Mash is a mixture created by combining grains, such as barley or corn, with hot water. This process helps to break down the starches in the grains into sugars, which are essential for fermentation. The resulting mash is a thick, porridge-like substance that is a key step in making beverages like beer and whiskey. After the mash is prepared, it undergoes a process called fermentation, where yeast is added to convert the sugars into alcohol. This transformation is crucial for producing the final product. The quality of the mash can significantly influence the flavor and character of the finished alcoholic beverage.