Arpa Unu ve Çavdar Unu İlavesinin Buğday Unlarının Bazı Fiziksel, Kimyasal, Reolojik ve Ekmek Kalite Özellikleri Üzerine Etkisi

Abstract

The aim of this study was to investigate dough rheological properties and bread quality characteristics of wheat flour supplemented with hulless barley and rye flours at different ratios. Hulless barley and rye flours were added to wheat flour at the levels of 10, 20, 30, 40, 50%. Chemical (protein, ash), physicochemical (wet and dry gluten, gluten index, Zeleny sedimentation) and rheological (Farinograph, Mixolab) characteristics of the prepared flour mixtures were determined. The quality characteristics of breads (weight, loaf volume, sensory properties, color and texture) produced from the flour mixtures were also investigated. β-glucan contents of hulless barley flour and the breads produced from the hulless barleywheat flour mixtures were also analyzed. The ash content of the wheat flour was in agreement with Turkish Food Codex. Protein content and Zeleny sedimentation value were higher than the minimum values indicated in the codex. The gluten quality of wheat flour (as indicated by Zeleny sedimentation value and gluten index) was suitable for producing bread with good quality, but its amylase activity was relatively low. The Farinograph stability and dough development time values of the sample supplemented with 10% rye flour were higher than the control sample. Further increases in the rye flour supplementation level caused decreases in stability, dough development time and water absorption values but increases in softening degree as compared to the control sample. The Farinograph stability and dough development time values of the samples supplemented with hulless barley flour were lower than the control sample, but their water absorption values were higher than the control. The Mixolab stability, dough development time ( C1: minute), and water absorption values of the rye flour-wheat flour mixtures decreased as the rye flour supplementation level was increased as compared to the control sample. The Mixolab stability and dough development time ( C1: minute) values of the hulless barley flour-wheat flour mixtures decreased, but the water absorption increased as

ix compared to the control sample, as the hulless barley flour supplementation level was increased. The loaf volume values of the samples supplemented with rye flour increased up to 40% supplementation level and the increase was significant at 30% supplementation level. The loaf volume values of the sample supplemented with 10% hulless barley flour slightly increased but the increase was not significant and further increases in hulless barley supplementation levels caused decreases in loaf volumes but the decrease was significant at supplementation level of 30% and above. The texture analysis results of the bread indicated that rye flour supplementation caused a significant decrease in crumb hardness at 10 and 20% rye flour supplementation levels. On the other hand hulless barley supplementation caused a significant decrease in crumb hardness at 40 and 50% hulless barley flour supplementation levels. β-glucan contents of the hulless barley flour supplemented breads increased as the hulless barley supplementation level was increased.