啤酒中微量甲醛的光谱法测定

Determination of formaldehyde in beer by spectropotometry

目的:建立测定啤酒中微量甲醛的新方法。方法:在酸性条件下将溶解于啤酒中的游离甲醛随水蒸出,与乙酰丙酮作用,生成稳定的黄色化合物2,5-二乙酰基-1,4-二氢卢剔啶,在414nm处测吸光度,即可得到啤酒中甲醛含量。结果:测定微量甲醛的线性范围为0.0～2.4μg/ml,样品加标回收率98.4%～100.9%。结论:该法简便,灵敏度高,重现性好,适合啤酒中甲醛的测定。

Objective：In the acidity condition, free formaldehyde was distilled through the vapour. Methods：2,5 -diacetyl - 1,4 - dihydrophridine compound was synthsized from free formaldehyde and acetylacetone. Formaldehyde contents were obained throuth determining the absorbency of the compound （k = 414 nm）. Results：The linearity ranged from 0. 0 ～2.4 μg/ml. The rate of recovery of formaldehyde ranged from 98.4% ～ 100. 9% in the samples. Conclusion：The method is simple and sensitive. It adapts to determine formaldehyde contents in beer.