Changes in Physicochemical Characteristics of Kochujang Prepared with Different Koji during Fermentation

고오지 종류에 따른 식혜 고추장의 숙성 중 이화학적 특성 변화

  • Shin, Dong-Hwa (Faculty of Biotechnology, Chonbuk National University) ;
  • Ahn, Eun-Young (Faculty of Biotechnology, Chonbuk National University) ;
  • Kim, Yong-Suk (Faculty of Biotechnology, Chonbuk National University) ;
  • Oh, Ji-Young (Faculty of Biotechnology, Chonbuk National University)
  • 신동화 (전북대학교 응용생물공학부(농업과학기술연구소)) ;
  • 안은영 (전북대학교 응용생물공학부(농업과학기술연구소)) ;
  • 김용석 (전북대학교 응용생물공학부(농업과학기술연구소)) ;
  • 오지영 (전북대학교 응용생물공학부(농업과학기술연구소))
  • Published : 2001.04.30

Abstract

Physicochemical characteristics of kochujang prepared with meju, koji and mixture of meju and koji were analyzed during fermentation in order to improve quality of traditional sikhe kochujang. Amino nitrogen content, an index of kochujang quality, was remarkably higher in kochujang prepared with p-2 koji, p-1 koji, mixture of p-2 koji and meju. Titratible acidity of kochujang slightly increased and pH of kochujang increased until 40 days of fermentation and then decreased there after. Citric acid was found as a major organic acid followed in decreasing order by malic, oxalic, succinic, acetic and lactic acids. As a free sugar, maltose, glucose and fructose were detected. Free sugar content was higher in kochujang prepared with p-1 koji than the others. The major free amino acids were aspartic acid, glutamic acid, alanine, phenylalanine and arginine, and total free amino acid content was higher in kochujang prepared with koji, and mixture of meju and koji than the one with traditional meju only. In sensory evaluation, all tested groups did not show a significant difference. This result indicates that addition of koji to sikhe kochujang influences on taste components like free sugars and free amino acids, but decisively not on the sensory properties.

Keywords

kochujang;meju;koji;amino acid;organic acid