Inhibition of Microorganisms by Spice Extracts and Flavouring Compounds

Abstract

Ethanolic extracts of spices and different types of flavouring compounds were tested for inhibition of some species of microorganisms in culture media. Among the tested spices, the extract from cloves was the most inhibitory to all tested microorganisms. Although other spices showed slightly inhibitory effects against gram positive bacteria, they were almost negative against gram negative bacteria. Their effects to the tested bacteria were more active in media at pH 5.0 than at pH 7.0. Phenols, alcohols, aldehydes and organic acid of the flavours used herein inhibited all tested bacteria, except Ps. aeruginosa, at concentrations of 1000 to 5000ppm in media (pH 7.0). These compounds were also inhibitory against fungi below 5000ppm; especially cinnamic aldehyde had much stronger antimould activity than potassium sorbate and inhibited the moulds at less than 10ppm.