Study on processing and properties of fish scale jelly produced by heating in water

Processing and properties of fish scale jelly produced by heating in water with grass carp fish scale as raw material were studied. Orthogonal test with extraction temperature, extraction time, pH of water, ratio of fish scale to water as factors and collagen extraction rate, gel strength, ash extraction rate as dependent variables was conducted to ascertain the optimum processing conditions of fish scale jelly. The result showed the optimum conditions was the ratio of fish scale to water 1∶4, pH of water was 6, extraction temperature 100℃ and extraction time 2h. The dependent variables of the verification experiment were 54.06% ±2.38% collagen extraction rate , 0.76% ±0.05% ash extraction rate and (48.98 ±2.45) g gel strength. The physicochemical properties of fish scale jelly processed under the optimum conditions were (1.87±0.05) mPa·s viscosity , (14.73±0.31) ℃ gelling temperature and (23.33±0.30) ℃ melting temperature. Texture profile analysis showed the resulted fish scale jelly was softer and more elastic than ordinary fruit jelly. Therefore, fish scale jelly would be a kind of healthy snack with great potential.