When unmalted cereals are used as barley substitutes the quantity of malt made from barley which is used may be diminished in beer to as low as 10 percent. The quality of the beer made partly from unmalted cereals is not equal to that made from pure malt. For the conversion of the starch in the unmalted cereals a mash is made by grinding the cereals, and this is treated with the quantity of malt necessary to convert the starch of the unmalted cereals into sugar. This is accomplished best at a temperature of from 90 to 100o. After the sugars are formed in this way the rest of the process in making beer is that just described.