Germination Rate and Microbial Safety during Cultivation of Disinfected Seeds

새싹 종자 소독 여부에 따른 발아율과 재배기간별 미생물 오염도

  • Park, Eun-Jung (Department of Food Science and Nutrition, Kyungpook National University) ;
  • Kwon, Joong-Ho (Department of Food Science and Technology, Kyungpook National University) ;
  • Lee, Yeon-Kyung (Department of Food Science and Nutrition, Kyungpook National University)
  • Published : 2009.04.30

Abstract

This study investigated the microbial safeties and germination rates of five domestic sprout species(alfalfa, broccoli, clover, red cabbage, and red radish) grown from disinfected seeds. The 48 h germination rates of all seeds were over 90%, regardless of treatment. Seed total plate count(TPC) and coliform levels were reduced significantly(p<0.05) by treatment with 20,000 ppm calcium hypochlorite solution at $25^{\circ}C$ for 15 min, following FDA recommendations. However, after germination, all sprouts regardless of treatment exhibited bacterial counts of $10^7-10^8CFU/g$. Listeria monocytogenes was detected at $10^3-10^4CFU/g$ on germinated non-disinfected clover seeds at days 1, 2, and 5. In conclusion, although sprout germination from disinfected seeds potentially permits the growth of sprouts with lower pathogen counts, there were no significant differences in TPC or coliform levels between sprouts grown from disinfected seeds and control sprouts. Further work is needed to improve the microbial safety of cultivated sprouts and to find optimal conditions for seed germination.

본 연구에서는 새싹종자 소독처리 여부에 따른 재배기간별 미생물 오염도 수준을 파악하고, 종자소독이 발아율에 미치는 영향을 분석하였다. 수입산 새싹종자 알팔파(alfalfa), 브로콜리(broccoli), 클로버(clover), 적양배추(red cabbage), 적무(red radish) 5종에 대하여 소독제 처리 여부에 따른 발아율과 재배기간별 미생물 분석을 실시하였다. 소독제 종류에 관계없이 새싹종자(알팔파, 클로버, 적무)는 48시간 후 90% 이상 높은 발아율을 보였다. 종자 소독 시 식중독균은 검출되지 않았고, 대조군에 비하여 유의하게 낮은 미생물 수준을 보였으나, 발아과정에서 일반세균, 대장균군 모두 $10^7-10^8CFU/g$으로 종자소독 여부에 관계없이 종자에 비하여 유의하게 높은 오염 수준을 나타내었다(p<0.05). 또한 종자 소독하지 않은 클로버에서 Listeria monocytogenes 이 검출되었다. 따라서 새싹채소의 위생적인 안전성을 개선하기 위하여 미국 FDA 권고에 따라 재배전 종자의 소독이 필요하며, 발아과정의 HACCP 관리계획을 마련하여 중점적으로 관리하는 것이 필요하겠다.

Keywords

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