Unveiling the role of starch crystalline type in ultrasonic-assisted complexation with palmitic acid: Implications for physicochemical properties and enzyme resistance.

Starch crystalline type is a key structural factor influencing its interaction with lipids. This study compared how three starch crystalline types, namely A-type wheat starch (WS), B-type potato starch (PS), and C-type mung bean starch (MBS), influenced the formation and properties of starch-palmitic acid (PA) complexes under ultrasonic treatment. A-type WS formed complexes (UWS-PA-500) that exhibited the highest pasting temperature (93.82 °C) and the largest decrease in gelatinization enthalpy with ΔH reduced from 9.65 J/g to 7.95 J/g, indicating the most pronounced improvement in thermal stability. Despite a relatively low complex index, B-type PS complexes (UPS-PA-500) displayed the strongest molecular ordering of V-type helices, as evidenced by the lowest Raman FWHM (15.34) and the highest relative crystallinity (26.77%). C-type MBS complexes (UMBS-PA-500) showed the highest apparent amylose content and resistant starch content (18.37%) after complexation, suggesting superior enzyme resistance. Collectively, the results demonstrate that starch crystalline type, together with associated structural attributes such as amylose content and granule morphology, influences the complexation efficiency, structural ordering, thermal behavior, and digestibility of ultrasonic-assisted starch-PA complexes.