Mash ingredients,
mash bill, or
grain bill are those materials used in
brewing from which a
wort can be obtained for
fermenting into alcohol.
Mashing is the act of creating and extracting
fermentable and non-fermentable
sugars and flavor components from
grain by steeping it in hot water, and then allowing it to rest at specific temperature ranges in order to activate naturally-occurring enzymes in the grain that convert the starches to sugars. The sugars will be separated from the mash ingredients and then converted to alcohol and other fermentation products by yeast in the brewing process.