Effect of maize germ protein hydrolysate addition on digestion, in vitro antioxidant activity and quality characteristics of bread

This study investigated the fortification of bread with 1, 2, and 4 g/100 g of maize germ protein hydrolysate (MGPH) for enhancement of in vitro antioxidant potential of the bread before and after digestion and α-amylase inhibition during digestion. Furthermore, color, moisture content and texture profile of the fortified bread were assessed. Hydrolysate addition at 4 g/100 g increased DPPH˙ scavenging activity and Fe2+ chelating activity of the bread ~2.3 and 2.1 times compared to control, respectively. After simulated digestion, DPPH˙ scavenging activity increased ~4 time while the Fe2+ chelating activity decreased significantly (p < 0.05). The starch digestion rate decreased with increasing MGPH concentration, especially in the first 20 min of in vitro digestion. MGPH improved the bread texture during storage with reductions in hardness and chewiness. Sensory evaluation showed that the addition of MGPH to the bread only affected the aroma significantly (p < 0.05). Taken together, it can be concluded that maize germ protein hydrolysate can be used as a functional component and bread is potentially an appropriate vehicle for delivery of the biofunctional peptides.