Use of barley with black hulless grain in human nutrition

The different colour (black or purple) of cover layers of cereal grain is often linked with the differentiated content of polyphenolic compounds, i.e. phytonutrients that contribute to a high antioxidant pool of the barley grain for human nutrition. In 2004-2006, the highest-yielding hulless barley materials with black grain from the World Collection of Spring Barley Genetic Resources maintained at Kromeriz (Czech Republic) were studied in comparison with the hulled malting cultivars Jersey and Tolar, and a new breeding line of hulless barley KM1910 with light grain. The significant differences were found in both the grain basic composition (the content of N-substances and starch) and basic malt and wort parameters (particularly the beta-glucan content of wort, friability, final attenuation of wort, extract content, Kolbach index, colour of malt), and the content of chosen polyphenolic compounds (the total content of polyphenols, anthocyanogenes and flavanoids) between the hulled cultivars and hulless materials as well as within hulless barleys. The black barleys produced high beta-glucan content (1034-1998 mg.l(-1) in the wort, i.e. as much as fivefold higher than that in cvs. Jersey and Tolar), however, the highest content of all polyphenolic coumpounds and especially flavanoids was assessed in the hulless line KM1910 with light grain (max.=14.32 mg.l(-1), i.e. ca. 177% of the total mean). The possibilities of different use of these barleys in production of health-supporting foods as well as commercial bakery products are discussed.