Antimicrobial Activity of Vinegar on Bacterial Species Isolated from Retail and Local Channel Catfish (Ictalurus punctatus)

There is an increasing interest in applying natural antimicrobial compounds in the food industry. Consumers are increasingly avoiding the consumption of foods treated with chemicals. Natural alternatives are needed to achieve a high level of safety with respect to foodborne pathogenic microorganisms [1]. The natural sanitizers, such as organic acids, have been investigated because of their bactericidal activity [2]. Among the natural products, vinegar, also known as acetic acid, contains sanitizing properties. Vinegar is an acidic liquid that is made from the fermentation of an alcoholic beverage mainly wine [3]. The total acidity of vinegar is expressed as acetic acid which is the major organic acid in vinegar. Acetic acid is a monocarboxylic acid. It has a pungent odor and flavor. It is generally regarded as safe (GRAS) for general purpose and miscellaneous usage. According to Malicki, organic acids are considered weak acids meaning the antimicrobial effect of organic acids is mainly caused by its undissociated forms [4]. They passively diffuse through the bacteria cell wall and internalizing into neutral pH dissociating into anions and protons. Release of the protons causes the internal pH to decrease which exert inhibitory effects on the bacteria [5].