火焰原子吸收光谱法测定7种乳制品中微量元素及乳酸的含量

目的:测定7种乳制品中6种微量元素及乳酸的含量,证明乳制品中含有丰富的营养物质.方法:首先对7种乳制品进行消化:(1)采用火焰原子吸收光谱法对处理后的乳制品样品溶液中的Ca、Fe、Zn、Mg、Mn、Cu 6种无机元素进行直接定量分析测定;(2) 间接测定法测定乳酸含量.取一定量的消化后的乳制品样品溶液,使其与FePO4悬浮液作用,再用火焰原子吸收分光光度法直接测定Fe的含量,从而得出乳酸的含量.此种方法简单,精密度和灵敏度高.结果:7种乳制品中,Ca、Cu、Fe、Mn、Zn及乳酸含量相对较为丰富.结论: 乳制品中含有丰富的人体所必需的微量元素,同时乳酸含量也很丰富,长期饮用乳制品不但可以补充人体对微量元素的需求,而且乳制品中的乳酸也有助于人体消化吸收.因此,长期饮用乳制品有利于人体健康.

Determination of trace elements and lactic acid in the 7 kinds of dairy products by FAAS

Objective: To determine 6 kinds of trace elements and lactic acid in 7 kinds of dairy prod-ucts to show rich nutrition in the dairy products.Methods : Seven kinds of dairy products were digested.Then the followings were performed:(1) The six inorganic elements of Ca,Fe,Zn,Mg,Mn and Cu inthe dairy product solution were directly determined by Flame Atom Absorbability Spectrum(FAAS).(2)Indirect determination of lactic acid in dairy products by FAAS.Certain amount of the digested solutionwas mixed into FePO4suspension so that Fe could be determined by FAAS,and then lactate was deter-mined.Result: The seven kind of dairy products had more trace elements such as Ca,Fe,Zn,etc.andlactic acid.Conclusion: There were rich essential trace elements and lactic acid in the dairy products.Drinking a bottle of dairy product daily can supply trace elements to body,and lactic acid is helpful to di-gestion,so beneficial to health.