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FOOD SCIENCE AND TECHNOLOGY NOTES

Questions are often asked about chemicals added to our food. This article discusses food additives, their functions, their development, and safety. J.D. Baldock, Extension Specialist, Food Technology.

MFST 900-1, Revised

FOOD ADDITIVES

Dr. Anthony Lopez
Professor of Food Technology
Department of Food Science and Technology

Food additives is one of those topics which people are either against or for. We should try to be objective when we think about or discuss this subject. Are foods of natural origin OK and "synthetic" foods harmful? We cannot answer both questions affirmatively.

Foods are a mixture of chemicals put together by nature, but we must remember that not all foods produced by nature are harmless. Some foods contain toxic substances, for example, oxalic acid in spinach and rhubarb. The presence of other toxic substances in certain species of mushrooms or berries is another example. Even the most innocent substances, salt for example, can be harmful when used to excess. Then again, we have strychnine and arsenic compounds that are extremely toxic substances, but are used for medicinal purposes in very small amounts. The criterion used as a guide today is not whether a food is or is not of natural origin, but whether the particular food has or does not have toxic characteristics in the amounts used. The burden of the proof today is on the food processing firm or on the additive manufacturer.

What are food additives? To scientists and food technologists ­ and, practically speaking, to the general public ­ a food additive is "a substance or a mixture of substances, other than a basic foodstuff, which is present in a food as a result of any aspect of production, processing, storage, or packaging". These substances are frequently divided into two classes:

On the other hand, a lawyer must view the food additive as defined in the Food Additives Amendment to the Federal Food, Drug and Cosmetic Act. The definition of a food additive from the legislative point of view is:

"Any substance the intended use of which results, or may reasonably be expected to result, directly or indirectly in its becoming a component or otherwise affecting the characteristics of any food (including any substance intended for us in producing, manufacturing, packing, processing, preparing, treating, packaging, transporting, or holding food; and including any source of radiation intended for any such use), if such substance is not generally recognized, (GRAS substances) among experts qualified by scientific training and experience to evaluate its safety, as having been adequately sown through scientific procedures to be safe in food prior to January 1, 1958, through either scientific procedures or experience based on common use in food)."

In other words, the legal definition of food additives excludes most additives in common use because they are "generally recognized as safe" (GRAS) or because they have been previously approved for use. Other substances, such as pesticides and colors, are excluded because they are covered under others sections of the law. Today, however, the GRAS list of additives is being reviewed. Thus, a food additive (to scientists and laymen) is not a food additive (to lawyers and legislators) when its use in a food has been approved according to the specifications of the Food Additives Amendment. For the purposes of this article, we will use the layman's definition.

FUNCTION OF FOOD PRESERVATIVES

Some additives are added to perform specific functions in the food product, i.e., to improve nutritive value, preserve the quality of the food, or to flavor or color the food. Other additives become part of the food product through some phase of fresh food production, processing, storage, or packaging. For example, an agricultural chemical applied to crops might be carried over into some processed foods, or a substance present in the food package might migrate into the food contained in that package. An example of the latter instance is calcium propionate used to control mold in bread or cheese by its activity in the bread wrapper. Additives such as agricultural chemicals, or substances that migrate from food packages, may be present in foods, although usually only in minute amounts. Farmers and food processors, as well as federal and state public health authorities, should all cooperate to make sure that these additives do not exceed safe limits. Food additives should be used in scientifically controlled amounts, no more than the amount necessary to perform the needed function, assuming that this amount has been found and declared safe by U.S. Food and Drug Administration.

Before we discuss uses or functions of additives, let us identify those instances when the use of additives is undesirable. The use of additives is not in the best interest of the consumers and should not be permitted:

  1. To disguise the use of faulty processing and handling techniques, such as to reduce bacterial counts or to conceal off-odors;
  2. To deceive the consumers, such as to add a color when its use has not been legally approved.
  3. When the use of the food additive results in a substantial reduction of the nutritive value of the food;
  4. When the desired effect can be obtained by good manufacturing practices which are economically feasible.

Additives perform nine distinct functions:

DEVELOPMENT OF FOOD ADDITIVES

In developing food additives, the modern chemist of food scientist often uses complex instruments, such as the spectrograph, to determine the chemical structures of certain components under investigation. However, not all research is carried on with help or multi-thousand dollar devices. In other instances, ordinary kitchen appliances and simple laboratory instruments are used, such as in determining whether a certain additive will help produce the desired consistency in a cake batter, so that the baked product will be better.

SAFETY OF ADDITIVES

At the same time an additive is being developed, its safety is tested. One way this is done is through animal feeding experiments. These studies sometimes require two years or more and may involve such experimental animals as rates, mice, or guinea pigs.

When all the studies are completed and the proposers of the new additive are convinced the additive will perform the needed function in food and that it is safe for its intended use, the research data are submitted to the U.S. Food and Drug Administration. Government scientists make a thorough examination of the research data with regard to the proposed use and safety of the additive. They approve or disapprove the use of the additive for the application requested, or they request added information.

The concept of safety involves the question of whether a substance is hazardous to the health of man or animal. Safety requires proof or reasonable certainty that no harm will result from the proposed use of the additive. It does not and cannot require proof beyond any possible doubt that no harm will result under any conceivable circumstances. Safety can be defined as the ratio of benefits to risks involved in the consumption of a food substance in a certain quantity and within a period of time. In determining safety, we must consider:

  1. the quality of the additive consumed;
  2. any substances formed in the food because of the presence of the additive;
  3. the cumulative effect of such additive in the diet of man or animals, taking into account any chemically or pharmacologically related substances in the diet; and
  4. safety factors which, in the opinion of the experts qualified by scientific training and experience to evaluate the safety of food additives, are generally recognized as appropriate.