Beat bacteria with organic acids, plant extracts

17-06-2009 | |
Beat bacteria with organic acids, plant extracts

A mixture of organic acids plant extracts turns out to be enough to greatly reduce pathogenic bacteria on chicken breast meat. Some irradiation gives a final blow to the pathogens, University of Arkansas research shows.

Food Safety Consortium researchers at the University of Arkansas System’s Division of Agriculture found that they could greatly reduce E. coli O157:H7, Listeria monocytogenes and Salmonella Typhimurium in chicken breast meat by infusing combinations of organic acids into the meat.
The experiments were also performed with extracts from green tea and grape seeds in combination with the acids.
Malic, citric and tartaric acid appeared most effective against S. Typhimurium and E. coli O157:H7, more than against L. monocytogenes. With irradiation factored in, the results were significant against all the pathogens.
Defining least amounts
“We want to determine the least amount of plant extracts that we can use and the least amount of irradiation dosage to get the best inhibitory effect,” said Navam Hettiarachchy, a UA food science professor who supervised the project.
Previous research by Hettiarachchy’s research team showed that extracts from grape seed and green tea reduced L. monocytogenes to undetectable levels when applied in combination with nisin,  bacteriocin recognized as a safe food preservative.
The researchers are also using the plant extracts to serve as antioxidants, which minimizes lipid oxidation.
Lipid oxidation is a process that causes meat quality to deteriorate by adversely affecting characteristics such as flavour, colour and texture.
Irradiation resistance
Hettiarachchy said the research team has examined the effects of irradiation on the chicken’s colour and texture and found no significant change.
Irradiation, however, has not yet been applied widely in the US as many companies have worried about potential resistance among consumers.
Hettiarachcy suggested that labels on irradiated products could have a brief explanation of irradiation to educate consumers.
“A new education component is very important and may be the key for acceptance for irradiated food products by the consumer,” Hettiarachchy said.