Abstract:

In order to investigate the effect of roasting on the flavor of black sesame， gas chromatography-ion mobility spectrometry （GC-IMS） was used to analyze the flavor differences among unroasted， lightly roasted， moderately roasted and heavily roasted black sesame. The results showed that the black sesame samples with different roasting degrees could be better distinguished by GC-IMS technique， and a total of 52 volatile flavor substances were characterized by GC-IMS. Aldehydes， ketones and esters contributed to the flavor of roasted black sesame， and their types and contents increased gradually with the roasting process. Pyrazines， pyrroles and furans were the main aroma of roasted black sesame， showing strong nutty， roasted and burnt aromas， and their contents were higher in the later stages of roasting. The multivariate statistical analysis was able to effectively discriminate between black sesame samples with different roasting degrees， and 13 different aroma compounds were screened out. The cluster analysis based on 13 different compounds showed similar results with GC-IMS result. In conclusion， the flavor fingerprint profiles of black sesame at different roasting levels were constructed using GC-IMS technique， which provided theoretical references for the roasting process and quality improvement of black sesame.

Key words: black sesame, roasting degree, flavor, gas chromatography-ion mobility spectrometry

摘要：

为探究焙炒程度对黑芝麻风味的影响，采用气相色谱-离子迁移谱（gas chromatography-ion mobility spectrometry，GC-IMS）对未焙炒、轻度焙炒、中度焙炒和重度焙炒的黑芝麻进行风味差异分析。结果表明，不同焙炒程度黑芝麻样品可通过GC-IMS技术得到较好地区分。GC-IMS共定性出52种挥发性风味物质，其中醛酮类、酯类物质对焙炒黑芝麻风味贡献较大，随着焙炒过程的进行其种类和含量逐渐增加；吡嗪类、吡咯类、呋喃类物质是焙炒黑芝麻的主体香味，呈现出浓郁的坚果香、焙烤香和焦香，这些物质在焙炒后期含量较高。通过多元统计分析能够有效地判别不同焙炒程度的黑芝麻样品。并筛选出13种差异香气化合物，根据这13种差异化合物进行聚类分析，聚类结果与GC-IMS结果相似。综上，利用GC-IMS技术，构建了不同焙炒程度黑芝麻风味指纹谱图，为黑芝麻焙炒工艺优化、产品品质提升提供了理论参考。

关键词: 黑芝麻, 焙炒程度, 风味, 气相色谱-离子迁移谱