两种超微粉碎法对西番莲果皮水不溶性膳食纤维改性效果的研究

Effect of Superfine Pulverization Treatment on the Physicochemical Properties of Insoluble Dietary Fiber from Passiflora edulis Rind

本实验以西番莲果皮膳食纤维为原料,采用干法超微粉碎和湿法超微粉碎进行改性处理,并对改性后的膳食纤维进行形貌观察和理化性质测定。电镜扫描结果显示经两种方式改性后,膳食纤维的组织结构都有破坏,且湿法更严重;红外光谱分析结果显示改性后的膳食纤维羟基所在峰位均发生一定的蓝移,促进了羟基基团的暴露;X衍射结果显示改性后的膳食纤维晶区并未发生改变;膳食纤维改性后,持水力、膨胀力、水溶性和SDF溶出率都有所增强,尤其是经湿法改性持水力由6.739 g/g提高到20.085 g/g,增加了198.04%;但改性对阳离子交换能力影响不大;膳食纤维改性后,对脂肪酸、胆固醇、亚硝酸根离子和胆酸钠的吸附能力都有提高,且湿法强于干法。整体而言,这两种超微粉碎法对膳食纤维的改性都有效果,并且湿法对多数指标的改性效果均达到显著水平,强于干法。

The effects of superfine pulverization by wet or dry processing were observed on the characterization and physiochemical properties of insoluble dietary fiber from Passiflora edulis rind. Scanning electron microscopy（SEM） showed that the microstructure of dietary fiber was destroyed by both methods, but the effects were more significant with wet processing of insoluble dietary fiber（WIDF）. Fourier transform infrared spectroscopy（FT-IR） revealed that hydroxyl group peaks showed a hypsochromic shift after processing, which indicated that more hydroxyl groups were exposed in the modified dietary fiber. X-ray diffraction（XRD） curves showed that the crystalline region of the modified dietary fiber had not changed. The water holding capacity, swelling capacity, water solubility, and dissolution rate of soluble dietary fiber（SDF） were increased. In particular, the water holding capacity of the wet modified dietary fiber was increased from 6.739 g/g to 20.085 g/g, an increase of 198.04%. The cation exchange capacity increased slightly after wet processing, but was not significantly different from that of dry processing. The adsorption capacities for aliphatic acid, cholesterol, nitrite ion, and sodium cholate were increased, and were significantly better after wet processing. Overall, superfine pulverization by wet or dry processing had significant effects to improve the features of dietary fiber. Moreover, the results showed that wet superfine pulverization produced better effects than dry superfine pulverization.