Maltose

∞ generated and posted on 2023.05.17 ∞

Disaccharide consisting of two glucose moieties.

Maltose is also known as malt sugar because it is generated as an energy source in the seeds of grains such as those of barley, from starch, where ultimately it is used as a source of glucose The resulting malt sugar is then available for brewing malt-based beverages such as beer.

The sugar maltose is a product of starch digestion. Note that the bond linking together the two glucose moieties in maltose is an alpha (α) 1,4 glycosidic linkage just as one sees in the starch amylose as well as makes up most of the branched starches, amylopectin and glycogen.

Figure legend: Dehydration synthesis of maltose, a disaccharide, from two glucose molecules. Note the glycosidic linkage found between the two glucose moieties (lower, middle, immediately above the water molecule). Maltose, though, is predominantly generated from the breakdown of starch rather than synthesized directly from glucose. See too the hydrolysis of maltose to glucose, the upward-facing reaction, as is achieved during maltose digestion.

The above video is a remarkably good science-based introduction to why we call maltose 'maltose'.