压榨和精炼核桃油挥发性成分的比较及其电子鼻判别  

Comparison of volatile profiles in pressed and refined walnut oils and their discrimination by electronic nose

作　　者：周晔[1,2] 樊玮[2] 张俊佩[1,2] 裴东[1,2] 

机构地区：[1]中国林业科学研究院林业研究所林木遗传育种国家重点实验室国家林业局林木培育重点实验室,北京100091 [2]中国林业科学研究院林木遗传育种国家重点实验室,北京100091

出　　处：《中国油脂》2017年第2期130-134,140,共6页China Oils and Fats

基　　金：国家"十二五"科技支撑计划课题(2013BAD14B01)

摘　　要：利用气相色谱-质谱联用(GC-MS)结合电子鼻技术,从挥发性成分和整体气味两方面对冷榨、热榨和精炼核桃油进行了差异分析。结果表明:冷榨、热榨和精炼核桃油共有的挥发性成分中醛酮类占较大比例,相对含量分别为18.83%、21.86%和50.13%,其中又以己醛的相对含量最高;冷榨油的特异性挥发成分是酯类和萜类化合物,可能是核桃仁/油原始风味的基础物质;热榨油中吡嗪类等杂环类化合物相对含量最高,达42.95%;同时糠醛的生成表明Maillard反应的存在及戊糖组分对热榨油风味的重要影响;精炼油中挥发性成分以脂肪酸氧化产物醛酮类物质为主,核桃仁/油原始风味成分和Maillard风味成分在精炼后损失严重;基于挥发性成分的主成分分析和电子鼻检测结果一致,均能对3种核桃油进行有效区分。因此,可利用GC-MS结合电子鼻,从特征挥发性成分和整体气味两个方面对核桃油进行工艺控制和品质评价。From the aspects of volatile profiles and overall flavors, difference analysis of cold - pressed, hot - pressed and refined walnut oil were carried out by GC - MS combined with electronic nose. The re- sults showed that aldehydes and ketones accounted for a higher proportion in volatile profiles in cold - pressed,hot -pressed and refined walnut oil, representing 18.83% , 21.86% and 50.13% , respective- ly, in which the relative content of hexanal was the highest; esters and terpenoids were the specific vola- tile profiles in cold - pressed oil, which could be the basic substances of original flavors of walnut kernel and walnut oil; heterocyclics such as pyrazines were dominant in hot - pressed oil, which reached 42.95% of the total volatile amount. Meanwhile, the existence of furfural indicated the occurrence of Maillard reaction and the important role of pentose in the formation of roasted flavor of hot - pressed oil ; aldehydes and ketones derived from fatty acid oxidation was the main volatile profile in the refined oil, but there were serious losses of original flavors of walnut kernel and walnut oil and Maillard flavors after refining. The principal component analysis based on volatile profile was consistant with detection results of electronic nose, and both of them could discriminate three walnut oils effectively. There- fore, the combination of GC - MS with electronic nose could be used for process control and quality evaluation of walnut oil from aspects of volatile profiles and overall flavors.

关 键 词：核桃油 挥发性成分 风味 电子鼻 

分 类 号：O657.63[理学—分析化学] TS227[理学—化学]