How molecular, supramolecular structure and gelatinization properties of starch influence fermentation behavior of sorghum cultivars

The fermentation behavior of sorghum influences the distilled spirits quality, yet the differences among cultivars cannot be explained by amylopectin content alone. Six cultivars were studied to investigate how starch structure relates to fermentation. Fermentation stability was associated with supramolecular structure, correlating positively with single helix content ( r = 0.81, p < 0.001), crystal heterogeneity ( r = 0.62, p < 0.01), and retrograded crystal stability ( r = 0.64, p < 0.01), which support sustained substrate release. The average fermentation rate was associated with gelatinization properties, correlating with amylose ( r = 0.58, p < 0.05), short amylopectin chains ( r = 0.74, p < 0.001), and long amylopectin chains ( r = −0.74, p < 0.001). Principal component analysis revealed that gelatinization properties dominated PC1 (60.2%) and supramolecular structure dominated PC2 (23.2%), separating rapid, slow, and medium fermentation types. This study links starch structure to fermentation behavior, providing a basis for selecting sorghum cultivars for liquor production.