The invention discloses a method for quickly analyzing total
diketone content of a beer semi-finished product. The method comprises the following steps: 1) preparing certain concentration of
peroxide solution; 2) adding certain volume and certain concentration of
peroxide solution to a sample before
distillation; 3) distilling the sample for about 6 minutes to finish
distillation by adopting a
direct heating and distilling mode; 4) adding certain volume and certain concentration of
hydrochloric acid solution to a 25ml distillate collecting
volumetric flask before
distillation, wherein the PH when the distillate is metered to the
full scale is about 1.2, so that the
diketone completely reacts with o-phenylenediamine to generate 2,3-dimethyl
quinoxaline; and 5) carrying out colorimetric determination by using a spectrophotometer, and calculating the total
diketone content. The quick
analysis method disclosed by the invention has the advantages of being quick, simple to operate, convenient, accurate, high in sensitivity and the like, the variable coefficients of the
repeatability and the reproducibility are smaller than 5% respectively, the
recovery rate achieves over 80%, the analysis time is shortened to 30 minutes from 120 minutes in an
electron beam curing (EBC) method, and the detection efficiency is improved by three times in comparison with that of the EBC method.