Abstract
The extraction characteristics of internodes and chopped materials of sweet sorghum were investigated using a tension-meter and a compression testing machine in order to determine the optimal harvest-time, and extract sweet sorghum efficiently. The hardness and Brix value of sweet sorghum internodes increased from 15 weeks after sowing, and peaked at 16 to 17 weeks after sowing, decreased after that. Sweet sorghum should be harvested and extracted at 16 to 17 weeks after sowing, considering Brix change. A better linear logarithmic relation existed between pressure and juice extraction ratio (juice mass to input mass), and the energy efficiency of thin materials was higher than that of thick materials when chopped sweet sorghum was extracted.
