1. Maintain product consistency
Substances called emulsifiers provide a consistent texture and prevent products from separating. Stabilizers and thickeners provide an even texture. Anticaking agents allow substances to flow freely.
2. Improve or preserve the nutrient value
Many foods and drinks are fortified and enriched to improve the nutritional status of the United States population. For example, vitamins and minerals are added to many foods including flour, cereal, margarine, and milk. This helps to make up for vitamins or minerals that may be low or completely lacking in a person's diet. All products that contain added nutrients must be labeled.
3. Maintain the wholesomeness of foods
Contamination from bacteria can allow foodborne illnesses to occur. Preservatives reduce the spoilage that air, fungi, bacteria, or yeast can cause. Certain preservatives help preserve the flavor in baked goods by preventing the fats and oils from going bad. They also keep fresh fruits from turning brown when exposed to the air.
4. Control the acidity and alkalinity and provide leavening
Specific additives help change the acid-base balance of foods to obtain a desired taste, color, or flavor. Leavening agents that release acids when they are heated react with baking soda to help biscuits, cakes, and other baked goods rise.
5. Provide color and enhance flavor
Certain colors improve the appearance of foods. There are many spices and natural and synthetic flavors that bring out the best in the flavor of food.