The effects of ultrasonic treatment on physicochemical properties and in vitro digestibility of semigelatinized high amylose maize starch

This study aimed to observe and quantify the high- and low-temperature ultrasonication impact of semigelatinized high amylose maize starch on physicochemical properties and in vitro digestibility. High- and low-temperature ultrasonication did not increase the degree of gelatinization, but generated cracks and pores on the starch granule surface and enhanced the short-range ordered molecular structure and apparent amylose content (AAC). Compared with incubation treatments, high-temperature ultrasonication gradually increased the slowly digestible starch (SDS) and resistant starch (RS), whereas low-temperature ultrasonication only decreased RS. Principal component analysis (PCA) and multivariate linear regression results showed that SDS and RS were significantly affected by the long-range ordered molecular structure, a molecular weight distribution of amylopectin, enthalpy change and AAC, whereas the short-range ordered molecular structure further dominated RS. Our results improved the understanding of physicochemical property changes in low- and high-temperature ultrasonication on semigelatinized high amylose maize starch and differentiated the significant principal components of SDS and RS formation.