Size-controlled interfacial crystallization of A-type resistant starch microparticles via acetone precipitation

Abstract

Short-chain glucan (SCG) recrystallization has emerged as an effective approach for producing resistant starch microparticle (RSP), which hold promise in both food science and clinical nutrition. This study introduces a novel method utilizing Tween 80 (TW80) to mediate the interfacial recrystallization of SCG into A-type crystalline RSP (ARSP) through acetone precipitation. TW80 plays a crucial role by stabilizing water-in-oil microemulsion droplets within acetone-oil mixtures, facilitating the formation of uniform and spherical ARSP ranging in size from 0.2 μm to 2 μm. The surface characteristics of ARSP, including porosity and smoothness, are notably influenced by SCG concentration. As SCG concentration increases, the melting temperature of ARSP rises from 117 °C to 145 °C, accompanied by a decrease in average surface area from 12.07 to 8.35 m2/g, alongside an increase in crystallinity. Moreover, the in vitro digestion test revealed that the digestion rate of ARSP was decreased from 0.73 h−1 to 0.39 h−1 with increasing SCG concentration, while increasing the resistant starch (RS) content in ARSP from 48.6% to 70.5%. This enhancement offers a strategic approach for modulating the digestion rate of ARSP, presenting opportunities for tailored release profiles and improved stability in food science applications. These findings underscore the potential of ARSP as a functional ingredient with significant implications for nutritional and clinical settings.