Characteristics and Sensory Optimization of Taro (Colocasia esculenta) under Different Aging Conditions for Food Application of Black Taro

흑토란의 식품재료화를 위한 숙성 조건에 따른 토란의 특성 및 관능 최적화

  • Jeon, Yu-Ho (Department of Food and Nutrition.Research Institute of Human Ecology, Seoul National University) ;
  • Lee, Ji-Won (Department of Food and Nutrition.Research Institute of Human Ecology, Seoul National University) ;
  • Son, Yang-Ju (Department of Food and Nutrition.Research Institute of Human Ecology, Seoul National University) ;
  • Hwang, In-Kyeong (Department of Food and Nutrition.Research Institute of Human Ecology, Seoul National University)
  • 전유호 (서울대학교 생활과학대학 식품영양학과.생활과학연구소) ;
  • 이지원 (서울대학교 생활과학대학 식품영양학과.생활과학연구소) ;
  • 손양주 (서울대학교 생활과학대학 식품영양학과.생활과학연구소) ;
  • 황인경 (서울대학교 생활과학대학 식품영양학과.생활과학연구소)
  • Received : 2015.12.08
  • Accepted : 2016.03.28
  • Published : 2016.04.30


The physicochemical properties, antioxidant capacities, and sensory optimization of taro (Colocasia esculenta) under different aging conditions were investigated to develop black taro. Black taro was processed in three steps (steaming: $95{\pm}3^{\circ}C$ for 1 h; aging: 85, 90, $95^{\circ}C$ for 20, 40, and 60 h; drying: $60^{\circ}C$ for 24 h) and ground into a powder for all experiments. Black taro showed an increased crude fiber content and browning index compared to raw taro. Calcium oxalate contents, reducing sugar contents, moisture contents, and lightness values were decreased during the processing of taro. Improvements in total polyphenol content and antioxidant activity (DPPH, ABTS, FRAP) were observed in the black taro samples aged at higher temperature. Response surface methodology was used for sensory optimization, and the optimum aging conditions with the highest acceptance values were found to be $88.73^{\circ}C$ for 39.50 h for taste, and $88.82^{\circ}C$ for 42.60 h for overall acceptance.


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