Optimization of vacuum frying technology for shrimps based on fuzzy mathematics sensory evaluation

ObjectiveThe present study aimed to optimize the vacuum frying technological parameters for Litopenaeus vannamei and provide theoretical basis for development of L. vannamei instant food. MethodFresh L. vannamei was the raw materials, and fuzzy mathematic sensory evaluation(Y) was indicator. Based on single-factor experiment, vacuum frying temperature(A), vacuum frying time(B) and vacuum degree(C) were selected as independent variables and the vacuum frying technology was optimized by response surface methodology. ResultWeight analysis for vacuum fried shrimps was based on sensory evaluation and the weight collection was K=color 0.205, shape 0.125, greasy sense 0.270, crisp degree 0.400. The quadratic multinomial regression equation was established as follow:Y=71.76+5.40A+5.75B+7.34C+3.89AB+5.43AC+6.47BC-4.90A2-3.80B2. Vacuum frying temperature, vacuum frying time, vacuum degree as well as interaction between vacuum frying time and vacuum degree had extremely significant effects on sensory score(P<0.01). The effects of interactions between vacuum frying temperature and vacuum frying time, vacuum frying temperature and vacuum degree was significant(P<0.05). Through response surface analysis, the optimal conditions were as follows:vacuum frying temperature 110 ℃, vacuum frying time 50 min and vacuum degree 0.09 MPa. Under this condition, the sensory score was 90.09±1.27, which was close to the predictive value(94.51). The product had uniform and glossy color, crispy taste, moderate oil content and complete shape. ConclusionThe optimized vacuum frying technology for shrimps by response surface methodology is easy to operate, the optimized condition is accurate and the display of results is intuitive. The influence rule of various factors on indicator can be analyzed by regression equation, which can also be used in predicting actual production.