Another story concerning our foe E.coli 0157:H7 for you. New research from Japan to be published in the March 2014 edition of Food Control describes the use of polylysine and carbon dioxide to reduce the incidence of E.coli 0157:H7 and Salmonella contamination of beef.
Polylysine is a polymer of the essential amino acid Lysine that is produced naturally by the bacteria Streptomyces. The antimicrobial properties of polylysine were first described in the late 70’s by Japanese researchers and is commonly used as a food preservation in Japan, Korea and more recently, the US. Food is routinely packaged in carbon dioxide, nitrogen or mixes of these gases to inhibit microbial growth and extend shelf life by reducing oxidation.
The research was prompted by an outbreak of E.coli 0157:H7 from ingestion of raw beer in Japan in 2011 that lead to 5 deaths and 181 cases of illness.
The researchers demonstrated that polylysine significantly reduced the number of E.coli and Salmonella on the surface of raw meat. A carbon dioxide environment did not significantly reduce the level of the bacteria when stored at the recommended 4°C but did have an significant effect when the meat was stored at 10°C.