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目的 通过对酚试剂法测定豆芽中甲醛的两种前处理方法进行比较,探讨测定豆芽中甲醛的方法.方法 分别以直接浸泡法和水蒸气蒸馏法作为前处理方法,利用甲醛与酚试剂反应,在波长645 nm处测量吸光度,进行定量分析.结果 直接浸泡法和水蒸气蒸馏法作为前处理方法测定的标准偏差分别为1.6％～2.3％和1.7％～2.6％,浸泡提取法重现性更好;回收率范围分别为80.1％ ～92.4％和80.4％～97.4％,水蒸汽蒸馏法回收率结果略高.结论 在固定检测方法的条件下,可根据实验室所具备的仪器条件,选择合适的前处理方法进行样品检测.“,”Objective To compare two pretreatment methods in determination of formaldehyde in bean sprouts by using phenol reagent spectrophotometry.Methods Direct immersion method and water vapor distillation method were used as pretreatment methods respectively,the absorbance of reaction of formaldehyde and phenol reagent was detected by spectrophotometry at 645 nm.Results RSDs were 1.6％-2.3％和 1.7％-2.6％ for the direct immersion method and water vapor distillation method,the latter had better reproducibility.The recovery rates were 80.1％-92.4％和 80.4％-97.4％ for above two methods,water vapor distillation was higher.Conclusion Under the fixed detection condition,the suitable pretreatment method for bean sprouts can be selected according to the instrument condition in the laboratory.