Enhancement of Biscuit Quality and Stability with Addition of Acorus calamus Phenolic Extract

Abstract

This study investigated the effect of different solvents on the extraction yield, phenolic profile, and antioxidant activity of Acorus calamus roots, as well as the impact of incorporating the phenolic extract into biscuit formulations. Among the tested solvents, 70% ethanol extract yielded the highest extraction efficiency (20.2%) and exhibited strong total phenolic content (86.96 mg/g) with potent antioxidant activity (DPPH: 89.29%; ABTS: 88.54%). Methanol 80% extract showed the highest total phenolic content (105.35 mg/g). Major phenolic compounds identified included chlorogenic acid, gallic acid, caffeic acid, rutin, and quercetin, with their levels varying across solvents. Biscuits enriched with increasing concentrations of Acorus calamus 70% ethanolic (100, 200, 300 ppm) demonstrated elevated total phenolic content (from 30.5 to 58.9 mg GAE/g at zero time) and reduced peroxide values over 3 months of storage (from 5.8 to 3.3 meq/kg at 3 months). Texture analysis showed decreased hardness and increased crispness and cohesiveness. Color analysis revealed a gradual darkening of biscuits with higher extract concentrations. Differential Scanning Calorimetry (DSC) indicated enhanced thermal stability in fortified biscuits, with increasing onset and peak gelatinization temperatures. These results suggest that Acorus calamus phenolic extract is a promising natural additive for enhancing the nutritional and storage qualities of bakery products.