Submitted to: American Society of Brewing Chemists Newsletter
Publication Type: Abstract Only
Publication Acceptance Date: 8/1/2003
Publication Date: 8/1/2003
Citation: BARR, J.M., HENSON, C.A., MCNAMARA, H., SCHWARZ, P.B. PREGERMINATION IN THE 2002 MIDWESTERN BARLEY CROP: ASSESSMENT AND OCCURRENCE. BREWERS DIGEST. 2003. V. Abs. #. Interpretive Summary:
Technical Abstract: Rainfall received during harvest resulted in a substantial portion of the 2002 Midwestern barley crop exhibiting pregermination (preharvest sprouting). The fact that the incidence was the most wide spread in more than 20 years, has provided a unique opportunity to evaluate and compare methodology for the assessment of pregermination. Samples (N=151) were collected from farms and elevators in North Dakota and western Minnesota during harvest, as part of a survey of regional crop quality. Pearling showed that 40% of samples exhibited visual signs of sprouting (0.1-17.4%). There was a moderate association (r=0.66) between Stirring Number, as determined with the Rapid Visco Analyser (RVA), and % sprout determined by pearling. Pregermination was also assessed by staining with fluoreccin dibutyrate, determination of alpha-amylase levels and leakage of electrolytes from seeds during imbibition. The latter parameter is used extensively in determining viability of large-seeded legumes. As there is evidence to suggest that germinative energy of pregerminated samples deteriorates with storage, 72 hr germination was determined after harvest and again following several months of storage at room temperature. Initial germination of the samples was 70-100%.