Enzyme Activity Effects on Food n Positive effects

Enzyme Activity

Effects on Food n Positive effects: n n Make food easier to eat – meat tenderizer Preserve food – change milk into cheese Improve flavor, quality, or appearance – add lactase to produce lactose-free dairy products. Negative effects: n n Enzymatic browning Spoilage B-3. 03 -- Enzyme Activity in Food 2

Make Food Easier to Eat n Meat tenderizers, enzymes that can be added: n n n during aging prior to cooking Enzymes break down tough protein fibers for a more tender product. B-3. 03 -- Enzyme Activity in Food 3

Preserve Food n n n Converting milk into cheese increases shelf-life of milk. Rennin (an enzyme) is added to coagulate milk proteins. Some enzymes are also released by bacterial cultures to create unique flavors, textures, and colors. B-3. 03 -- Enzyme Activity in Food 4

Improve flavor, quality, or appearance n n n Amylases – baked goods Invertase – artificial honey and candy Lactase – lactose- free milk Pectic enzymes – fruit juices Protease – baked goods, meat Rennin -- cheese B-3. 03 -- Enzyme Activity in Food 5

Enzymatic Browning n n Reaction of oxygen and the enzyme (phenolase) Results in desirable and undesirable color and structure changes Desirable changes – browning of raisins, figs, dates Undesirable changes -- fruit becomes discolored, mushy, bruised B-3. 03 -- Enzyme Activity in Food 6

Preventing Enzymatic Browning n Prevent oxygen from combining with the enzyme phenolase n n Cold storage slows enzyme activity. Add preservatives, such as: n n sulfites, ascorbic acid, citric acid, and/or acetic acid B-3. 03 -- Enzyme Activity in Food 7

Spoilage n Prolonged enzyme activity can cause food to spoil. n n Overripening of fruit Food processors control enzymatic activity by: n replacing oxygen to slow action of oxidases B-3. 03 -- Enzyme Activity in Food 8