Korean Journal of Food Science and Technology (한국식품과학회지)

Korean Society of Food Science and Technology (한국식품과학회)
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Changes of Microbiological and Physicochemical Characteristics of Doenjang Prepared with Low Salt Content and Gamma Irradiation

감마선 조사와 저염함량으로 제조한 된장의 미생물 및 품질특성 변화

  • Park, Byoung-Jun (Team for Radiation Food Science and Biotechnology, Korea Atomic Energy Research Institute) ;
  • Jang, Kyu-Sub (Department of Food Engineering, Chungnam National University) ;
  • Kim, Dong-Ho (Team for Radiation Food Science and Biotechnology, Korea Atomic Energy Research Institute) ;
  • Yook, Hong-Sun (Team for Radiation Food Science and Biotechnology, Korea Atomic Energy Research Institute) ;
  • Byun, Myung-Woo (Team for Radiation Food Science and Biotechnology, Korea Atomic Energy Research Institute)
  • 박병준 (한국원자력연구소 방사선식품.생명공학팀) ;
  • 장규섭 (충남대학교 식품공학과) ;
  • 김동호 (한국원자력연구소 방사선식품.생명공학팀) ;
  • 육홍선 (한국원자력연구소 방사선식품.생명공학팀) ;
  • 변명우 (한국원자력연구소 방사선식품.생명공학팀)
  • Published : 2002.02.01
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Abstract

Changes of microbiological and physicochemical characteristics of gamma irradiated Doenjang with low salt were studied. Samples were prepared by mixing the Doenjang and the Chungkukjang with 6% and 8% of salinity. The mixture was irradiated by gamma-ray with dose of 0, 5, 10, 20 kGy, and each sample was stored at $25^{\circ}C$ for 8 weeks. The results showed that the Bacillus cell was inactivated by $10^4-10^5\;cells/g$ with dose of 10 kGy, and yeast and Lactobacillus group were nearly eliminated by 10 kGy. The general quality of gamma irradiated low salt Doenjang, such as amino nitrogen, protease activity, and pH, were more stable than that of control during storage periods. The sensory evaluations showed that 8% (salt)-5 kGy and 6% (salt)-10 kGy irradiated samples were more acceptable than market purchased Doenjang. Therefore, it was considered that gamma irradiation was effective for maintaining better quality of low salt Doenjang and suitable radiation dose was 5 kGy in 8% salted, and 10 kGy in 6% salted sample.

숙성이 완료된 된장에 염도 4%의 청국장을 혼합하여 각각 염도 8%, 6%의 저염된장을 제조한 다음 0, 5, 10, 20 kGy의 감마선을 조사하여 상온에 보존하면서 보존 기간 중의 미생물 및 일반 품질 특성 변화를 살펴보았다. 미생물은 조사선량의 증가에 따라 유의적인 살균효과를 나타내어 Bacillus는 비조사구에 $10^9\;CFU/g$이던 것이 10 kGy에는 $10^5-10^6\;CFU/g$으로, 20 kGy에서는 $10^3 CFU/g$으로 감소하였고 보존기간 중 점차 증가하였다. 효모와 산생성 세균은 10 kGy 이상의 감마선 조사에 의하여 거의 제거되었으며 보존기간 중에도 검출되지 않았으나 비조사구 및 5 kGy 조사구에서는 증식하였다. pH, protease, 아미노태질소의 변화는 감마선 조사구가 비조사구에 비하여 안정적인 품질을 유지하였으나 6%-5 kGy 조사구는 보존 $6{\sim}8$주 후에 변패를 나타내었다. 시료의 관능평가 결과 8%-5kGy, 그리고 10 kGy의 감마선조사 시료에 대한 선호도가 높았으며 특히, 8%-5kGy의 시료는 시판 일반된장보다 높은 선호도를 보였다. 따라서 된장과 청국장을 혼합한 다음 감마선을 조사하여 관능 및 보존성이 우수한 저염된장을 제조하는데 필요한 적정 감마선 조사선량을 염도 6%에서는 10 kGy가, 염도 8%에서는 $5{\sim}10\;kGy$가 적합할 것으로 평가되었다.

Keywords

References

  1. Lee, H.C. Fermentation food. Sinkwang Press Co., Seoul, Korea pp. 28-121, 260-287 (1999)
  2. Shon, D.H., Lee, S.H. and Ahn, C.W. Screening of antithrombotic peptides from soybean paste by the microplate method. Korean J. Food Sci. Technol. 28: 684-688 (1996)
  3. Choi, S.Y., Choi, M.J., Lee, J.J., Kim, H.J., Hong, S.S., Chung, K.S. and Lee, B.K. Growth suppression effect of traditional fer-mented soybean paste (Doenjang) on the various tumor cells. J. Korean Soc. Food Sci. Nutr. 28: 458-463 (1999)
  4. Lee, B.K. Immunomodulation materials of fermented soybean products. Lecture 3, 2nd Symposium for Soybean Fermentation Foods, The Research Institute of Soybean Fermentation Foods, Yeungnam Univ. Korea (1999)
  5. Kim, W.K., Choi, K.H., Kim, Y.T., Park, H.H., Choi, J.Y., Lee, Y.S., Oh, H.L, Kwon, I.B. and Lee, S.Y. Purification and charac-terization of fibrinolydc enzyme produced from Bacillus sp. strains CK 11-4 screened from Chungkookjang. Appl. Environ. Microbiol. 62: 2482-2488 (1996)
  6. Joo, H.K. Current trends and problems of fennented soybean products. Lecture 1, 1st Symposium and Expo for Soybean Fer-mentation Foods, The Research Institute of Soybean Fermentadon Foods, Yeungnam Univ. Korea (1998)
  7. Choi, B.S., Kim, E.J. and Park Y.S. Study on sodium intake and preference for salty taste in college women. J. Korean Soc. Food Sci. Nutr. 26: 154-160 (1997)
  8. Kim, J.D., Choi, M. and Ju, J.S. A study on correladon between blood pressure and diatry Na, K intakes pattem in the family members of normal and cerebrovascular disease padents. J. Korean Soc. Food. Nutr. 24: 24-29 (1995)
  9. Lee, S.W., Shin, S.Y. and Yu, T.J. Effects of the ethanol contents on the preparation of low salt Doenjang. Korean J. Food Sci. Technol. 17: 336-339 (1985)
  10. Chiou, R.Y., Femg, S. and Beuchat, L.R. Fermentation of low-salt miso as affected by supplementation with ethanol. Intemadonal J. Food Microbiol. 48: 11-20 (1999) https://doi.org/10.1016/S0168-1605(99)00033-1
  11. Byun, M.W., Kim, D.H., Yook, H.S., Cha, B.S. and Kim, J.O. Changes in microbiological and general qualities in gamma irra-diated Doenjang (Fennented Soybean Paste). Food Sci. Biotech-nol. 10:7-11 (2001)
  12. Kim, D.H., Yook, H.S., Youn, K.C., Cha, B.S., Kim, J.O. and Byun, M.W. Changes of microbiological and general quality char-acteiistics of gamma irradiated Chungkukjang. Korean J. Food Sci. Technol. 32: 896-901 (2000)
  13. Kim, D.H., Yook, H.S., Youn, K.C., Sohn, C.B. and Byun, M.W. Changes of microbiological and general quality characteristics of gamma irradiated Kochujang (Fermented Hot Pepper Paste). Korean J. Food Sci. Technol. 33: 72-77 (2001)
  14. Kim, D.H., Lee, K.H., Yook, H.S., Kim, J.H., Shin, M.G. and Byun, M.W. Quality characteristics of gamma irradiated grain shape improved Meju. Korean J. Food Sci. Technol. 32: 640-645 (2000)
  15. Yook, H.S., Lee, E.M., Kim, D.H., Lee, K.H., Lee, H.J., Lee, Y.N. and Byun. M.W. Genotoxicological safety on water-soluble fraction of gamma irradiated Korean soybean fermentation foods. Korean J. Food Hye. Safety 15: 297-303 (2000)
  16. Furuta, M., Ohashi, I., Oka, M. and Hayashi, T. Irradiation effects on hydrases for biomedical applicadons. Radiat. Phys. Chem., 57: 455-457 (2000) https://doi.org/10.1016/S0969-806X(99)00414-4
  17. Collins, C.H., Lyne, P.M. and Grange, J.M. Microbiological methods, 6th ed., pp. 330-334. Butterworths, London, Great Britain (1989)
  18. Difco Laboratoiies. Difco Manual 10th ed., Detroit Michigan 48232 USA p. 492 (1984)
  19. Difco Laboratories. Difco Manual 10th ed., Detroit Michigan 48232 USA p. 689 (1984)
  20. AOAC Official method of analysis. 15th ed., The Association of Offcial Analytical Chemists, Washington, DC, USA (1990)