Sodium benzoate

Basic Properties

1. Appearance and Characteristics: It has no odor or a slight anisic smell, and tastes slightly sweet with a bitter aftertaste.

2. Solubility: It is easily soluble in water, and the aqueous solution is weakly alkaline.

3. Acid-base dependence: It belongs to an acidic preservative and has the best antibacterial effect in acidic environments (with the optimal pH range of 2.5–4.0). It has almost no bactericidal or bacteriostatic effect in alkaline media.

Safety and Metabolism

1. Metabolism in the Body: After entering the body, sodium benzoate combines with glycine in the liver to form malic acid and is ultimately excreted from the body through urine, without accumulation in the body.

2. Safety: Use within the permitted limits in various countries is safe. However, if sodium benzoate is stored with vitamin C (ascorbic acid) under specific conditions for a long time, theoretically, a trace reaction may produce a small amount of benzene (a carcinogen), so modern formulations usually strictly monitor or avoid the unreasonable high concentration combination of the two.