Physicochemical properties and antioxidant activity of gluten-free riceberry-cheese cracker under simulated gastrointestinal transit

Abstract

This study aimed to develop a gluten-free cracker by substituting wheat flour (WF) with riceberry flour (RB) combined with cheese’s milk proteins to replace gluten. The effect of substitution of WF with RB at 50 and 100% (RB50 and RB100, respectively) on cracker properties were evaluated. The results showed that water activity, hunter colour value (L*), hardness, and thickness decreased with an increase in the RB content. This related to a compact structure and a weaker crystallinity of RB cracker when compared with WF-based cracker. The substitution of WF with RB50 and RB100 in cracker significantly (P < 0.05)increased the phytochemical content resulting in increased antioxidant properties.The synergistic effect of the bioactive compound of RB and the bioactive peptides originating from cheese's milk proteins on antioxidant capacity was observed under simulated GI digestion. The greatest increase in the ABTS•+ radical scavenging activity and reducing power was observed in the RB100 cracker at the intestinal digestive phase with the values of 15.74 ± 0.27 and 3.70 ± 0.06 mg Trolox eq./g sample, respectively. The results suggest that the substituted 100% RB combined with cheese’s milk proteins have a potentiality to be developed into a novel gluten-free product with enhanced antioxidant properties.