Physical and enzymatic modifications of starch from blue highland barley and their characterizations, digestibility, and lipolysis inhibitory activities

The goal of this study was to investigate the differences in the physicochemical characteristics, digestibility, and lipolysis inhibitory potential of blue highland barley resistant starches (BHRSs) produced by autoclaving (BHSA), microwave-autoclaving (BHSM), isoamylase (BHSI) and pullulanase (BHSP) debranching modifications. Results showed that the resistant starch amount of native starch was evidently elevated following modifications while remaining slightly variable across BHRSs. In comparison to BHSI and BHSP, BHSA and BHSM had noticeably larger swelling powers and water-binding capabilities with reduced amylose contents and solubilities (p < 0.05). BHSP, which had a combination of CB- and V- type polymorphs, demonstrated the highest degree of crystallinity and crystalline region. BHSA and BHSM, on the other hand, were distinguished by their substantial proportion of the amorphous region with a combination of B- and V- type polymorphs. Owing to the structure diversities, structure-based morphology, and particle sizes of BHRSs, the strongest inhibitory activities on lipolysis were found in BHSA and BHSM, while the lowest digestibility was observed in BHSP. This study provided significant insights into developing the modified native starch from blue highland barley as an alternative functional food.

Automated summary

The aim of this study was to investigate the differences in physicochemical characteristics, digestibility, and lipolysis inhibitory potential of blue highland barley resistant starches (BHRSs) produced by different modifications. Results showed that the amount of resistant starch in native starch increased significantly after modifications, with some variations among the BHRSs. BHSA and BHSM had higher swelling powers and water-binding capabilities, lower amylose contents and solubilities compared to BHSI and BHSP. BHSP demonstrated the highest degree of crystallinity and crystalline region while BHSA and BHSM had a substantial proportion of the amorphous region. BHSA and BHSM showed the strongest inhibitory activities on lipolysis, while BHSP had the lowest digestibility. This study provided insights for developing modified native starch from blue highland barley as a functional food.