不同加热处理对浆水挥发性成分变化的影响

Effect of different heat treatments on the volatile flavor components of Jiangshui

以发酵成熟的未加热处理原浆水为对照,将其分别在65℃/30 min、100℃/3 min和121℃/5 s加热处理后,采用顶空固相微萃取-气相色谱-质谱联用技术(headspace solid phase micro extraction-gas chromato graphymass spectrometry,HS-SPME-GC-MS)检测其挥发性成分,根据气味活度值分析了浆水的主体风味成分及其变化,并对浆水风味品质进行了感官评价,旨在探讨不同加热处理条件对浆水风味的影响。结果显示:原浆水主体风味成分有双戊烯、4-萜烯醇、α-松油醇、β-环柠檬醛;加热处理后的浆水挥发性成分变化较大,主要表现在醛类、酯类和含硫氮化合物的增多,且浆水主体风味成分也发生了较大变化,其中新增的反式-2-癸烯醛、反式-2-辛烯醛、2-庚烯醛等醛类以及异硫氰酸烯丙酯对加热处理后浆水的风味贡献较大,这些物质的增加很有可能是导致浆水风味发生劣化的主要原因。感官评定结果表明,相比其他2种热处理方式,65℃/30 min的加热处理对浆水风味的保持较好,更能获得消费者的认可。

The aim of this experiment was to explore the influence of different heat treatment conditions on the flavor of Jiangshui. The Jiangshui sample was heated at the three conditions of 65 ℃/30 min, 100 ℃/3 min and 121 ℃/5 s respectively. Volatile flavor components of Jiangshui samples were analyzed by headspace solid phase micro-ex- traction and gas chromatography-mass spectrum technique. The main aroma components were determined based on rel- ative oder activity value. Meanwhile the sensory and flavor quality of Jiangshui samples were evaluated. The results showed that the main flavor components of the fermented Jiangshui were dipentene, terpinen4-ol, α-terpineol, and β-cyclocitral. The flavor compounds in heated Jiangshui changed greatly compared with raw Jiangshui, especially the increase of the aldehyde, ester and sulfur-nitrogen -containing compounds. And the main aroma components of Jiangshui changed greatly, wherein the mainly increased components were （E） -dec-2-enal, trans-2-octen-1 -ol, （E） -hept-2- enal and allyl isothiocyanate, which made the significant contribution to the flavor of Jiangshui after heating, and probably was the main reasonforits flavor deterioration. Results from sensory evaluation showed that heat treatment at 65 ℃ for 15 min could result inabetter and accepted flavor of Jiangshui compared with the other two heat treatments.