Science - November 11, 2011

Pomegranate juice keeps pâté fresh

An extract from the skin of the pomegranate can block the growth of bacteria in pâté, research at the Laboratory of Food Microbiology shows.

An extract from the skin of the pomegranate inhibits the growth of pathogenic bacteria in meat, such as Listeria monocytogenes, several Bacillus strains, E. coli and Staphylococcus aureus. As such, the extract can be used as a natural food preservative, report the researchers in a coming issue of the Food Control journal.
MSc student Hasmik Hayrapetyan tested the preservative effect by adding the pathogen Listeria monocytogenes and the extract to meat pâté. She then placed this in various temperatures. At 4 degrees Celsius, bacteria growth was inhibited considerably in the pâté with the extract, compared with normal pâté. The anti-microbial effect of the extract became less at higher temperatures. Furthermore, the substances in the pomegranate skin work better against Listeria than against E. coli. Nevertheless, the researchers feel that the juice is potentially useful as a natural preservative agent for meat, especially meat which is refrigerated in the production chain.
Another research project had apparently already demonstrated the anti-bacterial properties of the extract, but it did not report clearly on the effect on Listeria monocytogenes pathogens. The extract stops the growth of bacteria, but does not kill them. Nevertheless, it can be useful in the food production industry when applied with other growth inhibition treatments, says research supervisor Wilma Hazeleger. However, further research needs to be carried out to see if the extract affects the colour and taste of meat products.