Foods enzyme applications

Enzymes not only produce characteristic and desirable flavor (79) but also cause flavor deterioration (80,81) (see Enzyme Applications, Industrial). The latter enzyme types must be inactivated in order to stabilize and preserve a food. Freezing depresses enzymatic action. A more complete elimination of enzymatic action is accompHshed by pasteurization. 

In the early years of the chemical industry, use of biological agents centered on fermentation (qv) techniques for the production of food products, eg, vinegar (qv), cheeses (see Milk and milk products), beer (qv), and of simple organic compounds such as acetone (qv), ethanol (qv), and the butyl alcohols (qv). By the middle of the twentieth century, most simple organic chemicals were produced synthetically. Fermentation was used for food products and for more complex substances such as pharmaceuticals (qv) (see also Antibiotics). Moreover, supports were developed to immobilize enzymes for use in industrial processes such as the hydrolysis of starch (qv) (see Enzyme applications). 

Novozymes is a market leader in enzyme solutions. Their manufacturing capabilities are based on an advanced biotech platform, for identifying new enzyme applications. Novozymes produces and sells more than 500 enzyme products covering more than 20 different industries in the food, feed and technical sectors, in 120 countries. With more than 75 types of enzymes and almost 600 different products, Novozymes has the world largest enzymes portfolio. 

The following factors appear to control the emulsification properties of milk proteins in food product applications 1) the physico-chemical state of the proteins as influenced by pH, Ca and other polyvalent ions, denaturation, aggregation, enzyme modification, and conditions used to produce the emulsion 2) composition and processing conditions with respect to lipid-protein ratio, chemical emulsifiers, physical state of the fat phase, ionic activities, pH, and viscosity of the dispersion phase surrounding the fat globules and 3) the sequence and process for incorporating the respective components of the emulsion and for forming the emulsion. 

Table 5.3 Examples of enzyme applications in the food and detergent sectors [35],...

Swaisgood, H.E. 1991. Immobilized enzymes applications to bioprocessing of food In Food Enzymology (P.F. Fox ed.), Vol. 2, pp. 309-341. Elsevier Applied Science, New York. 

Proposed or Emerging Enzyme Applications. Several new enzymes and/or new applications are known today but are not commercialized or widely used. Induction time, changes in economics, food regulations, or processing practices could result in overnight acceptance of what now seem to be unfamiliar, marginal, or uneconomic applications. Textured soy was not accepted until the price of meat dramatically increased. Table IV lists examples of proposed enzymes and new or limited applications. However, it contains only a fraction of the possibilities. 

There is a millennium of history of enzyme application in the improvement of food. Cheese production, the production of seasoning sauces, fermentation of raw sausages, tea and tabacco fermentation are only a few examples. In all these cases enzymes have been applied as a part of the living enzyme containing micro-organisms. Today many of those enzymes are characterized and available as pure substances in high concentration. They facilitate a precise operation and safe control of the manufacturing process. 

There are several bulk industrial enzymes that are applied on a large scale, as outlined by Ward. Carbo-hydrases are used to process starches. Cellulase can convert cellulose, the largest component of biomass, into sugars that can be further converted into fuel ethanol via fermentation. Proteases have several industrial applications, particularly in the food processing industry. Lipases and lactases are used in several food processing applications as well. 

The caloric value of a food is applicable in humans only if our cells have enzymes that can oxidize that fuel by transferring electrons from the fuel to NAD+, NADP+, or FAD. When we burn wood in a fireplace, electrons are transferred from cellulose and other carbohydrates to O2, releasing energy as heat. However, wood has no caloric content for humans we cannot digest it and convert cellulose to a form that can be oxidized by our enzymes. Cholesterol, although a lipid, also has no caloric value for us because we cannot oxidize the carbons in its complex ring structure in reactions that generate NADH, FAD(2H), or NADPH. 

The problems of choosing one of the several commercial enzymes for a specific food system application are (1) wide ranges in enzyme activities assayed by different methods, (2) batch to batch variability, (3) different pH and temperature profiles depending on the source, (4) activators or inhibitors necessary for the reaction, and (5) compatibility of combining two or more enzymes. ... 

Swaisgood, H.E., Immobilized enzymes Applications to bioprocessing of food, in Food Enzymology, Fox, P.F., Ed., Elsevier Science Publishers LTD, Essex, U.K., 1991. 

---