DRYING OF DISTILLERS SPENT GRAIN FROM BOURBON PRODUCTION: KINETICS, MOISTURE DIFFUSIVITY, AND PHYSICOCHEMICAL PROPERTIES ANALYSIS

Abstract

The drying kinetics and physicochemical properties of wet distillers spent grain (DSG-B) derived from bourbon production were investigated to enhance the drying process and the utilization of the nutrient-rich by-product. The wet DSG-B was obtained by centrifugation of stillage, the main co-product of bourbon distilling. It was then dried at three temperatures (45°C, 55°C, and 70°C) using hot air drying. We assessed the physicochemical properties of DSG-B and calculated effective moisture diffusivity based on Fick's law of diffusion. The results revealed no significant differences in physicochemical properties across the drying temperatures; however, variations were observed compared to freeze-dried samples. The effective moisture diffusivity was 1.32×10-9 (m2/s), 1.49×10-9 (m2/s) and 2.38×10-9 (m2/s) at 45°C, 55°C, and 70°C, respectively. The study provides insights into the effect of drying conditions on the physicochemical properties of DSG-B, with application in drying process optimization of DSG-B and enhances the utilization of bourbon distilling waste.