Abstract
As the demand for sustainable, plant-based protein sources continues to grow, there is increasing interest in identifying new ingredients for food enrichment. This research explores the nutritional and digestive impacts of adding RuBisCO to wheat dough, comparing to pea protein or gluten addition. Wheat doughs were fortified with 10% external proteins and thermally treated to mimic bread food. Amino acid composition, COST standardized static in vitro digestion, degree of hydrolysis, and nitrogen/protein solubility, were conducted to assess the quality and digestibility of these enriched doughs. The results revealed that RuBisCO and pea proteins enhanced the chemical score and the in vitro PDCAAS (IV-PDCAAS) score of the wheat dough compared to the gluten control. Digestibility assessments indicated that RuBisCO modified the kinetics of protein hydrolysis: nitrogen release was lower during gastric digestion but higher during intestinal digestion than in other samples. Size-exclusion chromatography of the digesta's soluble and insoluble parts showed that the protein network in RuBisCO-enriched dough was more resistant to gastric hydrolysis than in other doughs. These findings are analyzed considering the sites of enzymatic cleavage, the presence of enzyme inhibitors, the state of protein aggregation, and the secondary structures within the protein network of each dough type.