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Identification of electron beam-resistant bacteria in the microbial reduction of dried laver (Porphyra tenera) subjected to electron beam treatment

전자선 처리에 따른 마른 김(Porphyra tenera)의 미생물 저감화 효과와 저항성 세균의 동정

  • Kim, You Jin (School of Food Science and Biotechnology, Kyungpook National University) ;
  • Oh, Hui Su (School of Applied Biosciences, Kyungpook National University) ;
  • Kim, Min Ji (School of Food Science and Biotechnology, Kyungpook National University) ;
  • Kim, Jeong Hoon (School of Applied Biosciences, Kyungpook National University) ;
  • Goh, Jae Baek (School of Applied Biosciences, Kyungpook National University) ;
  • Choi, In Young (School of Food Science and Biotechnology, Kyungpook National University) ;
  • Park, Mi-Kyung (School of Food Science and Biotechnology, Kyungpook National University)
  • 김유진 (경북대학교 식품공학부) ;
  • 오희수 (경북대학교 응용생명과학부) ;
  • 김민지 (경북대학교 식품공학부) ;
  • 김정훈 (경북대학교 응용생명과학부) ;
  • 고재백 (경북대학교 응용생명과학부) ;
  • 최인영 (경북대학교 식품공학부) ;
  • 박미경 (경북대학교 식품공학부)
  • Received : 2015.12.24
  • Accepted : 2016.01.12
  • Published : 2016.02.28

Abstract

This study investigated the effect of electron beam (EB) treatment on the microbial reduction of dried laver (Porphyra tenera) and identified EB-resistant bacteria from the treated dried laver. After EB treatments of 4 kGy and 7 kGy, the numbers of total bacteria and EB-resistant bacteria were measured using tryptic soy agar and mannitol salt agar, respectively. The morphological and biochemical characteristics of each isolated EB-resistant bacteria were investigated and these bacteria were identified. Compared to the control ($1.5{\pm}0.2){\times}10^6CFU/g$, the total bacterial number was significantly decreased to ($5.4{\pm}0.5){\times}10^4CFU/g$ and ($1.1{\pm}0.6){\times}10^4CFU/g$ after EB treatments of 4 kGy and 7 kGy, respectively. With a higher EB dosage, the number of red colonies was almost same, whereas the number of yellow colonies was significantly decreased to ($3.3{\pm}1.2){\times}10^3CFU/g$ and 0 CFU/g for 4 kGy and 7 kGy, respectively. All red and yellow colonies were gram-positive cocci, catalase-positive, and resistant to 3% and 5% NaCl media. From the 16S rDNA sequence analysis, yellow and red colonies were identified as either Micrococcus flavus or M. luteus, with 99% similarity for the yellow colonies, and Deinococcus proteolyticus and D. piscis, with 99% and 97% similarity for the red colonies, respectively.

Acknowledgement

Supported by : 경북대학교

References

  1. Lee SK (1999) Effect of packaging on storage stability and chlorophyll contents of dried, roasted and roasted-seasoned laver during storage. J Fd Hyg Safety, 14, 134-139
  2. Lee HK, Song SH, Jeong IH (1987) Quality changes of dried lavers during processing and storage. Korean J Fish Aquat Sci, 20, 408-418
  3. Park CK, Kang TK, Shin SU (2001) The relationship between health and laver. Bull Fish Sci Inst Yosu National University, 10, 79-84
  4. Kim AJ, Shin JK (2014) Nonthermal sterilization of dried laver by intense pulsed light with batch system. Korean J Food Sci Technol, 46, 778-781 https://doi.org/10.9721/KJFST.2014.46.6.778
  5. Lee NY, Jo C, Chung HJ, Kang HJ, Kim JK, Kim HJ, Byun MW (2005) The prediction of the origin of microbial contamination in Kimbab and improvement of microbiological safety by gamma irradiation, Korean J Food Sci Technol, 37, 279-286
  6. Ahn HJ, Yook HS, Kim DH, Kim S, Byun MW (2001) Identification of radiation-resistant bacterium isolated from dried laver (Porphyra tenera). J Korean Soc Food Sci Nutr, 30, 193-195
  7. Kim BR, Kim AJ, Shin JK (2013) Effect of sterilization by intense pulsed light on radiation-resistant bacterium, Micrococcus roseus. Korean J Food Sci Technol, 45, 248-251 https://doi.org/10.9721/KJFST.2013.45.2.248
  8. Kang SG, Park SH, Ki HJ, Ham KS (2001) Chitosan treatment during the preparation of dried laver affects microbial growth and quality. J Chitin Chitosan, 6, 150-154
  9. Lee HJ, Byun HS, Kim JH, Park HY, Jung KJ, Lee TS (1999) Bacterial contamination of dried laver products. Bull Nat Fish Res Devel Ins, 57, 221-226
  10. Ahn JJ, Lee JE, Baek JY, Jeong IY, Kwon JH (2013) Identification of bulgogi sauce added with low quantity of electron beam-irradiated garlic powders by thermoluminescence analysis: an inter-laboratory study. Korean J Food Nutr, 42, 1857-1863 https://doi.org/10.3746/jkfn.2013.42.11.1857
  11. Farkas J, Farkas CM (2011) History and future of food irradiation. Trends Food Sci Tech, 22, 121-126 https://doi.org/10.1016/j.tifs.2010.04.002
  12. Kim JK, Song BS, Kim JH, Park JH, Byum EB, Lee JW (2013) Sterilization characteristics of ionizing irradiation and its industrial application. J Korean Musculoskelet Transplant Soc, 13, 49-57
  13. Kwon JH (2010) Safety and understanding of irradiated food. Korea Food Safety Research Institute, Seoul, Korea, 9-29