Storage quality and shelf life of frozen shrimp
H. K. KIM1, Y. Jeong2, M. Kim2, and J. H. Kwon3. (1) Food Chemistry & Biotechnology, Korea Food Research Institute, San 46-1, Baekhyun-Dong, Bundang-Ku, Songnam, Kyonggi-Do, 463-420, South Korea, (2) Dept. of Food Science and Nutrition, Dankook University, San 8 Hannam-Dong, Yongsan-Ku, Seoul, 140-714, South Korea, (3) Dept. of Food Science and Technology, Kyungpook National University, 1370 Sankyuk-Dong, Book-Ku, Taeku, 702-701, South Korea
Shrimp is one of the most popular seafoods and it's consumption is increasing in Korea. Even though fresh shrimp is preferred by consumers, frozen shrimp is attaining a consumer's acceptance gradually because of better price, and long and safe storage life comparing to fresh shrimp. In this study, the commercial frozen shrimp was chemically characterized at different temperatures and storage time, and the shelf life was determined by sensory evaluation.
The objectives of this study were to investigate the effect of storage temperature and storage time on: (1) changes in chemical characteristics and pH (2) oxidative and freshness stability, and (3) shelf life of commercial shrimp by sensory evaluation.
Frozen shrimps were purchased in the market, repackaged in high barrier oriented nylon laminated polyethylene pouches and then stored up to six months at different storage temperatures (0, -5, -10 and -18°C). Samples were thawed at room temperature for the analyses. Oxidative rancidity of frozen shrimp samples was examined by thiobarbituric acid (TBA) test and freshness by a volatile basic nitrogen (VBN) analysis at 0, 1, 2, 3, 4, 5, and 6 months of storage. Sensory evaluation was performed using hedonic scale method.
The TBA values increased with time and were highest at 0°C. There was an increase in VBN with time at all storage temperatures. Color, flavor and overall satisfaction scores of frozen shrimp correlated highly and consistently with TBA values. The shelf life of frozen shrimp determined by sensory evaluation was 2.1 months at 0°C, 5.3 months at -5°C and 6.8 months at -10°C, respectively.
The results of this study will be useful for predicting the shelf life of frozen food products.
Session 88F, Refrigerated & Frozen Foods