Influence of extrusion processing on the structure, physicochemical properties and in vitro digestibility of chickpea starch
摘要
This study aims to elucidate the effects of temperature-dependent extrusion processing on the structural, physicochemical, and digestibility properties of chickpea starch (CS). The results indicate that as the extrusion temperature increases, the apparent amylose content of CS rises from 16.7% to 23.45%. Analytical techniques including differential scanning calorimetry (DSC), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and Raman spectroscopy consistently demonstrate that higher extrusion temperatures lead to a reduction in gelatinization enthalpy and a disruption of the crystalline structure. Both the relative crystallinity (RC) and the R1047/1022 ratio exhibit a downward trend, suggesting that during the extrusion process, both the long-range and short-range ordered structures of the chickpea starch are compromised. Nevertheless, rheological analysis reveals that all samples exhibit a tan δ < 0.1, indicating that the modified samples retaine a robust and stable strong-gel network structure. In vitro digestibility experiments demonstrate that as the temperature increases, the content of resistant starch (RS) gradually rises while the content of rapidly digestible starch (RDS) correspondingly decreases, thereby exerting an inhibitory effect on the digestion process of the chickpea starch. Consequently, this study could provide valuable theoretical insights for the development and utilization of extruded legume starches.