preservatives

Preservatives are substances added to foods, cosmetics, medicines, and other products to prevent spoilage and extend shelf life by inhibiting the growth of microorganisms or slowing chemical changes. They help protect consumers from foodborne illness and reduce waste by maintaining safety and quality during distribution and storage.

Preservatives are typically classified by function. Antimicrobial agents inhibit bacteria, yeasts, and molds, while antioxidants slow oxidation that causes rancidity, discoloration, and flavor loss. Some preservatives work by reducing water activity, altering pH, limiting oxygen, or improving packaging barriers.

Common antimicrobial preservatives include benzoates (sodium benzoate), sorbates (potassium sorbate), nitrites (sodium nitrite) used in cured meats, and sulfites used in wines and dried fruits. Oxidative stabilizers include ascorbic acid, tocopherols, and synthetic antioxidants such as BHA and BHT; natural extracts such as rosemary are also used. In cosmetics, parabens have been used as preservatives, though regulatory restrictions have reduced their usage in many regions.

Preservatives are widely used in foods, beverages, cosmetics, medicines, and some household products. Their use is governed by safety standards and permitted concentration limits set by authorities such as the FDA, EFSA, and WHO.

Safety considerations include possible allergic reactions and sensitivities, and, in some cases, long-term effects at high exposures. Some preservatives, such as sulfites, nitrites, and parabens, have been linked to health concerns and undergo ongoing evaluation.

Historically, preservation relied on drying, salting, fermentation, and smoking; modern preservatives emerged with advances in chemistry and food science in the 20th century, alongside refrigeration and packaging.