effect of thyme and ajowan essential oils on preventing growth of aspergillus parasiticus in pistachio

the effect of thyme and ajowan essential oils (200µg/l and 300µg/l respectivilly ) on growth of aflatoxin-producing strain of aspergillus parasiticus on 2 stages of pistachio (green and with dry peel ) was studied . also organoleptic tests for evaluating odor and flavor residual of essential oils on pistachio were also performed tested . the collected data were statistically analyzed. the results showed that thyme essential oils at 200 µg/l had stronger effect than ajowan essential oils at 300 µg/l in terms of control the growth of aspergillus parasiticus inspite of more thymol content of ajowan which might be as a resalts of synergistic effect between thymol and other phenolic compounds such as carvacrol in thyme. evaluation of organoleptic by 13 panelists showed that the sample which was treated by ajowan oil scored as more acceptable than the others. it was concluded that both thyme ajowan essential oils are promising natural fungistatical agents and can be used instead of currently used synthetic fungicides. keyword : essential oil , thyme , ajowan , aspergillus parasiticus , pistachio