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Even under the best of slaughtering and processing conditions, beef carcasses will become naturally contaminated with some bacteria from the animal's hide, hair, hooves, and the abattoir environment. This contamination is mostly composed of bacteria which are harmless, but which can ultimately cause spoilage of the beef. The shelflife of raw beef is largely determined by the numbers and types of these bacteria. Since some bacterial contamination will always be present on beef, it is desirable to reduce these numbers to decrease the rate of spoilage, increase refrigerated shelflife, and further ensure the microbiological safety of raw beef before consumption.
Any methods to reduce this bacterial contamination would greatly benefit the beef processing industry. Methods are currently used in the red meat industry to decontaminate the carcass. These include spraying of water or antimicrobial agents on the carcasses. Sprays include the use of dilute chlorine in the spray chill water or the application of dilute foodgrade acid sprays on the carcass before chilling. These acids are usually either acetic acid or lactic acid, both of which are commonly consumed food ingredients.
Any methods which would enhance the antimicrobial effect of the acid or antimicrobial agent would be a significant improvement to beef production. We have developed the idea of applying food grade acids (acetic and lactic acids) into an edible gel coating which could be sprayed onto the carcass surface before entering the chilling chamber. Gel coatings have been shown to decrease the amount of moisture loss of the carcass. Incorporating the antimicrobial agent in an edible gel on the carcass would possibly help reduce moisture loss and simultaneously reduce the amount of spoilage bacteria. Any methods which decrease the amount of spoilage bacteria will also reduce the numbers of any pathogenic bacteria which may be present such as Listeria, Salmonella, and pathogenic Escherichia coli. The purpose of this research was to test the use of alginate edible gels to coat a layer of antimicrobial agent on the carcass surface to reduce the numbers of bacteria