不同烘焙温度下核桃壳挥发性成分分析

Analysis of volatile compounds of walnut shell at different baking temperature

用体积分数75%的乙醇为提取液,采用热回流的方式获得不同烘焙温度下的核桃壳提取物,利用气相色谱-质谱联用技术(GC-MS)分别对挥发性成分进行分析,并以面积归一化法测定各个成分的相对含量。经不同烘焙温度处理后核桃壳的挥发性成分及含量差异较大,其中许多是重要的香料物质。160℃烘焙后6种主要香料成分为愈创木酚、香兰素、香草酸、丁香醛、4-羟基-2-甲氧基肉桂醛和3,5-二甲氧基-4-羟基肉桂醛的相对含量分别为1.97%、3.03%、5.08%、9.11%、31.42%和25.64%,总和高达76.25%;而不烘焙时对应成分的相对含量分别为0.91%、1.66%、2.03%、0.62%、3.07%和1.59%,总和只占9.88%。经烘焙后核桃壳中的主要香料物质的相对含量明显升高,显示了烘焙后的核桃壳在食品添加剂领域具有一定的利用价值,因此可将核桃壳烘焙后用于生产高附加值的香精香料。

Purpose： In order to provide a scientific evidence for the development and utilization of walnut shells as a food additive, walnut shell extract volatile components at different baking temperatures were analyzed. Methods： Walnut shell was extracted at different baking temperatures by thermal reflow with 75% ethanol. Then their chemical composition were separated and identified by GC-MS. Results： Walnut shell treated with different baking temperature are different in the volatile composition and content, many of which are of important flavor substances. After 160 ℃ baking, the six main flavor components content of guaiacol, vanillin, vanillic acid, syringaldehyde, 4-Hydroxy-2-me- thoxycinnamaldehyde, 3,5-Dimethoxy-4-hydroxycinnamaldehyde were 1.97% , 3.03% , 5.08% , 9.11% , 31.42% and 25.64% , respectively, and the total was 76.25% ; The above substance contents without baking were 0.91% , 1.66% , 2.03% , 0.62% , 3.07% and 1.59% , respectively, and the total was only 9.88%. Conclusions： After baking, the relative content of walnut shell main flavoring substances significantly increased. Therefore, baking can improve walnut shells value as a flavor essence.