不同灭菌工艺对鲜榨柚汁品质及挥发性成分的影响

本文对三种果汁杀菌工艺(热杀菌、UHT杀菌和超高压杀菌)对柚果汁pH、Brix、总酸、维生素C、微生物、感官和香气的影响进行比较。与对照组相比,不同灭菌处理方法对于果汁理化指标并无显著性差异(P<0.05),相对于超高压灭菌,经热杀菌和UHT处理的柚汁的维生素C含量发生显著性降低(P<0.05),这表明超高压处理更利于果汁中维生素C的保存。结合感官评价及GCMS对挥发性成分分析,热处理状态下果汁清香感、柚香感强度出现明显下降,过熟味强度出现明显上升,主要是由于热处理后果汁中醛类、萜烯类成分浓度下降而芳樟醇氧化物浓度增加。该研究结果可为果汁加工提供参考。

The Effects of Different Sterilization Processes on the Quality and Volatiles of Fresh Pomelo Juice

This paper is mainly studying the effects of different sterilization processes(pasteurization,ultra-high temperature instantaneous sterilization(UHT)and high pressure processing(HPP))on the quality of pomelo juice.The effects of different sterilization methods on the physical and chemical indexes(such as pH,Brix,total acid,microbial,sensory and aroma of fruit juice.)were compared.Compared with the control group,there was no significant difference in the physical and chemical properties of fruit juice(P<0.05).Compared with HPP,the concentration of vitamin C treated by pasteurization and UHT decreased significantly(P<0.05).This indicated that HPP was more beneficial to protect vitamin C in juice during the sterilization.Combined with the sensory evaluation and GCMS analysis of the volatile components,under the condition of heat treatment,the intensity of fresh and pomelo flavor decreased significantly,while the intensity of cooked odour increased significantly,mainly because the concentration of aldehydes and limonene in the juice decreased and the concentration of linalool oxide increased after heat treatment.The results of this study can provide experimental reference for juice processing.