Study On Extraction Of Gelation From Chub Scale And The Product Quality

Fish scale has abundant collagen and has a proportion of 20%～40%,which is profitable for extracting gelatine.It has relatively lower lipid,so it is more beneficial for extracting and purifying collagen compared with pigskin and cowskin.In this paper,a new technology for extracting glue from chub scale has been developed in the principle of economy;the residue form the liquid is hydrolysed in order to utilize comprehensively;then dry the fish scale glue liquid into a product which can be applied directly;then determined qualities of the glue;at the end,congelation quality of the gel has a try to an application.The best process routes—combinational method of acid-alkali processing and hot water extraction for extracting glue from chub scale has been determined.This paper obtained the best process parameters:acid 1:20,acid concentration 3%,acid action time:6h,raw material: alkali 1:20,alkali concentration 3%,alkali action time:12h,water extraction time 5h,water extraction twice.The production cycle can been reduced to 1 day in contrast to 30～40 days if use the traditional method.In addition,the purity of glue got from this new method is high,meanwhile,the quality is favorable.Glue strength can come to 1609.4g and its viscosity is 20.58mPa·s,which is 1.74 fold and 1.45 fold compared with gelatin of reagent.Residue hydrolyzation.This paper has studied the technology to hydrolyze chub scale residue using papain.According to the degree of hydrolysis,choose enzyme volume 1:10,hydrolysis temperature 65℃,hydrolysis time 4h,substrate concentration 2% finally.Results showed that spray drying is better than freeze-drying.The parameters were: entrance air temperature 190℃,exit air temperature 90℃,liquid concentration 15%,feed temperature 50℃, feed rate 10mL·min-1.The product has good colour and stickability.Indexes measurement.Results showed the glue got from the new method has good hydroscopic property,emulsion stability,foaming capacity,foam stability and it is high in gelatin strength and viscosity.Moreover,each index is better than the gelatin of reagent. Viscosity of fish gel is inverse ratio to temperature,and direct ratio to its concentration.When pH is acidity viscosity keeps steadily.When pH is 6 it gets a highest value,and it will fall down then increase when pH augments.Application of fish gelatine.Through sensory perception testing,fish gel jelly can be proved it is feasible.The jelly on the best condition has a good texture,flexibility, diaphaneity,smell and so on.The condition is fish gel 5%,granulated sugar 10%,citric acid 0.4%,essence 0.015%,pigment 0.01%, sweety 0.015%,90℃,10min.