Evaluation of the effects of fortification with hulles barley and oat on some nutritional and product properties of bread

In this study, the effects of enriching bread wheat flour with hulless barley and oat whole grain flour on some nutritional and product properties were investigated. For this purpose, in the study, the flours of Yazır hulless oat and Yalın hulless barley varieties were substituted into commercial bread flour at the rates of 0, 25, 50, 75, and 100%. Some technological quality properties of substitute flours and technological, nutritional, and product properties of breads obtained from substitute flours have been revealed. In the study, as the additive rate of hulless whole grain barley and oat flour increased, gluten quality properties weakened; β-glucan, protein, and total phenolic contents increased; and total antioxidant activity values increased. The hulless barley flour substitution had a more positive effect on the amount of β-glucan. In the breads, as the substitution rate increased, the ash content (1,754-2,669%), the protein content (10,38-16,36%), the β-glucan content (0,36-4,32%), the total phenolic content (82,2-200,1 mg GAE/100 g), the total antioxidant activity (192,1-424,3 µmol TE/g), the mineral content increased, and bread volume values decreased. The volumes of bread substituted with hulless barley varied between 237,5 and 397,5 ml, and the volumes of bread substituted with hulless oats varied between 283,5 and 425,0 ml. The volume of hulless oat flour breads was found to be higher at all substitution rates. As the substitution rate increased, the a* and b* values in the bread crust decreased, while the L* value in the bread decreased and the a* value increased. A significant increase in hardness was observed in both hulless oat and hulless barley-substituted breads after a 25% substitution rate. The Fe, K, and Zn content of bread substituted with hulless barley and the Ca, Cu, Mg, Mn, P, and S contents of bread substituted with hulless oats were found to be high. It was determined that the recommended 3 g β-glucan requirement was met by consuming bread with a 75% replacement rate, and this value was approached with a 50% replacement rate. It has been observed that this requirement can be met in breads with a 50% hulless barley substitute. The sensory scores of breads with a 25% substitution ratio of both flours were close to control, and breads with a 50% substitution ratio received acceptable sensory scores. As a result of the study, the addition of hulled oats had a more positive effect on the processing properties, while the addition of hulless barley had a more significant effect on improving the nutritional properties of bread.