Black Barley Grain and Its Processing By-Product as a Potential Raw Material for Functional Food

Barley husk, a by-product of the production of groats, is commonly regarded as a waste product, although it possesses high nutritional value. The present study sought to examine the health-promoting compounds, including insoluble and soluble fibre, vitamin B group, macronutrients and micronutrients, polyphenols, phytomelanin, and the antioxidant properties of both husk and dehusked black barley grain (H. v. var. rimpaui), in comparison with common barley (H. vulgare). Furthermore, the composition of two fractions of the husk (5% and 10% of grain weight) derived from H. v. rimpaui from both organic and conventional farming systems, as well as grains devoid of both of those layers, was evaluated. The study revealed that the alternative barley genotype exhibited a heightened propensity to concentrate higher amounts of the majority of the analysed components within its husk and grain in comparison to common barley. Regardless of genotype, the husk was identified as the richest source of the majority of studied bioactive components. The concentration of a specific compound was found to vary according to the particular husk fraction as well as the farming system, with a general tendency for greater concentration in organic raw materials. The findings suggest that the husk, a by-product of groat production, has the potential to serve as a raw material for functional food, particularly when derived from organic grains. Of the various barley forms, H. v. rimpaui might be considered especially suitable for this purpose, offering both high nutritional value and the enhancement of crop biodiversity.