Effect of Solubles on Disintegration of Distiller's Spent Grain Compacts During Superheated Steam Drying

摘要

Drying of densified spent grain in superheated steam (SS) may cause breakage and disintegration of the product in the initial stage of SS drying. The present work investigated the effect of solubles (0, 10, 30, 50, and 70% solubles) on the percentage change in length, diameter, volume; hardness; and the asymptotic modulus (EA) of the cylindrical compacts during SS drying. An increase in dimensions along with a decrease in hardness and EA of the compact was observed immediately after exposing it to SS. We observed a 47% increase in length and 12% increase in diameter for compacts having 0% solubles during the first five seconds of SS drying; however, when the soluble content increased to 70%, the percentage increase in length and diameter became 12 and 2%, respectively. Also, with an increase in the amount of solubles in the compact, a considerable increase in the hardness and EA of the compact was observed. The study also aimed to find suitable explanatory variables for predicting the hardness and EA of the compact using a stepwise forward regression method.