Integrating Solutions at the Intersection of Climate Change and Flavor: Breeding for Sustainable Malting Barley and Beer Sensory Characteristics

The following thesis consists of four sections: a general introduction, two manuscripts, a general conclusion, and an overall bibliography. The two manuscripts report on: (1) discussing the prospects of developing a perennial malting barley and potential alternative sustainable crop management practices and (2) further exploring the contributions of barley variety to beer and hot steep flavor characteristics. The first manuscript discusses four possible paths to achieving the conversion from annual to perennial growth habit while maintaining expected levels of malting quality and agronomic performance: direct domestication, wide hybridization, manipulation of the vernalization and photoperiod sensitivity genes, and mapping annual and perennial forms of ryegrass (Lolium multiflorum L., and L. perenne. L, respectively) as a basis to identify genes conferring perenniality. The second manuscript used two independent sets of barley germplasm to address the contributions of other, different barley genotypes to beer flavor. Pedigree, malt quality, beer quality, sensory attributes, and metabolomic profiles were compared within and between the two sets. Differences in malt hot steep and lager beer sensory that are attributable to barley genotype, as assessed by laboratory research and/or consumer panels, were investigated, along with differences in abundance of metabolomic compounds. The observations within this study lead to the conclusion that the variable metabolites observed among the two sets of barley germplasms are a direct result of genetic differences that lead to differential responses within the malting and brewing processe

Genetic basis of barley contributions to beer flavor

13 Pags.- 1 Fig.- 3 Tabls. © 2022 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license.Barley malt is critical for the malting, brewing, and distilling industries, as it is one of the main ingredients of beer and some types of spirits. There is growing evidence that barley genotype - via malt - can impact the flavors of beers and spirits. However, information on the barley genes involved in these flavors is lacking. Therefore, we used quantitative trait locus (QTL) mapping of malt quality traits, beer sensory descriptors and metabolic compounds on a biparental population of doubled haploids derived from the cross of the cultivars Golden Promise and Full Pint. Putative candidate genes for QTLs were identified by alignment with the reference barley genome sequence. There were thirty-seven QTLs across all chromosomes except 4H, with three QTL clusters located on 3H (1 cluster) and 5H (2 clusters: mid-5H and end-5H). Those “hotspots” contained QTLs for multiple phenotypes. Several candidate genes that regulate plant metabolism were identified within the QTLs and included HvAlaAT, HvDep1, HvMKK3, HvGA20ox1 and HvGA20ox2. These genes are involved in seed dormancy and plant height. Alleles at these loci, and perhaps at physically linked loci, can have key downstream effects on malting quality, beer flavor, and abundance of volatile metabolites.Research at Oregon State University was supported by the Agricultural Research Foundation Barley Progress Fund. At Colorado State University, research was supported by CSU's College of Agricultural Sciences, with partial support from the American Malting Barley Association.Peer reviewe