甲醇的定量方法甚多,习用者有品红亚硫酸(Schiffs试剂)法和变色酸(铬变酸Chromotropicacid)法,这些已为某些国家药典所选定,其中品红亚硫酸法尤为常用,并有较长的应用历史。两法的共同点系采用Deniges氧化法将甲醇氧化成甲醛后加入显色剂进行比色测定。它们均受氧化时间、显色时间、温度、乙醇含量等条件的影响。近年来,关于品红亚硫酸法,曾有过许多试验报告,如杨、李氏证明了有乙醇存在时,乙醇含量对测定有影响,过量乙醇存在使甲醇不能显色。刘、汪氏证实了如有过量的硫酸存在可便乙醛和其它醛类与品红加成物褪色,除去干扰(本文作者据从多数饮料样品检验 There are many ways to quantify the amount of methanol. There are two methods for determining the amount of methanol, such as the Schiffs reagent method and Chromotropic acid method. These methods have been selected by the pharmacopoeia of some countries. Magenta sulfite method is most commonly used, And a longer history of applications. The common ground between the two methods is to use the Deniges oxidation method to oxidize methanol to formaldehyde and then add a color reagent for colorimetric determination. They are affected by the oxidation time, color time, temperature, ethanol content and other conditions. In recent years, on the malachite sulfite method, there have been many test reports, such as Yang, Lee proved the presence of ethanol, the ethanol content has an impact on the determination, the presence of excessive ethanol methanol can not color. Liu, Wang confirmed that in the presence of excess sulfuric acid acetaldehyde and other aldehydes and magenta adducts fade, remove the interference (the author of this test from most drinks