ABSTRACT
Many chemical compounds, either present naturally, formed during processing, or legally added as ingredients, can kill microorganisms or control their growth in foods. They are, as a group, designated as antimicrobial inhibitors or preservatives. 1–3 Some of the naturally occurring preservatives can be present in sufficient amounts in foods to produce antimicrobial action, such as lysozyme in egg whites and organic acids in citrus fruits. Similarly, some of the antimicrobials can be formed in enough quantities during food processing to control undesirable microbial growth, such as lactic acid in yogurt fermentation. However, others can be naturally present or formed in small quantities and essentially do not produce antimicrobial action in foods, for example, lysozyme in milk (13 mg/100 mL) and diacetyl in some fermented dairy products. Among the many food additives, some are specifically used to preserve foods against microorganisms, such as nitrite (NO2) in cured meat to control spore germination, especially of Clostridium botulinum, whereas others are added principally to improve the functional properties of a food, such as butylhydroxyanisol (BHA) used as an antioxidant, although it has antimicrobial properties. Use of some of the preservatives started as far back as 6000 b.c. Examples include salting, which had nitrate (NO3) as a contaminant, of fish and meat; burning sulfur to generate sulfur dioxide gas (SO2) to sanitize the environment and equipment used for baking and brewing; smoking fish and meats; and adding spices, herbs, acids, and alcohol to foods (from fermentation).
