Sodium Sulfite a Food Additive

Food additives are chemicals added to food during their preparations to obtain an effect. This effect can range from addition of coloration, flavor to the food, or it can cause food to have a prolonged shelf life, as in the case of preservatives.

Usually food additives can be divided into 2 types, direct additives and indirect food additives. Direct food additives are those that are added to the food intentionally to food e.g. flavoring agents, artificial colors etc. An exact quantity of the additive is measured and added to the product and exposure to the public of the additive can be measured. Indirect food additives are those additives that are not intentionally added to food, but do become components of it as is the case of packaging materials, plastics wraps paper packs, laminates etc. The estimation of the exact quantity of compounds which have indirectly been released into the foods and are now exposed to humans for consumption can not be straightforwardly calculated. (Estimating exposure to direct food additives)

One such material which is added to foods as an additive is sodium sulfite. It is manufactured on an industrial scale by passing sulfur dioxide through caustic soda, which causes in the end sodium sulfite crystals to form. This is slightly unstable compound and releases sulfur dioxide gas slowly into the atmosphere. This ability provides it with the properties of an Antimicrobial Agent, Antioxidant and a Preservative. Different preparations are made of this product, food grade sodium sulfite and the non food grade preparation which is used in the paper industry as a bleaching agent and the photo industry for developing solution preparations. (Sodium sulfite grades)

Before any food can be allowed to be used as an additive it has to be proven as safe by the Food and Drug Agency (FDA) for its use. Concerning Sodium Sulfite, the FDA states that it can be used as a preservative as it is generally considered as safe for the desired purpose, but it should be prepared with good manufacturing practices and used only as is required in quantity and no more. It has no quantitative limitation put on it by the FDA, if it is used as a preservative. If the purpose use is as a boiler additive, then the FDA prevents its use on meats fruits and vegetables, which have to be presented as raw or fresh any food considered to be a vitamin B1 source. (Food Additive Status List)

Food additives are taken for granted in many ways. The reason fruits are available all year round, the reason baked goods stay fresh for so long, and we owe it all to additives and preservatives. If we were to stop using all preservatives, most of the snacks we consume would cease to exist and availability of food products would become limited to certain areas and for only a small amount of period in a year only. Additives are for five main reasons.

• To maintain consistency as is done with artificial foods.

• To prevent spoilage. Use of preservatives prevents food from ruining early. Fungi, bread mould are prevented from growing as preservatives create an inhospitable environment for them. Antioxidants additives keep fruits fresh and prevent bad taste from developing in baked goods.

• To maintain or to fortify the nutritional value. This is usually done with breads cereals which are usually fortified with iron, or with milk which is fortified with calcium and vitamins.

• To enhance the flavor and color. This is done with chips snacks or flavored drinks.

• To control the pH of the food. This is necessary as in preparation of baked foods like biscuits or cakes. (Food additives)

Foods additives are very much integrated into our lives without us even know knowing about it. They help in the proper preparation of food, its availability, and ability to stay fresh for long. They act as anti microbial agents, anti oxidants flavoring agents, bleaching agents, preservatives, fortifying agents and stabilizing agents. Although their availability has provided us with immense opportunities but it all comes at a price as well. Most of the additives are chemicals. The FDA approves additives by labeling them either safe for general consumption, or substances allowed limited use and substances which require further approval from FDA before use. (Food Additive Status List). This is done as certain additives are hazardous to health in large quantities. Sulfites are shown to be mutagenic towards bacteria although no proof of these effects has been reported in humans the risk still persists. It is reported to increase the incidence of acute asthma and in some people cause gastro intestinal symptoms if present in food products greater than trace amounts. Other additives have the ability to cause chronic ill effects to excessive consumption of the food for a long period of time.

Amongst its many uses, sodium bisulfite is primarily used in almost all wine making industry to prevent oxidation of grape juice to vinegar. Secondarily, it is used as an anti microbial agent and as a food color preservative in the canned food industry by preventing oxidation and browning.

In the United States, the Environmental Protection Agency (EPA) uses 2 statutes to regulate the licensing and usage of pesticides and fungicides etc. These are the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) or the Federal Food, Drug and Cosmetics Act (FFDCA). The FFDCA sets the rules and regulations concerning tolerance limits of pesticides, byproducts of fungicides and of food additives. The EPA, when registering a pesticide, approves these products after a risk versus benefit analysis. However, there is clause in the FFDCA which bans use of food additives which has even a small risk ill effect in humans; therefore it sets a zero risk benchmark for the industry to meet. This is called the Delaney’s clause. This is problematic for the EPA since it creates 2 different standards for the industry to meet. The FIFRA analyses the risk versus benefit aspect whereas the FFDCA which has the Delaney’s clause has a zero risk standard. So some a food additives or pesticides meet the FIFRA standard do not meet the FFDCA standard. This has created obstructions in the smooth functioning of the EPA as far as approval and re registration of pesticides and food additives is concerned. Finally the National Academy of Sciences (NAS) a Non Governmental organization has looked into this matter and made the following recommendations. It states that there should be one universal standard for all approvals, processed or raw food, old or new pesticide. It also states that rather than having a zero risk policy, the EPA should adopt a negligible risk policy which should be acceptable both, the FIFRA as well as the FFDCA. (Delaney’s paradox)

References/ Bibliography

DiNovi, Michael J. and Kuznesof, Paul M. “Estimating Exposure to direct food additives and chemical contaminants in the diet.”

U.S. Food & Drug Administration Center for Food Safety & Applied Nutrition Office of Pre market Approval (Aug 2006) http://www.cfsan.fda.gov/%7Edms/opa-appa.html

“Food Additives” FDA/IFIC Brochure. Jan.1992. U. S. Food and Drug Administration http://vm.cfsan.fda.gov/~lrd/foodaddi.txt

“Food Additive Status List” CFSAN/Office of Food Additive Safety. 2006. U.S, Food and Drug Administration. 21 Dec 2006 http://www.cfsan.fda.gov/~dms/opa-appa.html

“Sodium sulfite grades.” Sodium and Potassium sulfites. 2006. BASF The chemical company. 19 Dec 2006. http://www.inorganics.basf.com/

“The Delaney Paradox and Negligible Risk Fact Sheet.” Pesticide Management Education Program. Jan.1991. Cornell University Cooperative Extension

http://pmep.cce.cornell.edu/issues/delaney-negrisk.html