Sodium benzoate is a common type of food preservative and is the sodium salt of benzoic acid. Food manufacturers make sodium benzoate by synthesizing the compounds, sodium hydroxide and benzoic acid, together. In addition to its use as a food preservative, sodium benzoate has other roles in food production as well. There are some side effects associated with excess sodium benzoate consumption in foods, so talk with your doctor about it to make sure you are not ingesting harmful doses of preservatives.
Mechanism of Food Preservation
Sodium benzoate preserves food by having anti-fungal properties, protecting foods from invasion by fungi that cause food to spoil and potentially make you sick. Sodium benzoate works by entering the individual cells in the food and balancing its pH level, increasing the overall acidity of the food. By lowering the intracellular pH of certain foods, sodium benzoate creates an environment in which fungi cannot grow and spread.
According to the International Program on Chemical Safety, sodium benzoate is heavily used by the soft drink industry due to the demand of high-fructose corn syrup in carbonated drinks. Sodium benzoate increases the acidity of soft drinks, which also increases the intensity of flavor you get from the high-fructose corn syrup. On the back of a soda can, you can find sodium benzoate in the ingredients list as E211, which is the number assigned to it as a food additive.
Sodium benzoate is primarily added to acidic foods to enhance their flavor. It can be found in foods such as pickles, sauces, jams and fruit juices. Foods that contain vinegar, such as salad dressings, typically contain very high levels of sodium benzoate. Benzene, a precursor to sodium benzoate, can be found in very small amounts naturally in some fruits, vegetables, meats, dairy products and even drinking water.
Sodium benzoate, when combined with vitamin C, forms benzene. Benzene is a carcinogen and is known to contribute to the formation of many different types of cancer. However, the Food and Drug Administration states that food products that contain both vitamin C and sodium benzoate express benzene levels that are below the dangerous limit. Talk to your doctor about sodium benzoate, especially if you consume a lot of foods and drinks that contain high levels of this food additive.
- "Nutrition for Health, Fitness, and Sport"; Melvin H. Williams; 2002
- "Biochemistry Journal"; Studies on the Mechanism of the Antifungal Action of Benzoate; H.A. Krebs, et al.; September 1983
- International Program on Chemical Safety: Benzoic Acid and Sodium Benzoate
- NVaging.net: Aluminum and Benzene in Foods
- AibOnline: Production of Benzene from Ascorbic Acid and Sodium Benzoate
- FDA; Data on Benzene in Soft Drinks and Other Beverages; May 2009