半干鲐鱼片冷风干燥工艺优化及货架期预测

实验以鲐鱼为原料,分析了冷风干燥工艺参数对半干鲐鱼片品质和风味的影响,通过U^*₉(9⁴)均匀设计实验,以不同的干燥工艺因素(温度、相对湿度、风速)为自变量,测定半干鲐鱼片的挥发性盐基氮值(TVB-N值)、菌落总数(TVC)与硫代巴比妥酸值(TBA值),进行感官评价,并建立干燥条件下的回归模型,对其结果进行综合分析,确定冷风干燥工艺的最优参数组合,并结合一级动力学模型与Arrhenius方程,研究其货架期预测模型。结果表明:温度、风速对TVB-N值有显著影响(p<0.05),温度对TBA有显著作用(p<0.05)。半干鲐鱼片冷风干燥工艺的最优条件为温度15℃,风速2.4 m/s,相对湿度25%。在此条件下验证得到实测值与预测值的一致性较好,TVB-N、TBA值误差分别为0.71%、1.16%。半干鲐鱼片干燥时间为21 h,TVB-N值为25.33 mg/100 g,TVC为5.93×10³ CFU/g,TBA值为1.11 mg/kg,感官评分为94.38分,鲜度好,风味佳。在-5~10℃范围内,建立的TVB-N值、TVC、TBA值与贮藏时间的动力学模型有较高拟合度,选用TVB-N、TBA值作为评判指标,可以准确预测半干鲐鱼片的货架期,本研究结果可为半干鲐鱼片的工业化生产提供理论依据。

Optimization of the cold air drying conditions and prediction on shelf-life of half-dried Scomber japonicus fillets

In order to investigate the effect of cold air drying parameters on the quality and flavor of half-dried Scomber japonicus fillets, Scomber japonicus were used as materials and tested by uniform design experiments of U*₉(94).The three different drying conditions(temperature, relative humidity and cold-air speed)were used as the independent variables. The optimal parameters of cold drying were determined by regression equation models with comprehensive analysis, which were established by the determination of the contents of total volatile basic nitrogen(TVB-N), aerobic plate count(TVC), thiobarbituric acid(TBA)and sensory quality of half-dried Scomber japonicus fillets. The shelf-life prediction models were studied by combining with the first order kinetic model and Arrhenius equation. The results showed that drying temperature and cold-air speed had an effect on TVB-N value(p<0.05)and drying temperature significantly affected the contents of TBA(p<0.05). Based on the regression equation models, the optimal conditions of drying were determined as follows:cold-air speed 2.4 m/s, temperature 15℃, humidity 25%. Under the optimal condition, the measured values of TVB-N and TBA were in good agreement with the predicted values, and the errors of TVB-N and TBA value were 0.71% and 1.16%, respectively.Under this optimized conditions, the time of cold air drying were 21 h, TVB-N value 25.33 mg/100 g, TVC was 5.93×103 CFU/g, TBA value was 1.11 mg/kg and sensory score was 94.38.The kinetic models between TVB-N、TVC、TBA value and storage time, built from-5 to 10℃, had a good fitting degree. TVB-N and TBA value were chosen to predict the remaining shelf-life of half-dried Scomber japonicus fillets.This research will provide a theoretical basis for production in industrial scale of half-dried Scomber japonicus fillets.