A major sugar produced by digestion of starch in malting. a amylase releases maltotriose from starch chains by random hydrolysis. Maltotriose is fermentable by most brewing yeast but this depends on the health of the yeast. Old, stressed or continually repitched yeast may be less efficient at fermenting maltotriose and so leave the beer with an incomplete fermentation and an undesirably high final gravity.