摘要
甲醛是一种常用的防腐剂。对人体有害,不允许在食品中存在。为检测食品中甲醛的含量,利用甲醛与乙酰丙酮生成稳定的黄色化合物.。在412 nm波长进行光度测定,其吸光度(A)与甲醛浓度呈线性关系,还原剂对测定结果有较强的负偏差影响,三价铁离子对测定结果有正偏差影响。光照使结果不稳定,三乙醇胺对显色有一定的增敏作用。
Formaldehyde in food sample was distilled and an aliquot of the distillate was treated with acetylacetone to form a stable yellow colored compound which has its absorption maxima at 412 nm. Linear relationship between the absorbance and concentration of formaldehyde was found in the range of 0. 60 to 225 μg of formaldehyde per 50 mL of solution. The presence of reductants in the test solution led to low results and the presence of Fe（Ⅲ） gave high results. Absorbance of the colored product kept stable in 30 min and should be protected from light. Addition of an appropriate amount of trihydroxyethylamine （TEA） gave a slight sensitizing effect.
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
2005年第10期755-756,共2页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
关键词
光度法
甲醛
乙酰丙酮
食品
Photometry
Formaldehyde
Acetylacetone
Foodstuff
