Enzyme Use by the Food Industry
Many foods would not be on the market if it were not for certain enzymes. Foods that can be manufactured with the aid of enzymes include wines, cheeses, corn syrups, yogurt, cottage cheese, baked goods, sausages, juices, egg white replacers. the artificial sweetener.
- Aspartame, and vanous oriental foods relying on molds. Some examples include:
- Rennin, also known as chyrnosin, aids in cheese production by converting milk to a curd.
- Meats can he tenderized with the enzymes of papain, bromelain, and/or ficin.
- Phenol oxidase imparts the characteristic dark hue to tea, cocoa, coffee, and raisins.
- Glucose oxidase has been used for decades in the desugaring of eggs, flour, and potatoes, and in the preparation of salad dressings.
- Manufacturers of baked products use enzymes to retard staling, improve flour and dough quality, bleach flour, and enhance crust color.
- Enzymes can also be used in improving the filtration of beer.
Fruit juice processors use enzymes to increase juice yields, enhance juice clarity, improve filtration, reduce bitterness, and speed fruit dehydration. The enzymes most commonly used by fruit juice processors are pectinase, cellulase, hemicellulase, amylase, and arabinase. The bitter compounds in grapefruit juice — naringin and limonin — can be hydrolyzed with naringinase and limonase respectively.
Sometimes the food industry is – more interested in inhibiting the action of enzymes. This is the case for lipoxygenase activity in milk. which produces off-flavors. The vulnerability of enzymes to high temperatures makes it easy to destroy enzymes that cause the spoilage of fruits and vegetables. Briefly submerging foods (usually vegetables) in boiling water denatures the enzymes that contribute to deterioration. Pasteurization of milk, which is intended to kill harmful bacteria, also halts enzyme activity.
Another major use of enzymes by the food industry is in quality testing of a variety of food products. A test for ensuring that adequate pasteurization temperatures have been reached is to measure the activity of the phosphatase enzyme that naturally exists in milk. Lack of phosphatase activity indicates that sufficient heat was applied to destroy harmful microorganisms. Fish quality can be measured by using xanthine oxidase, which acts on hvpoxanthine, a compound that increases as the fish spoils. A strip of absorbent paper soaked partially in xanthine oxidase can be used aboard ships, dockside, or in a food processing plant. The strip of paper is moistened in fish extracts and then observed for color intensity, which is correlated to freshness. Enzymes can also now be used to detect bacterial contamination in meat, poultry, fish, and dairy products.