常压水热处理下红芸豆细胞中淀粉颗粒及其体外消化特性的变化

Changes in Starch Granules and In Vitro Digestibility Properties of Red Kidney Bean Cells under Atmospheric Hydrothermal Treatment

摘要:

为探究不同温度和时间的热处理对杂豆内含淀粉结构及体外消化性的影响，该研究以红芸豆为对象，通过常压水热加工获取红芸豆细胞，并结合形态学、X射线衍射、热力学性质及体外模拟消化等手段分析其内含淀粉结构及体外消化性变化。结果显示，80~100 ℃处理的红芸豆细胞均保持形态完整，细胞内淀粉未完全糊化，晶体结构被部分破坏但仍保持一定相对结晶度（12.97%~16.54%）。相较于处理时长，温度对淀粉结晶结构的影响更为显著。随热处理温度升高（80~100 ℃）及时间延长（25~45 min），细胞内异硫氰酸葡聚糖探针的荧光强度增强，淀粉体外消化速率增大，消化程度升高（56.25%~69.25%）。80/90 ℃时，细胞壁通透性是淀粉消化性的主要影响因素；当升温至100 ℃时，淀粉消化性可能受细胞壁通透性和晶体变化共同影响。因此，调节常压水热加工的温度及时长，可有效调控红芸豆细胞内含淀粉的消化特性。该研究有助于揭示杂豆在热加工过程中淀粉组分的营养特性变化规律，为杂豆功能性食品开发提供一定理论指导。

Abstract:

Red kidney bean cells were isolated under atmospheric pressure hydrothermal treatment with varying temperatures and incubation time to elucidate the effects on the structural and in vitro digestibility of starches in cells. A comprehensive analysis was conducted using a combination of morphological analysis, X-ray diffraction, thermal properties, and in vitro simulated digestion methods. The results indicated that the red kidney bean cells isolated under 80~100 ℃ all maintained morphological integrity. The starch within cells was not fully gelatinized, and the crystal structure was partially disrupted, retaining a certain degree of relative crystallinity (12.97%-16.54%). Compared to processing duration, temperature imposed a more significant impact on the starch crystal structure. As the hydrothermal treatment temperature increased (80~100 ℃) and duration extended (25~45 min), the intracellular fluorescence intensity of FITC-dextran intensified, the in vitro starch digestibility increased from 56.25% to 69.25%. At 80/90 ℃, cell wall permeability would predominantly influence the starch digestibility properties. While, both cell wall permeability and starch crystallinity would simultaneously affect the starch digestibility in cells when the temperature rose to 100 ℃. Therefore, by modulating the temperature and duration of atmospheric pressure hydrothermal processing, the digestive properties of starch contained in red kidney bean cells can be effectively regulated. This study helps to reveal the changes in the nutritional characteristics of starch components in legumes during thermal processing, providing theoretical guidance for the development of legume-based functional foods.