Location: Cereal Crops Research
Project Number: 5090-30600-001-000-D
Project Type: In-House Appropriated
Start Date: May 13, 2025
End Date: May 12, 2030
Objective:
Objective 1: Explore the genetic basis of grain water sensitivity using contemporary and heirloom malting barley varieties.
Objective 2: Perform functional analysis of the HvMKK3 gene during preharvest sprouting and its impact on malting quality in barley.
Objective 3: Evaluate and report intrinsic malting quality parameters of commercially viable barley cultivars as part of a Congressionally directed mission of service (non-hypothesis driven).
Approach:
We routinely receive over 6,000 submissions annually from across the U.S. for which we prepare, malt, analyze for multiple quality parameters, and report results. A goal in the previous research project was to fortify malt processing equipment and staff to increase our processing numbers. Moving into this next project cycle, we will be working toward replacement of aging malting machines (steep tanks and germinators). Improvements in process and water use efficiency will be a priority within the new designs. Our processing and test procedures are generally based on the ASBC Methods of Analysis, with some slight modifications and improvements.
Since submissions are being compared within individual breeder’s experiments and to all other lines being malted, consistent treatment during malting and analysis is critical for reliable, reproducible results, and conclusions. Barley seeds of early generation breeding lines and experimental populations vary in size. As such, the duration of steeping is adjusted for the grain to reach the target of 45% moisture, as it significantly affects the malting quality results. Average steep time is calculated by determining the average kernel weight (mg), protein content (using NIR) and moisture content in the seeds (using NIR or a seed-moisture reader. Samples are germinated at 17ºC, at near 100% humidity, with intermittent rotation for three minutes every half-hour. At the end of steep, weight for each sample is noted and a final water adjustment to bring the samples to 45% moisture (on weight basis) is made if necessary. After 5 days of germination, the “green malt” is moved to the kiln and the samples are gently dried for 24 hours, starting with a temperature of 49ºC for 10 h, and rising to 85ºC for the last 3 hours.
Once the samples are steeped, malted, kilned, and cleaned (rootlets and emergent acrospires removed), they are stored for a minimum period to allow moisture equilibration and sample aging before analysis, as is standard practice in the industry. Malts are ground and mashed (ASBC Method: Malt-4) and analyzed for % extract (ASBC Method: Malt-4), soluble protein (ASBC Method: Wort-17), color and clarity (ASBC Method: Wort-9), free amino nitrogen content (ASBC Method: Wort-12) and beta-glucan levels (ASBC Method: Wort-18). Malt grist is extracted into salt water at 20ºC and the diastatic power (ASBC Method: Malt-6) and alpha-amylase activities (ASBC Method: Malt-7) are determined. Total nitrogen contents of the barley are determined using FOSS Nova NIT and malt are determined on a LECO Corp. FP828 Nitrogen Analyzer utilizing the Dumas total combustion method (ASBC Method: Malt-8).