[关键词]
[摘要]
为探究不同来源膳食纤维吸附能力的差异,本研究以柚子、胡萝卜和米糠来源的不溶性膳食纤维为研究对象,比较分析了其显微结构特征、理化特性,胆酸钠吸附力与释放动力学、胆固醇吸附力、葡萄糖吸附力和亚硝酸盐清除能力等吸附特性。结果显示:胡萝卜膳食纤维是表面较光滑的球形颗粒,具有最佳的吸水膨胀力(7.92 mL/g)、胆汁酸吸附力(57.80 mg/g)与模拟肠环境(pH值7)时的胆固醇吸附力(11.72 mg/g);米糠膳食纤维呈现出粗糙多孔的不规则结构,拥有最佳的持油力(3.00 g/g)、葡萄糖吸附力(20.67 mmol/g)、亚硝酸盐吸附力 1 482.22 μg/g(pH值7),2 836.23 μg/g(pH值2)、胆汁酸阻滞力(4.47 mg/g)和模拟胃环境(pH值2)时的胆固醇吸附力(8.56 mg/g);柚子膳食纤维表现为层叠的鳞片状结构,具有最佳的持水力(15.48 g/g)、黏度和优异的胆汁酸阻滞力(3.55 mg/g)。可见,三种不同来源的膳食纤维的显微结构与理化特性各具特点,使三者的吸附特性各具差异。上述研究结果为不同种类膳食纤维在健康食品中的加工利用提供了数据支撑。
[Key word]
[Abstract]
To explore differences in adsorption capacity among dietary fiber from different sources, insoluble dietary fiber (IDF) from three different sources (pomelo, carrot, and rice bran) were selected for comparative analysis of their microstructural characteristics, physiochemical properties (including water and oil holding capacities, swelling capacity, and viscosity) and adsorption properties (including cholate adsorption capacity, diffusion kinetics of cholate release, cholesterol, glucose and nitrite absorption capacities). Carrot IDF was composed of smooth spherical particles and exhibited the strongest swelling capacity (7.92 mL/g), and cholate (57.80 mg/g) and cholesterol (11.72 mg/g) adsorption capacities in a simulated intestinal environment (pH valu 7) among the three IDFs. Rice bran IDF had a rough, porous and irregular structure and exhibited the strongest oil holding capacity (3.00 g/g), glucose adsorption capacity (20.67 mmol/g), nitrite absorption capacity (1 482.22 μg/g at pH 7 and 2 836.23 μg/g at pH valu 2), cholic acid blocking capacity (4.47 mg/g) and cholesterol adsorption capacity (8.56 mg/g) in a simulated gastric environment (pH valu 2). Pomelo IDF had a layered scale-like structure and exhibited the strongest water holding capacity (15.48 g/g), high viscosity, and excellent cholic acid blocking capacity (3.55 mg/g). The three dietary fibers from different sources had their own microstructural and physicochemical characteristics, which resulted in different adsorption properties. This study provided data support for the processing and utilization of different types of dietary fiber in health foods.
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[基金项目]
国家自然科学基金项目(31972082);广东省青年科学基金项目(2019A1515110633);科技创新战略专项资金(高水平农科院建设)(R2020PY-JG011;202108TD)