<Tr> <Th> PubMed </Th> <Td> articles </Td> </Tr> <Tr> <Th> NCBI </Th> <Td> proteins </Td> </Tr> <P> γ - Amylase (EC 3.2. 1.3) (alternative names: Glucan 1, 4 - α - glucosidase; amyloglucosidase; Exo - 1, 4 - α - glucosidase; glucoamylase; lysosomal α - glucosidase; 1, 4 - α - D - glucan glucohydrolase) will cleave α (1--6) glycosidic linkages, as well as the last α (1--4) glycosidic linkages at the nonreducing end of amylose and amylopectin, yielding glucose . The γ - amylase has most acidic optimum pH of all amylases because it is most active around pH 3 . </P> <P> Alpha and beta amylases are important in brewing beer and liquor made from sugars derived from starch . In fermentation, yeast ingest sugars and excrete alcohol . In beer and some liquors, the sugars present at the beginning of fermentation have been produced by "mashing" grains or other starch sources (such as potatoes). In traditional beer brewing, malted barley is mixed with hot water to create a "mash," which is held at a given temperature to allow the amylases in the malted grain to convert the barley's starch into sugars . Different temperatures optimize the activity of alpha or beta amylase, resulting in different mixtures of fermentable and unfermentable sugars . In selecting mash temperature and grain - to - water ratio, a brewer can change the alcohol content, mouthfeel, aroma, and flavor of the finished beer . </P>

Which type of amylase will cleave both α-1 4 and α-1 6 glycosidic bonds