Monitoring microbiological contamination, pre-decontamination, and irradiation status of commercial dried laver (Porphyra sp.) products

시판 유통 김의 미생물 오염도, 사전 살균처리 및 전자선 조사 여부 확인

  • Lee, Eun-Jin (School of Food Science & Biotechnology, and Food Bio-industry Research Institute, Kyungpook National University) ;
  • Kim, Gui-Ran (School of Food Science & Biotechnology, and Food Bio-industry Research Institute, Kyungpook National University) ;
  • Lee, Hye-Jin (School of Food Science & Biotechnology, and Food Bio-industry Research Institute, Kyungpook National University) ;
  • Kwon, Joong-Ho (School of Food Science & Biotechnology, and Food Bio-industry Research Institute, Kyungpook National University)
  • 이은진 (경북대학교 식품공학부.식품생물산업연구소) ;
  • 김귀란 (경북대학교 식품공학부.식품생물산업연구소) ;
  • 이혜진 (경북대학교 식품공학부.식품생물산업연구소) ;
  • 권중호 (경북대학교 식품공학부.식품생물산업연구소)
  • Received : 2016.07.28
  • Accepted : 2016.10.08
  • Published : 2017.02.28


Eighteen commercial laver (Porphyra sp.) products were purchased from Korean market and were monitored for their microbial contamination, pre-decontamination, and luminescence properties. The laver samples showed considerable variation in their microbial contamination, from $10-10^7CFU/g$ of total aerobic counts, <$10-10^2CFU/g$ of coliforms in 4 dried laver samples, and <$10-10^6CFU/g$ of yeasts and molds except in 3 samples. In addition, $10^2CFU/g$ of Bacillus cereus was found in one sample. DEFT/APC analysis was suitable for demonstrating whether the samples were pre-decontaminated or not, with DEFT/APC values lower than 2.0 log for non-heated samples and 1.0-8.5 log for heatprocessed samples. In photostimulated luminescence (PSL) calibration, 15 samples irradiated at 1 kGy showed positive (irradiated) values more than 5000 PCs. Furthermore, thermoluminescence (TL) analysis by separating the marker minerals from samples revealed the potential to be employed in identifying irradiation status by determining $1^{st}$ TL glow at $125-175^{\circ}C$ and TL ratio ($TL_1/TL_2$) of all the samples.


Supported by : 한국연구재단


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