Study On Processing Technology Of Double Protein Nutrient Vegetable Minced Fish Products

This project takes fish surimi and purple cabbage as the main raw materials,and combines with "double protein project" to add soy isolate protein and whey protein,in order to develop a kind of soft,fresh and fragrant,with a long shelf life and rich nutrition double protein vegetable nutritional fish ball.The frozen surimi stored at-18℃ was thawed in a water bath at 5℃,10℃ 15℃,20 ℃,25℃ respectively.when the temperature reach 2℃,the minced fish center minced fish and determination of the pH value,volatile base nitrogen content,unfrozen water loss rate,whiteness value,quality and structure analysis of the five indicators,and scanning electron microscopy analysis to determine the minced fish best thawing temperature;The optimal addition amount of soybean protein,whey protein,vegetable juice and TG enzyme was selected by single factor test and orthogonal test.Different heating processes were selected to heat the fish balls.After cooling,the fish balls were left overnight in a constant temperature refrigerator at 4℃.On the next day,the optimal condition of heating method was selected according to the indexes of water retention,defrost water loss rate,sensory score and texture analysis.According to the national standard,the basic nutrient composition was determined and the amino acid composition was analyzed by the automatic amino acid analyzer.Taking fish balls without fresh-keeping liquid as the control group,the contents of volatile basic nitrogen in the samples were measured by automatic kjelddinometer,and the optimal fresh-keeping concentrations of lysozyme,water-soluble chitosan and lactic acid bacteria streptococcus were determined by single factor test.On this basis,response surface optimization was carried out to select the best proportion of the compound fresh-keeping liquid.The Arrhenius equation was used to predict the shelf life of fish balls at low temperature and normal temperature.The results showed that:(1)the optimum thawing temperature of frozen surimi was 10℃;(2)the optimal addition amount of main ingredients of fish balls was soybean protein 5%,whey protein 1%,purple cabbage vegetable juice 12%and TG enzyme 0.5%.(3)the optimal heating conditions are as follows:the first stage heating temperature is 45℃ and the time is 40 min;the second stage heating temperature is 90℃ and the time is 20 min;(4)the optimal ratio of composite fresh-keeping liquid was:chitosan 3.11 g/kg,lactic acid bacteria streptococcus 0.26 g/kg,lysozyme 0.26 g/kg at room temperature;Chitosan 2.51 g/kg,lactic acid streptococcus 0.27 g/kg,lysozyme 0.26 g/kg at 4℃.(5)when the product is stored at 25℃,the theoretical shelf life is 18 days.When stored at 4℃,the shelf life is 59 days.The preparation of double protein vegetable fish ball not only responds to the national "double protein project",but also increases the economic utilization value of chub surimi,broadens the application range of purple cabbage,and has a broad development prospect.