Valorization of Dairy whey by-product in black wheat instant idli mix: Molecular, elemental, and chemometric characterization

This study developed nutrient-enriched black wheat rawa idli mix incorporating dairy whey streams. Four formulations, black wheat idli (BWI), paneer whey (BWP), cheese whey (BWC), and whey protein concentrate (BWWPC), were compared with a conventional suji control. ¹H NMR spectroscopy revealed distinct branched-chain amino acid resonances at δ 0.82–0.89 ppm, consistent with WPC incorporation. ICP-MS analysis demonstrated substantial mineral enrichment, with iron reaching 6.79 mg/100 g and manganese increasing up to 11.5-fold in BWI, while heavy metals remained within applicable FSSAI limits. Pasting analysis revealed significant reductions in peak (87%), breakdown (99%), and setback (81%) viscosities in BWWPC as compared to the black wheat control (BWI), indicating enhanced paste stability and attenuated starch retrogradation. During 120 days of nitrogen-flushed storage, most formulations-maintained moisture below 4.5% and exhibited limited lipid oxidation and microbial growth, with BWWPC demonstrating the highest overall storage stability. Chemometric evaluation via principal component analysis and hierarchical cluster analysis applied to 27 quality attributes explained 87.6 % of the total variance, enabling clear differentiation among the formulations. These findings demonstrate that whey-incorporated black wheat instant idli mix showed potential as nutrient-enriched, shelf-stable foods, with reduced retrogradation, heavy metals within FSSAI limits, and a preliminary multi-analytical approach for sustainable whey valorization.