61C-16 |
Anti-yeast activity of heated garlic in the absence of alliinase activity |
J. W. KIM1, K. E. Park, H. J. Ko, and K. H. Kyung. (1) Food Science, Sejong University, Kunja-dong, Kwangjin-ku, Seoul, 143-747, South Korea Antimicrobial activity of garlic has been known to be generated only when fresh garlic tissue is injured and alliin is reacted on by alliinase enzyme. Heated garlic was found to be highly inhibitory to the growth of yeasts. Potency and storage stability of anti-yeast activity of heated garlic were compared with those of fresh garlic, garlic oil and related sulfur compounds found in Allium and Brassica. The anti-yeast activity of heated garlic against Zygosaccharomyces rouxii, was increased as time of heating increased up to 45 min at 121oC, and the activity did not change when garlic was heated longer up to 120 min. The ranges of MICs of heated garlic and related materials against various yeasts were as follows; heated garlic, 0.5-3.0%; fresh garlic, 0.075-0.3%; allyl isothiocyanate, 1-5 ppm; diallyl trisulfide, 3-20 ppm; dimethyl trisulfide, 10-20 ppm; garlic oil, 10-45 ppm; diallyl disulfide, 80-140 ppm; dipropyl disulfide, 80-200 ppm; diallyl monosulfide, 1000-3000 ppm. Growth inhibitory activity of heated garlic against Candida utilis ATCC 42416 was stable, and MICs did not change for 30 days at 37 oC, whereas the activities of fresh garlic and allyl isothiocyanate were extremely unstable and the MICs increased rapidly. The anti-yeast activity of heated garlic was not influenced by pH. Alliin heated in distilled water also showed anti-yeast activity similar to that of heated garlic. It was concluded that thermally generated compounds, including diallyl trisulfide, from alliin had anti-yeast activity of heated garlic. Heated garlic and its effective compounds have a good possibility of being used as natural anti-yeast preservatives in foods.
Session 61C, Food Microbiology: General I
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