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In the Food industry a large amount of enzymes is used in order to provide or obtain unique characteristics that differentiate each product. In the processes of production of bread and pasta are involved a high number of enzymes, some of them with common or similar purposes.

Enzymes in bread production

Bread is a staple food that is made primarily with cereal flour, yeast, salt and water. Enzymes can also be added, which have a key role in bread making, since they provide multiple advantages: they regulate the absorption of water, they ensure the obtaining of a thin and extensible mass prepared to be treated, and they have a great relevance in fermentation, a stage that represents one of the main targets for enzymes in the bread making process. .

Amylase

It is the enzyme most used in bread, and has three subtypes: α-amylase, β-amylase and γ-amylase, the first two being the most common. Its function is to transform the amylose and amylopectin (complex carbohydrates) of the flour into simple compounds. The yeast feeds on these simple sugars in the form of dextrins and converts them into waste products such as alcohol and carbon dioxide (CO ₂ ), which makes the dough of the future bread inflate, provides a good flavor and gives a proper color to the crust. The flour contains amylases, but does not contain the α-amylase subtype, so it is supplemented of fungal origin or in the form of malt. The α-amylase of fungal origin, which is the most used, acts on the damaged starch content, the amount of which can vary according to the type of wheat and the grinding process.

Too high doses of amylases can cause a negative effect, so there will be an excessive hydrolysis of the starch, and consequently the mass will be too plastic and will adopt the resemblance to chewing gum.

Hemicelulase

Pentosanase

These enzymes act on pentosans, a type of polysaccharide different from starch, wich it is composed of pentoses, monosaccharides of 5 carbons. Pentosans represent 3-4% of total weight in wheat flour, partially soluble and partially insoluble.

The reaction of hydrolysis of pentosans increases the absorption of water in the dough, which makes it possible to acquire new characteristics of interest:

• Stop the aging of bread, by delaying the degradation of starch.
• The absorption of water by the starch, since it is absorbed gradually over time. This allows to keep the bread for a longer time.
• The presence of pentosanas accelerates the formation of the spring and allows to acquire the desirable firmness in its structure in a shorter precooking time.

Xylanase

Xylanase is an enzyme with very specific action that degrades the polysaccharide beta-1,4-xylan to xylose. Its use favors the coagulation of the matrix of gluten, which confers a greater elasticity of the mass, allowing to increase the volume without producing the rupture of the mass or breaking. In addition, its great capacity to absorb water and, therefore, retain it, reduces the amount of water needed and lengthens the freshness of the bread.

The advantages of using this type of oxidase for bread making are:

• Ascorbic acid or chemical oxidants can be reduced or replaced.

• Improvement of the resistance of the dough.

• Makes the crust more crispy and improves the shape of the bread.

Synergistic effect of enzymes

These enzymes have a synergistic effect, because if instead of adding one or the other additions together as a complex, better performance and results are obtained. The combination of enzymes improves the properties of the dough and allows reducing the doses to be applied.

For example, the application of a high dose of xylanase would allow a certain volume increase of the mass to be achieved. This increase, however, would be conditioned by an excessive stickiness of the dough that would prevent it from handling properly. To solve it, the application of fungal alpha amylase would help us to improve the volume even more with a higher increase and we would solve the problem of stickiness, since it allows us to reduce the amount of xylanase to be applied.

Along with these data, the application of lipase would have a positive effect on the structure of the crumb. Although it would not affect the volume as significantly, the application of lipase with xylanase and fungal amylase would give more desired results in terms of volume increase and crumb structure.

Current scientific experimentation focuses on the one hand on getting new enzymes that have higher yields than the current ones, and on the other hand in finding a formulation that is more suitable for each type of bread, maximizing yield and productivity.

Inactivation by temperature

The baking is carried out at a temperature of approximately 235 ° C and lasts between 45 and 60 minutes. While the cooking progresses and the temperature increases, different phenomena occur, among which an enzymatic inactivation occurs. <Ref> Okafor, Nduka. Modern Industrial Microbiology and Biotechnology & nbsp; (in English). & Nbsp; Science Publishers, Enfield, NH, USA, & nbsp; 2007 </ ref>:

• At 45 ° C undamaged starch granules start at gelatinize and are attacked by alpha-amylases, releasing fermentable sugars.
• Between 50 and 60 ºC the yeast dies.
• At 65 ° C the beta-amylase is thermally inactivated.
• At 75 ° C the fungal amylase is inactivated.
• At 87 ° C the alpha-amylase of cereal is inactivated.
• Finally, gluten is denatured and coagulates, stabilizing the shape and measure of the bread.

Enzymes in the production of pasta

Some desirable characteristics in this type of food products can be achieved through the application of enzymes, as we have seen in the case of bread. In the pasta, the enzyme that has more relevance for the amount of tangible characteristics for the consumer that modulates is the lipase. <Ref> Whitehurst Robert J. Law Barry A .. Enzymes in Food Technology (in English). Sheffield Academic Press. CRC Press LLC, 2002. </ Ref>

Fungal Lipase

It is applied to improve the quality of the product both in conventional pasta and in Noodle. The effects are visible to the consumer since the activity of the lipase affects the color, the stability of the color, the texture when biting, the stickiness and the tolerance to cooking.

• Homogeneous appearance: The use of lipase significantly decreases the appearance of small black dots, whose quantity depends on the refinement of the flour. It also shows the reduction in the appearance of these points over time.

• Color and gloss: During the storage of the raw dough, there is a slight progressive darkening of the product. It has been proven and demonstrated that the addition of lipase reduces this gradual darkening ratio during storage. The brightness is also an important parameter especially in noodles, and improvements in brightness have been observed for both noodles with a smooth surface and those with a rough surface.

• Texture: The firmness of both pasta and noodles once cooked is one of the most important characteristics when it comes to satisfying the consumer. In noodles treated with lipase, the starch granules are smaller and the thickness of the outer layer is reduced compared to the reference.

• Cooking: It has been possible to verify that the use of fungal lipase helps us to maintain the qualities of the pasta desired for consumption even if it is overcooked for longer than adequate.