Spring barley malt quality in eastern Washington and northern Idaho.

Malted barley (Hordeum vulgare L.) is a foundational ingredient for the brewing industry, providing functionality and flavor. Increasing demand for locally produced barley, supported by the craft brewing and malting industries, necessitates identifying environments and varieties to meet this demand. Therefore, we analyzed malt quality and quantified quality scores for adjunct (AQS) and all‐malt (AMQS) brewing for 12 barley genotypes grown at 11 locations in eastern Washington and Northern Idaho in 2017 and 2018. Genotype‐by‐environment interactions were identified for six out of nine of the malt quality traits. These included kernel plumpness, malt extract, diastatic power, α‐amylase, β‐glucan, and free amino nitrogen. Stability indices, including Eberhart and Russell's deviation from regression, simultaneous selection index, and mean of the relative performance of genotypic values were quantified. We identified genotypes that had high stability and high AQS (LCS Genie, LCS Odyssey, 12WA 120.14, 12WA 120.23, and GemCraft) or AMQS (LCS Odyssey, LCS Genie, Palmer, 11WA 107.36, 11WA 107.58). Significant correlations between rainfall and barley protein (r = −0.22, p < 0.001), and between barley protein and seven out of eight of the other malt quality traits, reveal important relationships that may influence malt quality. This study may aid producers in variety selection, and provides a detailed malt quality analysis, evidence of G×E interactions, and stability measures for barley genotypes within a production region that has the potential to meet malting barley demand. Core Ideas: Protein content had significant correlations with seven out of eight of the malt quality traits.Genotype × environment interactions influenced six out of nine of the malt quality traits.We recommend Genie and Odyssey based on malt quality scores and stability. [ABSTRACT FROM AUTHOR]