Abstract

Mung bean (Vigna radiata (L.) Wilczek) seed coat (MBSC) is an underutilized by-product rich in vitexin and isovitexin, but its potential as a source of spray-dried functional powders has not been systematically evaluated. This study investigated the spray drying of MBSC extract using three structurally distinct polysaccharide-based carriers—maltodextrin, trehalose, and inulin—to compare their effects on process yield, powder quality, and the content of phenolic compounds, flavonoids, and antioxidant activity. Response surface methodology (RSM) with a Box–Behnken design was employed to examine the influence of inlet temperature (130–160 °C) and carrier concentration. Maltodextrin provided the highest process yield (84.85%), while trehalose and inulin formulations exhibited stronger antioxidant activity, with the lowest DPPH IC50 values of 0.096 mg/mL and 0.100 mg/mL, respectively (expressed per mg of spray-dried powder). Trehalose yielded the highest total phenolic content (TPC = 28.12 mg GAE/g extract) and acceptable flowability (Carr’s index = 20.72%). Inulin gave the highest total flavonoid content (TFC = 126.8 mg QE/g extract) but showed greater variability, attributed to its polymeric network and higher hygroscopicity. The RSM models showed high predictive accuracy for TPC (R2 > 0.98) and DPPH antioxidant activity (R2 ≈ 1.00). These findings offer a multi-objective optimization framework that links carrier structure to powder performance, providing practical guidance for selecting polysaccharide carriers in the development of spray-dried nutraceutical and functional food ingredients. However, direct measurement of encapsulation efficiency, particle morphology, and storage stability was beyond the scope of this study and warrants further investigation.

IPC Classification

Keywords