The influence of the fortification of red pitaya ( Hylocereus polyrhizus ) powder on the in vitro digestion, physical parameters, nutritional profile, polyphenols and antioxidant activity in the oat‐wheat bread

Abstract This study evaluated the physical parameters, polyphenol profile and antioxidant activity before and after the in vitro digestion of red pitaya powder‐enriched oat‐wheat bread compared to plain wheat bread, oat‐wheat bread and red pitaya powder. The enrichment of red pitaya powder significantly increased the polyphenol, mineral contents, insoluble dietary fibre, firmness and moisture content of oat‐wheat bread compared to wheat bread, while contributed to a minor reduction in bread volume and dough extensibility due to gluten dilution. The oat‐wheat bread was found to have the lowest predicted glycaemic response, but 5%, 10% and 15% red pitaya powder formulated oat‐wheat bread showed a significantly lower glycaemic response than plain wheat bread as well as red pitaya powder.