Physicochemical and Antioxidant Properties of Wheat Bread Enriched with Hazelnuts and Walnuts

The aim of this study was to evaluate the effect of wheat bread enrichment using hazelnuts and walnuts (1%, 3%, 6%, 9%) on the nutritional value and selected physicochemical and antioxidant properties. The dough and bread yield, volume, specific volume and porosity were also determined. The crumb texture was analyzed by texture profile analysis (TPA) test using a texture meter. The color of the crumb was assessed in the CIE L*a*b* color space. Antioxidant properties were determined by the ABTS(+) radical method. The contents of phenolic acids, flavonoids and total polyphenols were also determined. The test demonstrated that the enrichment of bread with nuts increased the level of minerals, protein, fiber and fat. Breads containing walnuts were characterized by the highest content of these nutrients. The bread with a 9% walnut content by the smallest volume (380 cm(3)) had lowest value of L*. The crumb of the enriched breads was characterized by greater hardness, gumminess and chewiness, the values of these parameters generally increasing in parallel to the nut content. Breads enriched with walnuts were characterized by a higher average total content of polyphenols (35.77 mg gallic acid equivalent (GAE)/100 g dry mass (DM)) compared to the breads enriched with walnuts (25.35 mg GAE/100 g DM).