Techno-Functional and Antioxidant Properties of Chickpea Proteins Interacted with Green Tea Phenolics-Exploring Benefits for Gel and Emulsion-Based Vegan Foods

Abstract

This study aimed at exploiting protein-polyphenol interactions to enhance techno-functional and antioxidant properties of chickpea proteins. For this purpose, prior to protein extraction, chickpeas were rehydrated in green tea infusion (GTI). Extracted chickpea proteins (CPCGTI) contained free (90.7 mu g/g) and bound (32.0 mu g/g) green tea phenolics (e.g., gallic acid, catechin, epigallocatechin 3-gallate, epicatechin 3-gallate). A close association between chickpea protein and green tea polyphenols was determined considering pH-solubility profile of CPCGTI. CPCGTI showed superior antioxidant potential (6.5-fold), water/oil absorption capacity (1.4-1.5-fold), and gel firmness than control chickpea protein (CPCC). Edible films of CPCGTI also showed 2.4-fold higher antioxidant capacity than those of CPCC. CPCGTI and CPCC showed similar SDS-PAGE patterns, but different alpha-helix and beta-sheet contents evaluated by FTIR. CPCGTI gave thick, creamy and stable mayonnaise while CPCC failed to form mayonnaise. The coconut milk pudding with CPCGTI showed better gelation than that with CPCC. However, foods with CPCGTI had a darker color than those with CPCC. CPCGTI is a novel, highly functional ingredient for manufacturing plant-based food and edible packaging.