Artificial preservatives are chemical substances that are added to food, either mixed in or sprayed on the product, in order to prevent discoloration, spoilage or bacterial contamination before it can be consumed. Almost all food preservatives are placed under the category of food additives. As defined by the government under the FD&C of 1938, a food additive is a substance that, when used either directly or otherwise, affects a food’s characteristics.
Artificial Preservatives are grouped according to function: antioxidants, antimicrobial agents and chelating agents.
Antioxidants
Oxidation is a process where food reacts with the oxygen in air, aided by the presence of heat, some metals or sunlight. Foods that have been oxidized turn brownish in color or have dark spots. Oxidized foods also acquire an “off” smell. As the term suggests, antioxidants prevent oxidation that might occur in food, which ultimately leads to spoilage. Examples of antioxidants include Sulfites, Vitamin E, Vitamin C, BHA and BHT. Sulfites prevent oxidation in wines and beers. It also prevents the growth of fungi and yeast in beverages. Sulfites also preserve dried potatoes and fruits, as well as meat products. Vitamin E slows down oxidation in fresh cut vegetables and fruits. It is also used to fortify pet foods and breakfast cereals. Vitamin C prevents fresh cut fruits like apples from turning a brownish color. BHA, or Butylated hydroxyanisole, prevents oxidation in lard, baked goods, vegetable oils, butter, meats, beer and potato chips. BHT, or Butylated hydroxytoluene, prevents oxidation in oils, fats, shortenings and other related products.
Antimicrobial Agents
This group prevents bacteria from contaminating food products which then leads to food spoilage. Examples of antimicrobial agents include Benzoates, Sorbates, Nitrites and Propionates. Benzoates prevent mold, yeast and bacterial growth in beverages and liquid foods such as fruit juices, soft drinks and vinegar. Sorbates also prevent mold, yeast and bacterial growth in both foods and beverages. Nitrites prevent the growth of Clostridium botulin in smoked fish or meat products. Propionates prevent mold growth in baked food products.
Chelating Agents
Chelating agents basically prevent food from spoilage. Causes of possible spoilage where chelating agents are used include the presence of minerals such as copper and iron. These minerals can speed up the spoilage in food. Examples of this group include EDTA, Polyphosphates and Citric Acid. EDTA, or Disodium ethylenediaminetetracetic acid, slows down spoilage in food. Polyphosphates prevents browning in vegetables and fruits. This substance is mixed in with dips for fresh vegetables and fruits. Citric acid is used as an antioxidant, as well as a flavoring in food.
They also cause health problems.