小磨芝麻香油制备过程中品质的变化

Quality change of ground fragrant sesame seed oil during preparation

为了更好地对小磨芝麻香油进行质控,在芝麻焙炒、石磨磨浆、水墩油3个主要工艺过程结束时取样,对不同工艺阶段芝麻油的色泽、酸值、过氧化值、脂肪酸组成及风味进行了检测。结果表明:水墩油过程使芝麻油有最大的a值和b值,分别为12.84和89.36;焙炒和石磨磨浆过程芝麻油的酸值不断降低,经水墩油之后又有所上升;与未焙炒的芝麻油相比,焙炒使芝麻油的多不饱和脂肪酸含量略有增加;电子鼻检测结果与GC-MS结果一致,焙炒和石磨磨浆过程所得芝麻油的风味相似,而水墩油使芝麻油风味物质种类增多,风味更强。综上,除焙炒过程外,水墩油也是影响小磨芝麻香油品质,特别是色泽和风味的关键环节,应加强对该阶段小磨芝麻香油风味物质变化与形成的研究。

In order to better control the quality of ground fragrant sesame seed oil,the color,acid value,peroxide value,fatty acid composition and flavor of sesame seed oil in different process stages were measured by sampling at the end of three main processes:sesame seed roasting,millstone grinding and oil separation by oscillation(including water adding and mixing).The results showed that the process of oil separation by oscillation made sesame seed oil have the largest a value and b value,which were 12.84 and 89.36,respectively.The acid value of sesame seed oil decreased continuously during roasting and millstone grinding,but increased after oil separation by oscillation.Compared with sesame seed oil obtained with unroasted sesame seed,roasting increased the polyunsaturated fatty acids content slightly.The results of electronic nose detection were consistent with those of GC-MS.The flavor of sesame seed oil obtained by roasting and millstone grinding was similar,while the variety of flavor substances in sesame seed oil increased and the flavor was stronger after oil separation by oscillation.In conclusion,besides the roasting process,oil separation by oscillation is also a key link that affects the quality of ground fragrant sesame seed oil,especially the color and flavor.It is necessary to strengthen the research on the change and formation of flavor substances in ground fragrant sesame seed oil at this stage.