菜籽油加工过程中香兰素含量的变化研究 Change of vanillin content during rapeseed oil processing

旨在明确菜籽油中香兰素来源以及不同加工工艺菜籽油中香兰素的本底水平，为市场监管提供理论支撑。首先对比分析了不同种植地油菜秸秆、果荚及油菜籽中香兰素含量，然后考察压榨法制取菜籽油各工序香兰素含量变化，并进一步分析炒籽温度和炒籽时间对油菜籽中香兰素含量的影响，最后测定不同工艺成品菜籽油中香兰素的含量。结果表明：不同种植地油菜秸秆、果荚及油菜籽中香兰素含量差异较大，从油菜不同生长部位来看，油菜秸秆中香兰素含量最高，其次是果荚，油菜籽中香兰素含量最低；在压榨法制取菜籽油过程中，蒸炒后油菜籽中香兰素含量大幅增加，菜籽原油中的香兰素含量低于预榨饼中的，随着精炼的进行，菜籽油中的香兰素含量逐渐降低；随着炒籽时间延长和炒籽温度升高，油菜籽中香兰素含量逐渐增加，160 ℃炒籽50 min时，安徽安庆和内蒙古海拉尔油菜籽中香兰素含量分别从74.0 μg/kg和259.0 μg/kg升高到636.1 μg/kg和1 284.0 μg/kg；压榨法成品菜籽油中香兰素含量范围为55.0～560.3 μg/kg，浸出法成品菜籽油中香兰素含量范围为0～370.5 μg/kg。综上，菜籽油中含有内源性香兰素，其主要来源于种植和加工阶段，含量随着加工过程而变化。 Aiming to clear the sources of vanillin in rapeseed oil and the background level of vanillin in rapeseed oil produced by different processes, and provide theoretical support for market supervision, firstly, a comparative analysis was conducted on the content of vanillin in rape straw, rape fruit pods, and rapeseed from different planting areas. Then, the changes in vanillin content in various processes of extracting rapeseed oil by pressing method were investigated, and the effects of frying temperature and frying time on vanillin content in rapeseed were further analyzed. Finally, the vanillin content in rapeseed oil produced by different processes was determined. The results showed that the contents of vanillin in rape straw, rape fruit pods and rapeseed varied greatly from different planting areas, and from the viewpoint of different parts of rape growth, vanillin content in rape straw was the highest, followed by rape fruit pods, rapeseed had the lowest vanillin content. In the process of extracting rapeseed oil by pressing method, the vanillin content in rapeseed increased significantly after cooking. The vanillin content in crude rapeseed oil was lower than that in prepressed cake. With the increase of refining degree, the vanillin content in rapeseed oil gradually decreased. With the prolongation of frying time and the increase of frying temperature, the vanillin content in rapeseed increased, and after frying for 50 min at 160 ℃, the vanillin content in rapeseed from Anqing, Anhui and Hailar, Inner Mongolia increased from 74.0 μg/kg and 259.0 μg/kg to 636.1 μg/kg and 1 284.0 μg/kg, respectively. The vanillin content in finished rapeseed oil produced by pressing method was 55.0-560.3 μg/kg, and the vanillin content in finished rapeseed oil produced by leaching method was 0-370.5 μg/kg. In conclusion, rapeseed oil contains natural vanillin, mainly comes from the planting and processing stages, and its content varies with the processing.