kettle, it may be less efficient? Wow, that's finally drawn me off of using a microwave. Lars T. (talk) 02:54, 7 February 2011 (UTC)

I mean. Hahaha. Who'd have suspected even the page about microwave ovens could have a pro- microwave oven slant. XD

The efficiency is Much Less compared with gas. Think of it--coal (usually) has to be burned to make heat, to make electricity, to make heat, again--and, this is just to run a a cook top, A microwave, then, loses about 25-40% due to filament heating, current to run controller,etc, and losses due to inefficiency in the RF circuit (75% efficient at best), on top of this. So, just boiling an egg with gas saves about 60% energy over a micriwave--although not as fast.70.176.118.196 (talk) 01:03, 17 March 2011 (UTC)

No citation provided for beryllia in 'Hazards' section

The article states that ceramic insulators containing beryllia are generally purple or pink colored; however, this isn't necessarily the case. Hence, an individual may stumble onto this information and figure it safe to disassemble a magnetron fitted with a white insulator. In most cases, ceramics containing beryllium oxide are actually white colored. —Preceding unsigned comment added by 202.138.9.172 (talk) 10:00, 9 August 2010 (UTC)

Merge from Microwave-related injury

I think it's rather confusing and misleading to have a separate article on Microwave-related injury, as there already is a specific hazard-section in Microwave oven (which in itself is more detailed than that whole article), as well as an article on Microwave burn (to which the rest of that little article can be merged to). Also, Microwave-related injury does not distinguish whether its scope is direct microwave damage, or indirect damage by inanimate objects placed in a microwave oven, and if it was organized in such way, it would still only be an incomplete sample of what is already found in Microwave burn and the hazard-section of Microwave oven, respectively. Mikael Häggström (talk) 10:22, 19 January 2011 (UTC)

I've done the merge now. Mikael Häggström (talk) 17:00, 29 January 2011 (UTC)

Superheating can happen in other liquids than distilled water?

I checked out the page the following quote links to: 'This can result in spontaneous boiling (nucleation) which may be violent enough to eject the boiling liquid from the container and produce severe scalding. It is commonly, but wrongly, thought that only distilled water exhibits this behaviour.[31]' And I doubt the credibilty of it. While the reasoning makes sense to a degree, it's the only page I can find which states such a thing. I wonder why micro-bubbles would not fly to the surface. Same for http://en.wikipedia.org/wiki/Superheating#Myth. — Preceding unsigned comment added by 83.83.5.118 (talk) 22:31, 24 October 2011 (UTC)

Lloyd Groff Copeman?

I demand that Lloyd Copeland's contributions be named here. He is cross-referenced on Wiki as an inventor of an early form of microwave oven. He was Linda Ronstadt's grandfather, and he is also mentioned as the inventor under that heading, The story here in Tucson is that he used to pop popcorn for lunch. One day, while working on a microwave circuit, his bag started popping. He investigated, and found a frequency of 2,2 GHz was the resonant frequency of the hydrogen molecule, and would heat anything with water in it. He built the first microwave oven--I don't know when. Whom Amana bought the patent from, I don't know. Not mentioning Copeman is like calling Sarnoff: "inventor of television", or Glen Curtiss : "Inventor of powered flight", etc.-- 70.176.118.196 (talk) 00:54, 17 March 2011 (UTC)

You demand it! Wow! It might not be a good idea because unless some reliable references can be found, he can't be included even if we do have our own Lloyd Groff Copeman article. The problem is that his article claims in the intro that Copeman was responsible for " an early form of the microwave oven" but makes no mention of that in the actual article, and gives no supporting references. Perhaps you might like to fix that article. Don't forget, his surname is Copeman, not Copeland. Moriori (talk) 02:11, 17 March 2011 (UTC)

I'd rather hear this from an Administrator, Not a User. This is why Wikipedia is not admissible in court. 70.176.118.196 (talk) 13:49, 17 March 2011 (UTC)

OK, then you hear it from me. I have removed the unsourced claim. If you have reliable sources, please provide them. Favonian (talk) 14:16, 17 March 2011 (UTC)

And by the way, it's a bad idea to remove your original comment when another user has replied to it. The dialog becomes rather difficult to follow. Favonian (talk) 14:18, 17 March 2011 (UTC)

BTW 70.176.118.196, any editor can give advice where it is needed, not just admins like me. Moriori (talk) 19:34, 17 March 2011 (UTC)

Well, I can't help you with your "requested" post, but maybe I can help us both educate ourselves. A quick search for "resonant frequency of hydrogen" showed me that there are several ways for hydrogen to be resonant... masers, mri's, others. But, none of them are at 2.2 Ghz. I'm not sure where you got that, but I do know that people tend to be confused by the concept of "resonant absorption", tending to think of it as referring to some sort of "vibrational" resonance. Is this what's happening with your understanding of the Copeman studies? Not that it matters with regard to microwave ovens, anyway, because water molecules, the main "heaters" aren't resonant at the same frequency as hydrogen, anyway. Beyond resonance... the article clearly states that any MOLECULAR RESONANCE IS NOT THE KEY TO HEATING. It is mostly simply the physical whipsawing of the various affected molecules rotating back and forth axially that manifests the heat. Heat is, as you may know, simply the average kinetic energy (mvv/2)of the molecules of a substance.

Wikis4Me (talk) 04:44, 9 August 2011 (UTC)

Personal microwave oven vs. home use microwave oven

The paragraph "The first personal microwave was introduced in 1967 by the Amana Corporation. The first microwave for home use was introduced by Tappan in 1955." might need some citation and could definitely benefit from a clarification between a "personal microwave" and a "microwave for home use"; and why are these elements not in chronological order? Tycobee (talk) 17:19, 25 June 2011 (UTC)Tycobee

A better way of distinguishing the two would be "commercial" and "domestic". — Quicksilver^{T @} 09:28, 14 December 2011 (UTC)

Is it safe to run it empty?

The "History" section of this article explains that Litton invented a microwave delivery system in the 1960's that is safe indefinitely when runnning in "no-load" conditions. I would have thought that modern manufacturers would adopt this design. Yet, in the "Metal objects" section, I'm told that running a microwave oven empty will result in destructive feedback to the magnetron tube. Which is it? I'm sure someone could clear this up easily. I'd sure appreciate it. Wikis4Me (talk) 04:06, 9 August 2011 (UTC)

There is such a mechanism! The glass surface in most microwaves will absorb just enough energy to prevent the magnetron from self-destructing. Eventually, it can get red hot, but typically, the air moving thru the microwave will result in heating of nearby surfaces, and there is almost always a thermal cut-out sensor that is sensitive to the temperature of the enclosing metal box, so the glass surface will not typically reach the red-hot temperature. Zaphraud (talk) 20:09, 19 September 2011 (UTC)

Efficiency

I note that many manufacturers seem to claim very high (approaching 90%) for some of their inverter microwaves.

The cited article in the article does not list any of the more recent ones - is anyone aware of a nice source for other than manufacturer data on testing of modern inverter microwave efficiencies? --Speedevil (talk) 22:07, 3 July 2012 (UTC)

HIST406 Critique

The Wikipedia article about the microwave oven is effective in describing the history and functions of the microwave oven in reasonable detail. The article is very readable, as it is adequately written with no major grammatical or spelling errors. It is moderately thorough, compared to other Wikipedia articles covering similar type’s inventions and technologies. The article is complete with pictures, next to certain sections, that show the development of the microwave oven over the years as well as the internal parts that make the ovens work. Aside from explaining historical background and functionality, the article also happens to be practical. It goes through safety features of microwave ovens and their effects on food and hazards. However, some of the smaller sections, like “Uses” and “Efficiency” are redundant and state either previously mentioned or assumed facts about the microwave oven. These sections could be replaced by more information about how the microwave oven actually works, which is an area that the article is currently insufficient in. There are 39 references for the article, which given the length of the article, seems like too many. However, the references at the top of the list are useful and found throughout the article. These include reliable sources like the actual J.G. Chafee microwave patent and a microwave oven regression model. The validity of the majority of references is in my opinion above average for a standard Wikipedia article. Overall, I thought this article was well written and did a good job of explaining the microwave oven. I feel like it could be shortened by eliminating some unnecessary sections, but the length of the article is a non-issue. After reading the Wikipedia article on the microwave oven, I have a more comprehensive understanding of the history of the microwave oven. — Preceding unsigned comment added by HIST406-11skenn (talk • contribs) 03:17, 5 October 2011 (UTC)

Thanks for the detailed critique. In reponse to your main point, I've removed the "uses" section since some of it was covered in the lede, and what new material remained, could be used to improve the lede (which now contains almost all the material one what microwave ovens are used for). The "efficiency" section was short and actually contained unique and important material, and was not original research (these facts are well-known and accurate) although it needs a reference. I've moved it up nearer the principles section, and added a "cite needed" tag. Personally, I don't agree this article has too many citations. It's a magnet for people to add cite tags when they run across material which contradicts common misconceptions, and stuff they thought they knew. It should be heavily referenced if it is to remain most-useful.

One reason the article has so many cites for its size is that people have been adding them for the last 2 to 4 years, but not removing the "not enough references" headers on sections. I just took 3 of those off (at least one needs to stay). SBHarris 18:09, 5 October 2011 (UTC)

Sensors used in "Smart Cook" mode?

There should be a section on what the commonly used sensor types are when it comes to the microwave's computer and what data is collects to approximate the time needed to cook/reheat a piece of food. I'm not talking about the microwaves where say you want to cook a 3 pound boneless chicken. So you hit "Chicken", then tell it whether it is boneless or not, frozen or not and the weight. That is a simple time calculation. The high end models I think do not need this info, they use sensors (moisture, heat,?) instead. — Preceding unsigned comment added by 184.76.47.120 (talk) 08:25, 29 October 2011 (UTC)

The sensors in most contemporary automatic microwave ovens are MgCr₂O₄–TiO₂ ceramic moisture sensors developed in the late 1970s/early 1980s by Tsuneharu Nitta et al. at the Materials Research Laboratory, Matsushita Electric Industrial Co., Ltd. in Osaka, Japan. You can view the first page of a paper by Nitta, published by the American Chemical Society in 1981, at http://pubs.acs.org/doi/abs/10.1021/i300004a015. The ovens that require the user to input the type and quantity of food and whether it is frozen or not, may not use such sensors at all; they're just using an algorithm or heuristic to estimate the cooking time in an "open loop" fashion. — Quicksilver^{T @} 09:26, 14 December 2011 (UTC)

Section is Extremely Biased

It seems that this section is extremely biased. The idea that some people somewhere believe that microwaving food has negative effects is lightly mentioned. The rest of the section is basically saying that microwaving food is extremely healthy and much better for you than cooking your food. Tons and tons of extremely specific examples. Why brush off the other side? In fact, most resources I found - even in a casual search - give plenty of reasons to think that microwaving is far worse than normal cooking. — Preceding unsigned comment added by TruthSeekerMN (talk • contribs) 18:41, 8 February 2012 (UTC)

Name some. What criteria did they use? It's pure temperature that kills vitamins and microwaving generally cooks at lower temperatures. The idea that some specific interaction of microwave radiation with food molecules (rather than infrared radiation that comes from a broiling element or grill) seems physically very unlikely, considering what we know of the interaction of electromagnetic radiation and molecules. But if you have evidence, let's see it. Not evidence that microwaves damage food, but that they damage it more than the equivalent amount of other types of cooking (if you're actually arguing for raw-foodism, this is not the place for it). SBHarris 19:14, 8 February 2012 (UTC)

Metals section needs correction

This section is not entirely correct and somewhat misleading. Arcing will not occur simply because a metal object has a point or sharp edge. Further, objects without points or sharp edges (a spoon is given as an example) CAN indeed cause arcing very easily. It is the presence of ANY two metal objects or surfaces in close proximity within the microwave field that causes arcing. A needle or nail by itself will not generate an arc, while a spoon will easily generate an arc if close enough to any other metal (e.g. the oven cavity wall). Of course, a single metal object can also cause arcing if it is irregularly shaped with surfaces near enough to each other (e.g. crumpled aluminum foil or the tines of a fork). I suggest that the entire section be rewritten to reflect these facts. Jfgerling (talk) 14:33, 21 April 2012 (UTC)

Microwave oven with smoke ventilation

There's no mention of microwave ovens (above the stove) with built-in extractor hoods. Gas stove, electric stove, kitchen stove, and stove doesn't even mention the modern cooking stove with the smoke vents or microwaves above the stove with the extractor hood. - M0rphzone (talk) 21:35, 16 June 2012 (UTC)

Opening sentence is terrible

"A microwave oven, often colloquially shortened to microwave, is a kitchen appliance that heats food by dielectric heating accomplished with radiation used to heat polarized molecules in food."

Dielectric heating accomplished with radiation used to heat polarized molecules in food... I can't even parse that! Especially 'radiation used to heat polarized molecules in food'. I didn't even know there was a specific kind of radiation designed to heat polarized molecules in food.

Can someone who knows the topic rewrite this opening sentence, please. 123.122.198.192 (talk) 12:48, 9 October 2012 (UTC)

There's nothing wrong with the lead paragraph. If you're talking about the technical words being used, there are already wikilinks pointing to the words/topics that you can read more about to understand. Wikipedia articles are supposed to be comprehensive and specific, so we have to use this type of language. If you can't really understand it, you can also look at the article on the Simple English Wikipedia as an additional reference to clear up any confusion or anything you don't understand. Hope this answers the issue. - M0rphzone (talk) 02:38, 3 December 2012 (UTC)

Well now you do. The specific type of electromagnetic radiation with such properties is called.... microwave radiation. Click the links, read, educate yourself. You might also check out radiation. SBHarris 02:52, 3 December 2012 (UTC)

Removed unconstructive addition

This was added into the article, but I've removed it as it is not written in the correct style and the source is not an RS. - M0rphzone (talk) 02:18, 3 December 2012 (UTC)

Dangers of cooking with microwaves

Just try to grow a plant with microwaved water and see what happens, you are the best judge. you react like a plant, just slowly.

Microwaves are agitating the molecule from inside, which then radiate inside you, that is the opposite of convection oven, which warm the food from outside.

There has been research in the soviet union "Microwaving prepared meats sufficiently to insure sanitary ingestion caused formation of d-Nitrosodienthanolamines, a well-known carcinogen. Microwaving milk and cereal grains converted some of their amino acids into carcinogens. Thawing frozen fruits converted their glucoside and galactoside containing fractions into carcinogenic substances. Extremely short exposure of raw, cooked or frozen vegetables converted their plant alkaloids into carcinogens. Carcinogenic free radicals were formed in microwaved plants, especially root vegetables." ref: http://www.powerwatch.org.uk/rf/microwaves.asp

Also in Swizerland, were the research from Hertel got him getting sued by the industry and the government... ref: http://manbir-online.com/htm3/new.45.htm

A question from a scientific ignoramous

This is going to sound odd, because I do not have the technical terms that I am able to deploy here, so bear with me. Basically, is hot food from a conventional oven molecularly different from food from a microwave? What I am trying to say is, while I am aware that microwave appliances are rigerously tested and shielded, what about the food? When one consumes microwave prepared food, is the molecular agitation still happening while it is being consumed and in the stomach? This appears to be a different kind of "heat" from conventional cooking techniques. Or at least this is my understanding. Would this factor have any potential bearing on health ? Would it in any way affect the human body? Has any studies been done on this, or is it an unexplored concept? Could there be health implications at the molecular level, and could this cause molecular damage or mutation in the human body? Or am I typing just crap? I thought of this a few years ago, and this appears to be the ideal place to air it. Any response welcome. Cheers Irondome (talk) 02:32, 25 March 2013 (UTC)

The energy in this "molecular agitation" is very rapidly converted to heat in the food when a micro wave is turned on, which is how microwaves heat food fast. So food out of a microwave only retains thermal energy, as any "molecular agitation" will rapidly dissipate. There is no different type of heat, it's a different type of heating, yes, but not some other type of heat. As for health effects, the page article actually has a section on this with some studies listed. There is no added potential for molecular damage or mutations, as microwaves are a form of non-ionizing radiation. Disclaimer: I do not professionally work with microwaves or have any specific research lab experience with them, so if someone else who does knows better, please do correct me. Reatlas (talk) 08:32, 25 March 2013 (UTC)

Thanks for the clear response. Appreciated. Irondome (talk) 19:13, 31 March 2013 (UTC)

Gratuitous addition

I would like to suggest the closing sentence be adjusted to state that persons have been exposed to microwave radiation from ovens through either deliberate action or malfunction. I don't believe it is relevant or necessary to detail the nature of these exposures, specifically "that infants have been placed inside them". — Preceding unsigned comment added by 2.96.127.107 (talk) 18:26, 11 May 2013 (UTC)

 Done Reatlas (talk) 08:11, 21 July 2013 (UTC)