Food Processing And Preservation

11 Pages 2629 Words

s. But when the plants and animals are killed, the organisms yeast, mold, and bacteria begin to multiply, causing the food to lose flavor and change in color and texture. Just as important, food loses the nutrients that are necessary to build and replenish human bodies. All these changes in the food are what people refer to as food spoilage. To keep the food from spoiling, usually in only a few days, it is preserved. Many kinds of agents are potentially destructive to the healthful characteristics of fresh foods. Microorganisms, such as bacteria and fungi, rap!
idly spoil food. Enzymes which are present in all raw food, promote degradation and chemical changes affecting especially texture and flavor. Atmospheric oxygen may react with food constituents, causing rancidity or color changes. Equally as harmful are infestations by insects and rodents, which account for tremendous losses in food stocks. There is no single method of food preservation that provides protection against all hazards for an unlimited period of time. Canned food stored in Antarctica near the South Pole, for example, remained edible after 50 years of storage, but such long-term preservation cannot be duplicated in the hot climate of the Tropics.

Raw fruits and vegetables and uncooked meat are preserved by cold storage or refrigeration. The cold temperature inside the cold-storage compartment or refrigerator slows down the microorganisms and delays deterioration. But cold storage and refrigeration will preserve raw foods for a few weeks at most. If foods are to be preserved for longer periods, they must undergo special treatments such as freezing or heating. The science of preserving foods for more than a few days is called food processing.

Human beings have always taken some measures to preserve food. Ancient people learned to leave meat and fruits and vegetables in the sun and wind to remove moisture. Since microorganisms need water to grow, drying the food sl...