Chemical composition of hulled, dehulled and naked oat grains

Abstract

The objective of the work was to evaluate the influence of genetic and mechanical removal of hulls from oat grains on their nutrient content. The studies included three cultivars and six lines of oat grains. In grain samples of hulled (5 samples), dehulled (5 samples) and naked (4 samples) oats, the following components were determined: chemical composition (ash, crude protein, crude fat, crude fibre and its components) and amino acids and fatty acid composition. The grain of naked and dehulled oats contained significantly more crude protein, crude fat and polyunsaturated fatty acids, and considerably less saturated fatty acids and crude fibre than hulled oats. In addition, the dietary fibre composition was more favourable than the naked oats. The coefficients of nutritional values of the protein (total essential amino acids, essential amino acid index and amino acids score) of naked oats were higher than hulled and dehulled oats. In all the tested oat grain samples, lysine was the most limiting amino acid. The study showed that genetic and mechanical reduction of the proportion of hulls in oat grains resulted in a significant decrease in dietary fibre content and a significant increase in nutrient content.

Keywords: Hulled and dehulled oat grains; naked oat grains; chemical composition