Lyophilized Kale (Brassica oleracea L.) Leaves as an Enhancing Component in Gluten-Free Bread

Abstract The objective of the research was to assess the impact of powdered kale (Brassica oleracea L. var. acephala) on the properties of starchy gluten-free dough and bread. Kale lyophilisate was added to the recipe as 3%, 6%, or 9%, replacing the starch. The addition of the kale resulted in a decrease in the dough's strength despite the optimisation of the water content. The presence of kale lyophilisate reduced the volume of the loaves, in comparison with control, resulting in a decrease in crumb porosity and pore density, and an increase in the quantity of large pores. The addition of lyophilised kale at all levels resulted in an increase in taste acceptability, while the 6 and 9% kale decreased the acceptability of the other sensory parameters. The presence of the kale lyophilisate led to a reduction in crumb hardness on individual days of storage compared to the control sample, and the decrease was greater the more kale powder was added to the recipe. Bread with the highest concentration of the kale lyophilisate showed lower enthalpy of retrograded amylopectin decomposition in subsequent days of storage.