Barley Starch Structure And Quality For Brewing Impacts Of Genotype Environment And Crop Management

Key malt processing quality parameters, like the starch gelatinization temperature, vary with barley variety and harvest year. More knowledge is required regarding the relative significance of genotype, environment and crop management practices in determining starch properties. This project will be conducted in partnership with AB InBev, the world's largest brewing company, who manufacture one in four of all beers consumed worldwide. There will be an opportunity to gain valuable industry experience during a placement within a Technical Division of AB InBev.
Barley starch comprises amylopectin, amylose, lipid, and water. The structure of amylose and amylopectin, and the proportion of amylose in granules is under genetic control and is subject to genotypic variation. Stressful environments, have a regulatory effect on the size of the starch granules, the amylose to amylopectin ratio and the amount of lipid within the barley starch. The aim of this project is to examine how starch functional properties are altered when the barley plants are subjected to different water amounts and timing during the growth phases. This is important because while growers, maltsters and brewers require grain yield stability and product uniformity this will be challenging in an era of variable weather patterns. Being able to predict the general physico-chemical nature of the starch in barley because of water stewardship is a step towards "Smart Agriculture" required for barley sustainability.
In Year 1, several lines will be grown across two distinct sites to generate samples for initial characterization, training in the required techniques and to provide an initial snapshot of the significance of genotype. In subsequent years selected varieties will be grown in multiple sites both within the UK and globally under controlled conditions selected to evaluate the separate impacts of environment and crop management practices.
Barley samples will be micromalted and characterized for significant parameters related to starch breakdown during mashing, including: nitrogen content, starch content, amylose to amylopectin ratio. Thermal properties of the starches will be determined using Differential Scanning Calorimetry (DSC) and Rapid Visco Analysis (RVA). Malts will be mashed using industry standard protocols and the resulting wort extract and fermentable sugars spectrum determined. Statistical analyses will determine the relative impacts of genotype, site and management practices on starch properties and function. Desirable traits and practices linked to best performance in brewing will be identified.