3种测定乳制品中乳糖含量方法的比较

Comparison between three methods of detecting the lactose content in dairy products

为确定一种快速、简易、灵敏的测定乳糖的方法,比较了直接滴定法、蒽酮法和碘量法3种方法测定乳制品中乳糖含量的差异。结果表明:平行试验直接滴定法精度最低,但其乳糖回收率的最大相对误差最小;蒽酮法精度高,但其乳糖回收率的最大相对误差最大,而且蒽酮试剂腐蚀性强,操作不安全;碘量法的精度与乳糖回收率的最大相对误差均介于直接滴定与蒽酮比色法之间,综合而言,碘量法的重复操作性强,结果准确,测定乳制品中乳糖含量可优选碘量法。

To determine a fast,simple and sensitive method for the determination of lactose,the differences were compared among the direct titration method,anthrone method and iodometric method for detecting the lactose content in dairy products.The results showed that the maximum relative error of lactose recovery test by the direct titration and its accuracy of parallel test were minimum.The anthrone method＇s relatively error is largest at high precision.But the anthrone reagent is corrosive and unfit for operation.The precision and the maximum relative errors of lactose recovery of iodometric method are between the titration and anthrone colorimetric method.In conclusion,iodometric method is accurate,repeating and operable.So,iodometric may be the prior choosing method for the lactose content test in dairy products.