AMYLASE ACTIVITY AND ENDOSPERM HARDNESS OF HIGH LYSINE BARLEYS

Abstract

Several of the high lysine barleys selected by the Udy dye binding method have altered proportions of the main protein fractions. These varieties also vary considerably in endosperm hardness measured as the amount of electrical energy required for milling. A few have endosperms requiring a higher milling energy than that of the parental variety, but five high lysine varieties have soft endosperms typical of barleys that malt readily. In addition the high lysine selections differ markedly in β-amylase and diastatic activity. Mutant R 1508 with the highest grain lysine has very low diastatic activity, whereas R 56 and Hiproly have diastatic activities equivalent to that of a known high diastase barley. α-Amylase activity of high lysine barleys also ranges widely and tends to be inversely related to diastatic activity.