Starch Fermentation Characteristics for Different Proportions of Amylose and Amylopectin

The amylose: amylopectin ratio in corn starch is known to affect its chemicalcharacteristics. Yellow dent corn contains 20 to 30% amylose and 70 to 80% amylopectin. Effectsof amylose: amylopectin ratios on corn starch fermentation characteristic were investigated. Commercially available starches Hylon VII (70% amylose and 30% amylopectin) and Amioca (100%amylopectin) were mixed in varying proportions. Fermentations were performed using granularstarch hydrolyzing enzyme and conventional enzymes. Differences were found in ethanol yieldamong starches containing different ratios of amylose and amylopectin and among enzymes used.Ethanol concentrations varied from 2.2 to 9.1 (% v/v) for fermentation with granular starchhydrolyzing enzyme and from 6.7 to 9.3 (% v/v) for conventional enzymes.