• Food preservatives include sugars and salts.olives and vegetables as preservatives/brine image by L. Shat from Fotolia.com
  
  Preservatives, both natural and artificial, are used to maintain the shelf life and characteristics of various food items. Methods of preserving foods have been used for centuries and include natural techniques such as smoking fish and meat as well as adding salts. Refrigerating and freezing food items also falls under natural ways of preserving foods. Food preservatives can also enhance the appearance of food items as well as add nutritional value.
  
  

Preservation

• Food preservatives help to lengthen the time before foods begin to spoil and mold. A common form of preservative that helps to increase the life of the food is known as an "antimicrobial agent." Common antimicrobial agents include salt and vinegar as well as sorbic acid and calcium propionate. Antimicrobial agents are commonly used in food items including baked goods, butter and margarine, dressings for salads, cheeses, and foods that are pickled. Antioxidants can also be used as a way of preserving food items from spoilage. Antioxidants help to protect foods containing fat from going bad or being exposed to oxygen. Vitamins A and C are common antioxidants used as food preservatives.
  
  

Coloring

• Food preservatives can also help to improve the appearance of food items. Artificial coloring can enhance the coloring of the food item to make it more appealing to the consumer. Bleaching agents, including peroxide, add a vibrant white color to food items. Bleaching agents are commonly used to color foods such as cheeses and flour to help vivify the natural colors of the food items.
  
  

Enhance Flavor

• Artificial flavorings are added to food items to give them a specific taste or to add sweetness. Common food preservative flavoring agents include sugar, vanilla and salt. Food preservative flavoring agents can help to enhance or boost other flavors in the food item.
  
  

Add Nutrients

• Food preservatives can use the processes of both fortification and enrichment to help add nutrition to food items. Enriching food items deals with adding in minerals and vitamins to compensate for the nutrition that was lost in the production of the food. Fortifying food items with food preservatives involves adding minerals and vitamins to increase the nutritional value of the food. Common forms of fortifying elements include Vitamin D, which is commonly added to milk, and iron.
  
  

Protection

• Both natural and artificial methods of preserving foods help to protect the consumer against illnesses that can occur from eating spoiled or contaminated foods. Food preservatives help to protect against common food-related ailments such as food poisoning.