热处理刺梨汁香气物质的SPME-GC-MS检测与主成分分析

在模糊数学综合评判法的基础上，采用固相微萃取-气相色谱-质谱联用（solid-phase microextraction-gas chromatography mass spectrometry，SPME-GC-MS）技术检测热处理前后刺梨汁挥发性成分，结合主成分分析法对刺梨汁的挥发性成分进行分析。结果表明：热处理前后5?个样品经SPME-GC-MS检测出65?种挥发性物质，主要以酯类、醇类、烯类为主。经不同升温加热处理，刺梨汁的挥发性成分种类及相对含量均呈先增加后减少趋势，其中70?℃、30?min处理组的挥发性成分种类最多，为61?种，相对含量为89.22%，其种类与相对含量最接近刺梨原汁。主成分分析得出刺梨汁主要香气成分为酯类、烯烃类物质，70?℃、30?min热处理组在香气成分上与原汁聚为一类，香气成分含量与种类相差不大，与模糊数学综合评判法结果相一致，因此，可以得出70?℃、30?min热处理条件是刺梨汁热加工过程中的最佳条件。

Analysis of Volatile Aroma Compounds of Heated Rosa roxbuighii Tratt Juice by Solid-Phase Microextraction Combined with Gas Chromatography-Mass Spectrometry and Principal Component Analysis

Fuzzy comprehensive evaluation was employed in the present research to assess the sensory quality of heated Rosa roxburghii Tratt juice. Subsequently, the volatile aroma components of raw and heated juice samples were determined by solid-phase microextraction (SPME) combined with gas chromatography-mass spectrometry (GC-MS) and analyzed by principal component analysis (PCA). Results showed that a total of 65 volatile components were detected from raw juice and 4 heated samples, dominated by aldehydes, alcohols and alkenes. The number and amount of volatile compounds in the heated samples increased first and then decreased; 70 ℃, 30 min heated juice contained the largest number (61) of volatile compounds, accounting for 89.22% of the total, and its volatie composition was most similar to that of raw juice. The main aroma components identified by PCA were esters and alkenes. These findings were consistent with fuzzy comprehensive evaluation. Therefore, heat treatment at 70 ℃ for 30 min were the optimal conditions for thermal processing of R. roxburghii Tratt juice.