Malt is a raw material for beer production, and malt milling is a key step in brewing beer. There are three types of malt milling: dry milling, humidifying milling and wet milling.
Moisturizing and milling is to humidify the malt with water or steam before crushing, so as to increase the moisture of the barley skin and increase its flexibility. It can be broken and not broken when crushed. Wet pulverization is to soak the malt in warm water at 30 ℃ ～ 50 ℃ for 15-30min before milling, so that the water content of the malt is increased to about 30%, and its volume expands by 35% -40% due to water absorption. Compared with dry milling, the advantages of humidifying milling and wet milling are as follows:
(1) Humidifying and wet milling can improve the filtration efficiency. Compared with dry crushing, the humidified and wet crushed malt hulls are kept intact, the filter layer is loose, and the filtering efficiency is improved. Humidification and crushing can increase the filtration efficiency by about 20%, and the filtration efficiency of wet crushing can be increased by more than 50%
(2) For the malt with poor solubility, the leaching rate of moisturizing and wet milling is higher than that of dry milling;
(3) Humidifying and wet milling can directly use fresh malt, while dry crushing must store the malt for a period of time to regain moisture;
(4) Humidification milling reduces dust flying, wet milling can completely solve the problem of dust pollution in malt milling.