The influence of steep regime and germination period on the malting properties of some hull-less barley lines

Following field trials in 2008 and 2010, six lines, derived by mutation in the hull-less barley cultivar Penthouse, were selected to provide a range in grain beta-glucan content. These lines, along with Penthouse and the hulled, malting variety Optic, were then malted, using four different steeping regimes, with samples kilned after 3, 4 and 5 days of germination. The longest steep regime provided samples with optimum modification after 5 days of germination. Samples from the other steep regimes were under-modified to varying degrees. In particular, the steeps with a single immersion gave poorly modified samples with low extracts and alcohol yields. One line, with low grain beta-glucan, gave higher alcohol yields than either Penthouse or Optic, following a regime comprising two short immersions and a single air-rest, but there was no clear association, within the lines, between beta-glucan content and malting properties. Copyright (c) 2012 The Institute of Brewing & Distilling