What exactly do food preservatives do?

Question

What exactly do food preservatives do?

Answer 1

A preservative is a natural or synthetic chemical that is added to products such as foods, pharmaceuticals, paints, biological samples, wood, etc. to prevent decomposition by microbial growth or by undesirable chemical changes.

Preservatives in foods

Preservative food additives can be used alone or in conjunction with other methods of food preservation. Preservatives may be anti-microbial preservatives, which inhibit the growth of bacteria and fungi, or antioxidants such as oxygen absorbers, which inhibit the oxidation of food constituents. Common anti-microbial preservatives include calcium propionate, sodium nitrate, sodium nitrite, sulfites (sulfur dioxide, sodium bisulfite, potassium hydrogen sulfite, etc.) and disodium EDTA. Antioxidants include BHA and BHT. Other preservatives include formaldehyde (usually in solution), glutaraldehyde (kills insects), ethanol and methylchloroisothiazolinone. The benefits and safety of many artificial food additives (including preservatives) are the subject of debate among academics and regulators specializing in food science and toxicology.

Natural food preservation

Natural substances such as salt, sugar, vinegar, and diatomaceous earth are also used as traditional preservatives. Certain processes such as freezing, pickling, smoking and salting can also be used to preserve food. Another group of preservatives targets enzymes in fruits and vegetables that continue to metabolize after they are cut. For instance, citric and ascorbic acids from lemon or other citrus juice can inhibit the action of the enzyme phenolase which turns surfaces of cut apples and potatoes brown. Caution must be taken, however, since FDA standards do not currently require fruit and vegetable product labels to accurately reflect the type of preservative used in the products. Further, there is no current regulation requiring the inclusion of preservative chemical in labels at all; some potentially hazardous. While sometimes labeled as "natural" preservatives, most fruit and vegetable products contain carcinogenic chemicals.

Answer 2

make the food have a longer shelf life.. not go bad so quick

Answer 3

help to slow down the spoiling of food by microscopic organisms.

Answer 4

They preserve the food, so it will last longer and to prevent spoilage.

Answer 5

They preserve the food so it lasts longer!!

Answer 6

apparently preservatives ensure your packaged/canned foods last longer on shelves.