ROLE OF FERMENTATION CONDITIONS ON FLAVOR STABILITY OF BEER

To clarify the role of wort fermentation conditions on the stability of the resulting beer, the flavor stability of beers brewed at several fermentation temperatures (6-30-degrees-C) in a pilot brewing plant (30 l) was studied using chemiluminescence analysis. Chemiluminescence (CL) production in fresh and stored beers increased with fermentation temperatures. Flavor stability of the beers increased with decreasing fermentation temperatures. Sulfite content in the fresh beer decreased with an increase in fermentation temperatures. When sulfite was added to beer, the CL production in beers before and after storage decreased and the flavor stability increased with the concentration of sulfite. These data showed that it was an advantage for beer flavor stability to increase the sulfite level during fermentation. In this pilot study, the CL producing activity had a negative relationship with sulfite content in beer and with flavor stability, indicating that the CL producing pattern of beer is a useful indicator for the evaluation of beer stability in the development of a more stable beer.