Chemical evaluation of beer flavor stability.

Kaneda, H., Kobayashi, N., Furusho, S., Sahara, H. and Koshino, S.

Abstract
The compounds responsible for the characteristic off flavour of stale beer are formed by the oxidation of certain beer constituents such as phenolic compounds and hop derived substances. It has been shown that the reactions which bring this about cause the emission of very low levels of chemiluminescence. Experiments are described in which it was demonstrated that the pattern of chemiluminescence emissions from fresh beer and beer stored at 37 degrees C for up to 5 days, together with the activity level in fresh beer of certain constituents (polyphenols, etc.) which reduce the 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical, can be used to predict the flavour stability of beer as determined by the intensity of staleness in beer tasted after storage.
Keywords : analysis beer chemiluminescence flavour off flavour oxidation prospect reduction stability staling