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; RIZZI, CORRADO; SIMONATO,BARBARA; FONTANA, ARIEL; TIRONI, VALERIA

Barcelona

Conferencia; The 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 functional ingredient. Otherwise, amaranth flour (AF) presents interesting nutritional and functional properties, including antioxidant capacity (AC). Unfermented GP (Vitis vinifera Cabernet Sauvignon) 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 and breads and digested breads were characterized. A simulated gastrointestinal digestion (SGID) was performed involving oral, gastric, and intestinal stages. The PCs obtained by different extraction protocols (MeOH/HCl 97/3 or MeOH/water 70/30) were analyzed. Total phenolic content (TPC) was determined by the Folin-Ciocalteau method and the PCs profiles and concentration by LC-DAD-FLD. AC was evaluated by ABTS and ORAC.The TPC of flours extracted by both methods was WF < AF