Changes in the Quality Characteristics and Antioxidant Activities of Yoghurts Containing Spirulina during Storage

스피루리나 첨가 요구르트의 저장 중 품질 특성 및 항산화능의 변화

  • Son, Chan-Wok (Department of Food and Nutrition, Chungnam National University) ;
  • Shin, Yu-Mi (Department of Food and Nutrition, Chungnam National University) ;
  • Shim, Hyun-Jung (Department of Food and Nutrition, Chungnam National University) ;
  • Kim, Min-Hee (Department of Food and Nutrition, Chungnam National University) ;
  • Kim, Mi-Yeon (Department of Food and Nutrition, Chungnam National University) ;
  • Lee, Kun-Jong (Department of Food and Nutrition, Chungnam National University) ;
  • Kim, Mee-Ree (Department of Food and Nutrition, Chungnam National University)
  • 손찬욱 (충남대학교 식품영양학과) ;
  • 신유미 (충남대학교 식품영양학과) ;
  • 심현정 (충남대학교 식품영양학과) ;
  • 김민희 (충남대학교 식품영양학과) ;
  • 김미연 (충남대학교 식품영양학과) ;
  • 이근종 (충남대학교 식품영양학과) ;
  • 김미리 (충남대학교 식품영양학과)
  • Published : 2008.02.29

Abstract

The aim of this study was to evaluate the physicochemical, microbial, and sensory characteristics, as well as antioxidative activities of yoghurts containing spirulina powder, during storage at 4$^{\circ}C$. The pH of the yoghurts decreased until the 9th day of storage, but significantly increased by the 12th day. Total acidity also increased until the 9th day of storage, and then significantly decreased by the 12th day. Sugar content did not change significantly (approximately 18 $^{\circ}Brix$). Viscosity(cP) increased until the 6th day of storage, but had decreased at the 12th day. The viable bacterial cell counts of the control group decreased during storage. In contrast, the viable cell counts of the spirulina containing samples increased until the 9th day, and then decreased by the 12th day of storage. Antioxidant activity decreased in all groups, but the changes in antioxidant activity were lower in the spirulina groups than in the control group. According to sensory evaluations, the samples presented no significant differences during storage. Based on the above results, the optimum concentration of spirulina was determined as 0.25%. Also, the period of circulation of yoghurt containing spirulina was estimated to be 9 days at 4$^{\circ}C$.

Keywords