Alpha amino nitrogen and fusel alcohols of sorghum worts fermented into lager beer

The levels of alpha amino nitrogen (AAN) and fusel alcohols during fermentations of lager worts produced from waxy sorghum grits either inoculated with yeast cultured in wort or yeast-malt media were performed. Worts produced from waxy sorghum grits had comparable AAN to commercial wort. The oxygen concentration hi the reactor headspace changed from 20% at the beginning of fermentation to less than 1% after 72 hrs fermentation indicating a gradual change from aerobic to anaerobic conditions. The utilization of AAN for production of propanol, isobutanol mid amyl-isoamyl alcohols from waxy sorghum grits was comparable to a control wort. Production of propanol, isobutanol mid amyl-isoamyl alcohols followed the same trend over 144 hr fermentation Isobutanol was produced in the lowest concentration. The initiation of propanol production occurred after 24 mid 36 hr fermentation for worts inoculated with yeast cultured hi wort mid yeast-malt media, respectively. The finial concentration of ethanol and fusel alcohols were within the expected range found hi commercial beers. Worts produced from barley malt and waxy sorghum grits were an adequate substrate for Saccharomyces cerevisiae, and were comparable to a commercial wort. The utilisation of refined waxy sorghum grits as brewing adjuncts for lager beers was demonstrated.