Sodium Benzoate

Sodium benzoate is the sodium salt of benzoic acid, with the chemical formula C7H5NaO2. It is a white, crystalline powder that is odorless or has a slight characteristic odor. Here are some key points about sodium benzoate:

1. Chemical Structure: Sodium benzoate consists of a benzene ring (C6H5) with a carboxyl group (COOH) attached, and the hydrogen of the carboxyl group is replaced by a sodium ion (Na+). Its chemical formula is represented as NaC7H5O2.
2. Production: Sodium benzoate is typically produced by the neutralization of benzoic acid with sodium hydroxide or sodium bicarbonate. It can also be synthesized through the reaction of benzene with chlorine to form chlorobenzene, followed by hydrolysis and oxidation to produce benzoic acid, which is then converted to sodium benzoate.
3. Properties:
   • Solubility: Sodium benzoate is highly soluble in water, with a solubility of approximately 62 grams per 100 milliliters at room temperature. It is also soluble in alcohol and glycerol but insoluble in most organic solvents.
   • pH: Sodium benzoate is stable over a wide pH range, typically between 2 and 8. It is commonly used as a preservative in acidic foods and beverages.
   • Antimicrobial Properties: Sodium benzoate exhibits antimicrobial properties against bacteria, yeast, and fungi. It inhibits the growth and proliferation of microorganisms by disrupting their metabolic processes and cellular functions.
4. Uses:
   • Food Preservative: Sodium benzoate is widely used as a preservative in various food and beverage products to prevent spoilage and microbial contamination. It is particularly effective in acidic foods and beverages, such as soft drinks, fruit juices, pickles, salad dressings, and condiments.
   • Cosmetics and Personal Care Products: Sodium benzoate is also used as a preservative in cosmetics, skincare products, and personal care items, such as shampoos, lotions, creams, and oral care products. It helps extend the shelf life of these products and prevents the growth of bacteria and fungi.
   • Medications: Sodium benzoate is sometimes used as a preservative in pharmaceutical formulations, particularly liquid medications, syrups, and topical preparations. It helps maintain the stability and efficacy of active ingredients and prevents microbial contamination.
5. Safety Considerations: Sodium benzoate is generally recognized as safe (GRAS) for use in food and pharmaceutical products by regulatory agencies, including the U.S. Food and Drug Administration (FDA) and the European Food Safety Authority (EFSA). However, some individuals may be sensitive to sodium benzoate, and high concentrations of benzoate in food and beverages have been associated with allergic reactions and adverse effects in sensitive individuals.
6. Regulatory Approval: Sodium benzoate is approved for use as a food additive and preservative in many countries worldwide. It is assigned the E number E211 in the European Union and is listed as a Generally Recognized as Safe (GRAS) substance by the FDA in the United States.