Abstract
The growing demand for alternative plant-based proteins, coupled with the limitations of the sources currently available, highlights the importance of exploring novel options such as Xuta (edible Jatropha curcas L.), a promising though little known protein-rich crop. In this study, the quality, digestibility, and amino acid (AA) profiles of Xuta proteins were investigated, focusing on the influence of cultivar and harvest year, and comparing the results with those of common plant-based protein sources. Protein digestibility was assessed using the standardised in vitro digestion model INFOGEST, with the protein profiles analysed at each stage of digestion. Shotgun proteomics was performed to compare the protein composition across the digestive phases. Post-digestion AA profiles and their transepithelial transport were determined using a Caco-2/HT29-MTX intestinal co-culture model. The effects on the intestinal barrier integrity were assessed via transepithelial electrical resistance and paracellular permeability measurements. Xuta proteins were found to be comparable in digestibility to conventional plant proteins, resulting in high peptide and AA release during digestion and good essential AA profiles, while digestibility varied by harvest year. Notably, Xuta digests had no adverse effects on intestinal barrier function. These findings suggest that Xuta is a valuable alternative protein source offering favourable digestibility without compromising intestinal barrier integrity.