Sodium benzoate is a common food preservative. It is the sodium salt of benzoic acid and has the chemical formula C7H5NaO2. Sodium benzoate is used in a wide range of food and beverage products to prevent the growth of bacteria, yeasts, and molds, thereby increasing their shelf life.

Here are some key points about sodium benzoate:

1. Function: Sodium benzoate is an effective preservative due to its ability to inhibit the growth of microorganisms such as bacteria and fungi. It is commonly used in acidic foods and beverages, including carbonated drinks, fruit juices, pickles, salad dressings, and sauces.

2. Safety: Sodium benzoate is generally considered safe for consumption when used in the recommended amounts. It has been approved by regulatory agencies such as the U.S. Food and Drug Administration (FDA) and the European Food Safety Authority (EFSA). However, some individuals may be sensitive or have allergies to sodium benzoate, and high levels of intake may have adverse effects.

3. Acidic Conditions: Sodium benzoate is most effective in acidic environments, where it exists in its active form as benzoic acid. It inhibits the growth of microorganisms by disrupting their pH balance and preventing their metabolic processes.

4. Combining with Vitamin C: When sodium benzoate is combined with ascorbic acid (vitamin C), a reaction can occur that forms benzene, a known carcinogen. Therefore, it is recommended to avoid combining sodium benzoate with vitamin C in high-acid products.

5. Other Uses: Sodium benzoate also has applications outside the food industry. It is used as a preservative in some personal care products, such as cosmetics, shampoos, and lotions, as well as in pharmaceutical preparations.

It's worth noting that while sodium benzoate is a commonly used preservative, there is ongoing research and discussion about potential health effects and the overall safety of food additives. It's always a good idea to be aware of the ingredients in the food products you consume and consult with healthcare professionals if you have any concerns.