Valorization of under-utilized whey: its effect on rheological and functional properties in black wheat idli

Abstract

This study focuses on the dual objectives of utilizing dairy by-products for waste valorization and the creation of functional foods. In this study, novel functional black wheat idli was developed using paneer whey (BWP), cheese whey (BWC), and whey protein concentrate (BWWPC). Whey-enriched Idli exhibited the highest protein content (g/100 g) in WPC (24.76), paneer (20.34), and cheese whey (21.03) compared with the control (18.7). The antinutritional factors were reduced with WPC exhibiting the lowest levels of phytic acid (5.52 mg/100 g) and saponin (616 mg/100 g). Rheological evaluation demonstrated that paneer whey batter exhibited the highest elasticity (G′ = 9821 Pa). Paneer whey also improved cohesiveness (0.692) and adhesiveness (−45.12 N s), while the WPC formulation provided the firmest texture. Thermal analysis indicated that cheese whey formulations had lower gelatinization temperatures (Tp = 84.19 °C), while paneer whey exhibited higher stability (Tp = 102.84 °C). Structurally, XRD analysis revealed sharper peaks in the paneer whey formulations, indicating enhanced starch crystallinity. High-resolution accurate mass spectrometry detected more bioactive metabolites in cheese whey formulations, showing higher levels of threonine and quercetin potential for enhanced nutrient bioavailability. This approach successfully demonstrates a sustainable strategy for valorizing dairy by-products by creating a novel, nutrient-dense functional food. © 2025 The Authors.