Study On Water Holding Capacity Improvement Of Prepared Frozen Shrimp

In this research, frozen shrimp as raw material, the paper studied how to improve the water holding capacity of frozen shrimp. The study includes the development of water retaining agent, the thaw method of raw material, the discussion about temperature condition of soak test, the processing time of seasoning and the freezing method.First, the shrimp quality is assessed by the senses, texture and water holding capacity, salt, sodium carbonate, sodium bicarbonate, CaCl₂, citric acid, ascorbic acid and sodium citrate as comparison experiments were carried out. Above all of the reagents which can improving the strength of aquatic products. Through orthogonal test to determine the optimal formula: salt: sodium bicarbonate: sodium citrate for 37: 8:12. Use this aquasorb to product frozen shrimp which can get the macerate increase rate to 21.09%, defrost weightlessness rate for 2.12%, heating weightlessness rate for 28.93%, net weight ratio for 18.52%. For the prepared frozen shrimp, the macerate increase rate can reach 21.16%, defrost weightlessness rate for 3.16%, heating weightlessness rate for 33.01%, net weight ratio for 19.20%.Through comparison the phosphorus-free water retaining agent with phosphorus aquasorb we get that the phosphorus-free water retaining agent has obvious advantages.Secondly the influence of 0-5°c thaw, 5-10°c thaw, room temperature thaw and running water thaw to shrimps were investigated. We found that the thaw time is gradually shorten and the moisture content is gradually decreased in the above 4 thaw methods, but shrimps thawing under different methods have no difference in hardness, and low temperature and the rapid thawing can maintain the best elasticity. For processing recuperation frozen shrimp, 0-5°c thaw and 5-10°c thaws can obtain the optimum water quality shrimps. From the texture we can see that 5-10°c thaw and running water thaw can obtain optimal texture. In short, 5-10°c thaws for the best thaw condition.Finally, other factors that affect the quality of frozen shrimp were studied. We found that that shrimps impregnated for 6h under 0-5℃condition can get a lower loss rate of shrimps thawing, and shrimps can get a larger net weight gain rate and lower loss rate of shrimps heating. We also found that seasoning the shrimp in 10hs-24hs the shrimp can get the lowest loss rate of shrimps during thawing and heating. For the freeze of prepared frozen shrimp , when the core temperature of shrimps through 0℃to 5℃in 6 to 54 minutes, the shrimps have no significant differences .