Influence Of Thermal Load On Flavor Of Beer

The reason for the off-flavor of "caramel", "burnt" or "stale" in many Chinese beer brands is mainly due to the trouble on the hot-side in beer production. Decreasing of the thermal load may not only of the decrease of energy in production but also the key technology in brewing of the light-type beer.In this study, the influences of heat load on the main flavor compounds of beer are investigated in beer production of malting, mashing, rice cooking, sterilization and storage. Some of the theories of saving energy and improving flavor quality discussed in this paper will be helpful to Chinese breweries.The major results are summarized as follows.(i) The heat indexes such as TBN and 5-hydroxy methyl furfural are influenced by thermal load of beer production of malting, mashing, rice cooking, sterilization and storage. On the whole system of beer brewing, mashing and storage may have effects on beer flavor while malting, rice cooking and sterilization may have no effects.(ii) The wort and beer produced by a new mashing technology which decreasing the heat load have no "burnt" off-flavor and thus better flavor stability.(iii) The effects of storage temperature on flavor stability of beer are studied by means of natural and forced aging, and it was proved that the TBN, 5-hydroxy methyl furfural and color were increased with the temperature. The diacetyl increased and the esters like ethyl acetate and isoamyl acetate decreased which may caused "diacetyl" off-flavor and decreased "ester" during beer storage.