A Reappraisal of the Differences Between Scandinavian and Spanish Barleys: Effect of β-Glucan Content and Degradation on Malt Extract Yield in the cv. Scarlett

Abstract

Forty one samples of the malting barley cultivar Scarlett were collected from both Scandinavia (15 from Finland and 10 from Denmark) and the iberian Peninsula (15 from Spain and 1 from Portugal), during the harvest years of 1998 and 1999. These samples were subjected to grain analyses, comprising protein content, hordein fractions by high performance liquid chromatography (HPLC) and β-glucan content. The samples were micro-malted and the malts were analysed to determine different patterns in the influence of grain composition on malt extract development linked to the two contrasting environments. The most obvious difference found between the Scandinavian and Iberian barleys was the effect of the total and insoluble barley β-glucans. They were an effective barrier of malt extract in the North, but appeared to increase extract in the South. A conclusion was that the positive effect of β-glucans in the Iberian barleys was a consequence of their greater capacity to synthesise and release β-glucan hydrolases during germination.