. Food Additives

The U.S. Food and Drug Administration (FDA) maintains a data--L base called "Everything" Added to Food in the United States (EAFUS). This database contains the names of more than 3,000 substances that are, have been, or may be legally added to foods in the United States. A number of the items listed in the EAFUS are compounds, elements, and mixtures familiar to students in a beginning chem­istry class, such as...

Preservation

Foods spoil due to two primary causes: the action of microorganisms living in the food and the natural decay processes that take place in food itself. In each of these cases, chemical changes that take place in the food are responsible for spoilage. Microorganisms such as bacteria, yeasts, and mold occur natural­ly in all foods. They grow and reproduce using the nutrients found in food to carry out their own metabolism....

PRESERVATION FROM MICROORGANISMS

As noted in chapter 1, one set of techniques for the preservation of food is designed to kill microorganisms, to reduce or stop their growth, or to prevent them from reproducing. The methods used are generally either physical or chemical. Physical methods of food preservation are designed to alter the environment in which microorganisms live, making it difficult or impossible for them to survive. Most microorganisms have...

Nicolas (francois) appert (ca. 1750-1841)

It is easy for people living in the 21st century to take food preservation for granted. Almost anywhere in the world, a person can walk into some kind of store and purchase foods that have been preserved by canning, bot­tling, freezing, drying, or some other method. In the early 1800s, however, most of the techniques that are widely available today had not yet been invented. The first such technique to have been developed...

Preservation From Natural Decay

Another form of spoilage occurs when food begins to break down by natural processes of decay. This process takes place when enzymes naturally present in foods interact with (usually) oxygen and/or water, breaking down the food's carbohydrates, lipids, proteins, and other biochemical compounds into their component parts. This type of spoilage has a number of manifestations. One such change is rancidity. When a fat or oil...