When starch is hydrolyzed either by acid or by the enzymes maltase or diastase, contained in germinating barley, a yield of 80% of maltose is obtained. Maltose is built of two molecules of ${alpha}$-glucose, bound in the position 1:4 i.e., carbon atom 1 of one glucose molecule is bound in a glucosidic bond to carbon atom 4 of the second molecule. Until around 1960, dextrose and glucose syrups were prepared from starch exclusively by acid hydrolysis. The process was corrosive, and the dextrose yield low. It was, therefore, a great step forward when pure glucoamylase in combination with bacterial ${alpha}$-amylase made possible a complete enzymatic hydrolysis of starch to dextrose. Today several enzymatic processes are used in the industry.