Brewing is the process of making alcoholic beverages – generally beer, but also sake and pulque – from starchy cereal grains. Brewing has been practiced for more than 5,000 years. The cereal (generally barley) is malted (steeped in moisture and germinated). The malt is then dried, cured at 100°C, and mashed – ground and infused with hot water; in mashing the enzymes produced during malting break down the starch to fermentable sugars. The wort (aqueous solution) is filtered and boiled with hops, and then fermented in large vessels with yeast and fermentation. When this has almost ceased, the beer is run off and stored to mature; finally, it is filtered, carbon dioxide is added, and the beer is packaged. The strain of yeast used helps to determine the type of beer made.