Assessment of bioactive compounds and their in vitro bioaccessibility in whole-wheat flour pasta

We studied the polyphenol profile and antioxidant properties of cooked whole-wheat pasta to evaluate its effective antioxidant capacity, including changes produced by its production and in vitro digestion. The polyphenol profile was studied by HPLC-ESI-MS/MS, while the antioxidant capacity was measured by TEAC and FRAP assays. Results show that the polyphenol profile and antioxidant capacity change along the elaboration of cooked pasta, being the cooking step important to increase the release of bound polyphenols, enhancing their antioxidant properties. On the other hand, the study of the bioaccessibility of polyphenols, using an experimental model that simulates human gastrointestinal digestion and subsequent absorption, showed that only a small fraction of the starting polyphenolic compounds, mainly free polyphenols, could be absorbed by the small intestine; thus, reducing their effective antioxidant capacity. To our knowledge, this is the first report showing the bioaccessibility of hydroxybenzoic acid glucoside, hydroxybenzoic acid diglucoside, tryptophan, 6-C-glucosyl-8-C-arabinosyl-apigenin and diferulic acids.