香菇中二氧化硫检测方法的探索与改进

Exploration and Improvement of Detection Method of Sulfur Dioxide in Mushrooms

目前香菇中二氧化硫的检测方法为GB5009.34-2016[1],但在实际工作中发现,由于香菇中存在有挥发性物质,在蒸馏过程中挥发性物质随二氧化硫一起被蒸发出来,从而造成检测结果偏高。本文采用全自动凯氏定氮仪进行蒸馏,由于蒸馏方式与蒸馏时间的改变,使得蒸馏结果更接近真实值,同时对比充氮蒸馏法,发现二者并无区别,说明凯氏定氮法可应用于香菇中二氧化硫的测定。

At persent, the detectiong method of sulfur dioxide in Mushrooms is GB5009.34-2016[1]. However, in practice, it was found that the volatile substances in Mushrooms were evaporated with sulfur dioxide in the distillation process, which resulted in higher detection results. In this paper, Kjeldahl nitrogen analyzer is used for distillation. Because of the change of distillation mode and distillation time, the results of distillation are closer to the true value. At the same time, compared with the nitrogen-filled distillation method, it is found that there is no difference between the two methods. It shows that Kjeldahl nitrogen determination method can be applied to the determination of sulfur dioxide in Mushrooms.