Usage varies. 1tsp. Breaks 1,4 linkage in starch during liquefication, producing dextrin and a small amount of maltose.
Can increase fermentability of high gravity extract worts. Also typically used to convert high adjunct mashes such as full cracked corn mash.
Leaves 1,6 links, therefore self-limiting. Use if you have a starch problem in storage, or in light beers