Submitted to: Journal of Food Protection
Publication Type: Peer reviewed journal
Publication Acceptance Date: 2/21/2006
Publication Date: 7/14/2006
Citation: Hinton Jr, A., Ingram, K.D. 2006. Antimicrobial activity of potassium hydroxide and lauric acid towards microorganisms associated with poutlry processing. Journal of Food Protection. 69:1611-1615. Interpretive Summary: Experiments were conducted to examine the ability of solutions of potassium hydroxide and mixtures of potassium hydroxide and lauric acid to kill microorganisms found in poultry processing perations. First, bacteria found on processed chicken meat were suspended in peptone water, solutions of potassium hydroxide, or mixtures of potassium hydroxide and lauric acid. The number of bacteria that survived these treatments was then determined. Results of these experiments showed that although potassium hydroxide killed some of the bacteria in the suspensions, more bacteria were killed when they were suspended in mixtures of potassium hydroxide and lauric acid alone. Additional experiments were conducted to determine if the number of bacteria and yeast on chicken skin could be decreased by washing the skin in solutions of potassium hydroxide or potassium hydroxide and lauric acid. Results from these experiments showed that washing the skin in solutions of potassium hydroxide killed some of the bacteria and yeast on the skin, but washing the skin in solutions of potassium hydroxide and lauric acid kill more of these microorganisms. Findings from these experiments that mixtures of potassium hydroxide and lauric acid may serve as an alternative sanitizer for killing bacteria and yeast found on chicken meat.
Technical Abstract: Antimicrobial activity of solutions of potassium hydroxide (KOH) and mixtures of KOH and lauric acid (KOH-lauric acid) towards microorganisms associated with poultry processing was determined. In vitro tests were performed by suspending bacteria in peptone water, solutions of KOH, or mixtures of KOH and lauric acid, and then enumerating viable organisms recovered. Results of studies indicated that although KOH reduced bacterial populations, the synergistic activity of KOH and lauric acid was greater than bactericidal activity of KOH alone. In further studies, the effect of KOH and KOH-lauric acid solutions on populations of total bacteria, E. coli, campylobacter, enterococci, lactic acid bacteria, pseudomonads, staphylococci, and yeast on poultry skin was examined by washing skin from broiler carcasses in distilled water, KOH, or KOH and lauric acid and then enumerating microorganisms in skin rinsates. Results indicated that washing the skin in solutions of KOH reduced the population of microorganisms recovered, but fewer microorganisms were recovered from skin washed in KOH-lauric acid solutions. Lactic acid bacteria and staphylococci possessed the highest level of resistance to the bactericidal activity of KOH-lauric acid. Findings indicate that KOH and KOH-lauric acid possess antimicrobial activity that can reduce populations of microorganisms associated with poultry in vitro or on poultry skin. The antimicrobial activity of mixtures of these two compounds may serve as an alternative sanitizer for reducing the level of microbial contamination associated with poultry processing.