Exploration of grape pomace flour and amaranth flour as functional ingredients in the elaboration of breads: phenolic composition, antioxidant capacity and simulated digestion

RODRÍGUEZ, MARIELA; ALONSO, RODRIGO; SIMONATO, BARBARA; FONTANA, ARIEL; TIRONI, VALERIA

Barcelona

Conferencia; 1st International Conference on Antioxidants: Sources, Methods, Health Benefits and Industrial Applications; 2023

MDPI

Grape pomace (GP) represents the main solid by-product of the wine industry. Due to it richness in phenolic compounds (PCs), it addition to breads could be a suitable alternative for GP application as a functional ingredient. Otherwise, amaranth flour (AF) presents interesting nutritional and functional properties, including antioxidant capacity (AC). Unfermented GP (Vitis vinifera CabernetSauvignon) resulting from the production of a sparkling wine was dried (45°C) and pomace flour (GPF) was obtained (Udy mill). White wheat bread (WB) and breads with wheat flour (WF) substitutions were prepared: 5% GPF (5GPFB), 20% AF (A20B), 20% AF and 5% GPF (A20GPF5B). The original flours, breads and digested breads were characterized. A simulated gastrointestinaldigestion (SGID) was performed involving oral, gastric, and intestinal stages. The PCs obtained through different extraction protocols (MeOH/HCl 97/3 or MeOH/water 70/30) were analyzed. The total phenolic content (TPC) was determined using the Folin-Ciocalteu method and the PCs profiles and concentration through LC-DAD-FLD. AC was evaluated using ABTS and ORAC. The TPC of flours extracted using both methods was WF < AF