热辅助超声波处理对猕猴桃浊汁的杀菌效果及品质影响研究

Study on the Sterilization Effect and Quality of Cloudy Kiwifruit Juice Treated by Thermalassisted Ultrasonic

针对热杀菌猕猴桃浊汁中营养成分损失严重的问题,本试验对不同热辅助超声波处理工艺参数对猕猴桃浊汁理化特性的影响及杀菌效果进行研究,并优化最佳工艺参数。以猕猴桃浊汁为样品,选取猕猴桃浊汁的理化指标及杀菌率为响应值,以超声功率、超声时间、温度为因素,进行响应面试验,在筛选猕猴桃浊汁理化特征指标的基础上,建立杀菌率及猕猴桃浊汁理化特征指标模型并优化得出最佳工艺参数。结果表明,猕猴桃浊汁的理化特征指标为叶绿素保存率、PPO活性、△E值、糖酸比;最佳工艺参数为:超声功率420 W、超声时间30 min、温度60℃,在此条件下,猕猴桃浊汁的叶绿素保存率为30.99%、PPO活性为19.48 U·mL^(-1)、△E值为4.43、糖酸比为6.17、杀菌率为95.68%。本研究为热辅助超声波技术应用于猕猴桃浊汁的加工提供了理论依据和技术指导。

To solve the serious loss of nutrients in heat-sterilized kiwifruit juice,the effects of different heat-assisted ultrasonic treatment process parameters on the physicochemical characteristic indexes of kiwifruit juice and its sterilization effect were studied,and the optimal process parameters were obtained.Taking cloudy kiwifruit juice as sample,the physicochemical indexes and antibacterial rate were used as response values to optimize the conditions of ultrasonic power,ultrasonic time and temperature,the models of bactericidal rate and physicochemical characteristics of cloudy kiwifruit juice were established based on the extracted physicochemical characteristic indexes of cloudy kiwifruit juice.The results showed the physicochemical characteristic indexes were preservation rate of chlorophyll,PPO activity,ΔE value,and the ratio of sugar to acid.The optimal parameters for thermalassisted ultrasonic treatment of cloudy kiwifruit juice were as follows:the ultrasonic power was 420 W,the ultrasonic time was 30 min and the temperature was 60℃,and the preservation rate of chlorophyll was 30.99%,PPO activity was 19.48 U·mL^(-1),ΔE value was 4.43,the ratio of sugar to acid was 6.17,and the antibacterial rate was 95.68%.This study provides a technical guidance for the processing and production of cloudy kiwifruit juice.