Spectrophotometric Determination of Vicinal Diketones and Their Precursors in Beer

This study was done to develop a spectrophotometric method for determining vicinal diketones and their precursors (total VDK), which would produce results comparable with those obtained using a gas chromatographic method. Recommended ASBC methods for determining diacetyl and reports on the topic in ASBC publications in the last five years were critically examined. All the procedures include sequential steps for sample treatment, separation, detection, and quantitative determination. The procedure and resulting sensitivity, reproducibility, and recovery of a modified total VDK ultraviolet micro method, as well as some comparative analyses with gas chromatography are reported.