Characterization of Prickly Pear Peel Flour as a Bioactive and Functional Ingredient in Bread Preparation

The aim of the present research was to evaluate the addition of prickly pear peel flour (PPPF) to bread dough as a source of nutrient and bioactive compounds. The PPPF's physical, chemical and nutritional composition was evaluated, as well as its content of bioactive compounds betalains, and flavonoids. The characterization evidenced high fiber and carbohydrate contents and an elevated amount of polyphenols and betalain compounds. The PPPF was then added at different concentrations (5, 10, 15, 20, 50%, w/w) to bread formulations as a potential functional ingredient. All concentrations, except 50% PPPF, evidenced good leavening dough properties and were then tested for baking. In relation to the content of added PPPF, the amount of betalains, representing bioactive compounds, remained high even after the baking process, suggesting a protective matrix effect. Among the different formulations, those containing PPPF at 10% showed the highest values in terms of the leavening dough capacity and bread specific volume and received the best sensory evaluation score.

Keywords: Opuntia ficus indica; antioxidant activity; bread; food byproducts; functional ingredient; phenolic compounds.