ABSTRACT
The growing interest in substitution of chemical food preservatives by naturalones has fostered researchs on plantessentiak oils and extracts. In this study effect of different concentrations of Zataria multiflora Boiss. Essential oil [0, 0.005, 0.015 and 0.03%] on Bacillus cereus ATCC 11778, [10[3]cfu /ml], was evaluated using sterilized samples [16 bottles containing 80 ml barley soup] and 4 different incubating temperatures [8, 10, 15 and 25°C] during 21 days. Data analysis was done using two way ANOVA. It was found that effect of different concentrations of essential oil on growth rate of Bacillus cereus ATCC 11778 was statistically significant [p<0.01]. The results suggested that Zataria multiflora Boiss. essential oil can be considered as a natural preservative in some foods