锦橙汁辐照和巴氏灭菌处理后相关品质的分析

为探讨辐照和巴氏杀菌对橙汁品质的影响,对锦橙汁分别进行1.4、2.8、5.6kGy3种不同剂量辐照及巴氏灭菌处理,使用固相微萃取-气质联用技术对挥发性成分进行分析,测定橙汁色度、pH值和Vc含量,并对橙汁香气进行感官评定。在鲜橙汁、巴氏灭菌汁和3种辐照样品中分别检测到了54、47、57、55和53种成分,2.8kGy剂量辐照处理后橙汁挥发性成分总峰面积最高,β-月桂烯、柠檬烯和γ-松油烯等橙汁特征香气物质经辐照后保持率高于巴氏灭菌。各种处理后Vc含量均有所下降,橙汁橙香均减弱。1.4kGy辐照后的橙汁感官评价结果最好,因此可以对橙汁进行低剂量辐照灭菌。

QUALITY OF JINCHEN ORANGE JUICE TREATED WITH IRRADIATION AND PASTEURIZATION

Jinchen orange juice was treated by pasteurization and irradiation (1.4, 2.8 and 5.6kGy) to study the effects of sterilization methods on quality of orange juice. The volatile compounds were analyzed by solid phase micro-extraction method combined with GC-MS. The juice color, pH and Vc content were determined, and sensory evaluation of the juice were evaluated. The results showed a total of 54, 47, 57, 55, 53 kinds of compounds were detected in fresh juice, pasteurized juice and 3 irradiated juices, respectively. The irradiated juices had bigger peak area of volatile compounds than pasteurized juice, and the biggest peak area was found in 2.8kGy irradiation sample.β-myrcene, D-limonene andγ-terpinene, which were the characteristic aroma compounds in orange juice, were detected a higher level in irradiation sample than pasteurization. Vc content and aroma decreased after all treatments. The sample after 1.4kGy treatment showed highest score in sensory evaluation. It was concluded that low dose irradiation could be used in sterilization processing of orange juice.