Studies On The Critical Production Technology Of The Prepared And Chilled Instant Sharkskin

Sharkskin, which is mainly from the outer skin of shark such as Mustelus manazo Bleeker, Mustelus griseus Pietschmann and Squalus acanthias Linnaeus or some other sharks, has rich nutrition and special health value. In this study, the sharkskin is used as raw materials to develop the the prepared and chilled instant sharkskin products which are nutritious and delicious, unique, healthy and safety. The research focuses on the the prepared and chilled instant sharkskin's critical production technology such as deodorization, increasing brittleness, and pre-sterilization combining bacteriostasis and preservation, to achieves the possibility of industrial production, and provides the theoretical basis for the industrialization of the prepared and chilled instant sharkskin. The main results as follows:(1) Optimization of the deodorization processing of the prepared and chilled instant sharkskinThe deodorization processing of the prepared and chilled instant sharkskin was studied in this thesis. Based on the single-factor experiments, the orthogonal designed experiment of L9(34)was adopted to optimize the deodorization processing of the chilled instant sharkskin by means of guzzy comprehensive judgement. The results showed that: by means of three procedures with the addition of citric acid, ginger juice, black tea, were 0.15%, 0.60%, 0.15% respective, following the proportion of fluid:sharkskin = 5:1(v/w)for 30 minutes, the fishy smell of sharkskin can be removed effectively and the products have got a good texture and flavor.(2) Study on the increasing brittleness of the prepared and chilled instant sharkskinThe main influence factors and their suitable range of the prepared and chilled instant sharkskin's brittleness were analyzed by single-factor tests. Basing on the rotating perpendicular combination experiments, the effects of the concentration of sodium hexametaphosphate solution (X₁), the blanching time (X₂) and colding time(X₃) on the brittleness of the prepared and chilled instant sharkskin were researched while the shearing force(Y) was determined as the target. Meanwhile, the optimum combination of three factors were also analyzed. Mathematical regression equation was established as follows: Y=25.09+1.59X₁+0.60X₂+1.43X₃-0.52X₁^2-1.96X₂²-0.85X₃²The results showed that the optimized parameters of increasing brittleness of the prepared and chilled instant sharkskin were as follows: concentration of sodium hexametaphosphate solution 4.0 g·L^-1, blanching time 2.0 min and ice cooling time 13 min, the prepared and chilled instant sharkskin was developed based on these conditions won the best brittleness with shearing force 26.52 N.(3) Study on the preservation technique of the prepared and chilled instant sharkskinIn this study, the hurdle antiseptic technology was used to preserve the prepared and chilled instant sharkskin. According to the defined pre-sterilization technique, suitable bacteriostat and consistence of the bacteriostat, the ratio between the components in the preservation solution was optimized using the total number of bacterial colony and the total volatile basic nitrogen(TVB-N) as evaluating index by orthogonal experimental design of L9(34).The results showed that: the pre-sterilization using 500 mg·kg–1 ozone consistence deal with the prepared and chilled instant sharkskin for 25min was effectual. The best proportion of the preservation solution was 0.060 g·kg–1 potassium sorbate, 0.4 g·kg–1Nisin and the pH≤4.5. Under this condition, the prepared and chilled instant sharkskin has got the best preservation effect, which can be stored in the condition at 0℃- 4℃for 60 days.