Structural and Physicochemical Characterization of Resistant Starch from Sixteen Banana Cultivars across Three Genome Groups

Banana fruits are rich in starch, and unripe banana flour is considered a beneficial ingredient in the food industry because it has high levels of resistant starch, which significantly aids in promoting gut health and regulating blood sugar and lipid levels. However, the associations between banana cultivars with various genotypes cultivated globally and their resistant starch properties remain unclear. Herein, we investigated resistant starches from 16 banana cultivars covering three genome groups (ABB, AAB, and AAA) in order to reveal the differences and similarities among these cultivars. The results showed that there was a genotype-specific pattern in banana resistant starch (BRS) degradation. The AAA genome BRS exhibited a high degree of resistant starch degradation. The genotypes of the banana cultivars also impacted the granular morphology of the resistant starch. The ABB and AAB genome BRS were more conducive to forming resistant starch. The BRS samples from the three genome groups displayed either B-type or C-type structures. Even within the same genome group, the BRS samples exhibited differences in thermal and pasting properties. These findings reveal the impact of genotypes on BRS content and characteristics, providing a basis for future breeding and resistant starch utilization.