超细水不溶性大豆皮膳食纤维理化特性的研究

Study on physico-chemical properties of ultrafine insoluble dietary fiber derived from soybean skin

水不溶性大豆皮膳食纤维通过频率分别为150、250、300Hz的气流粉碎机粉碎,得DF-A、DF-B、DF-C三种不同粒径超细膳食纤维,并对它们的理化特性进行比较研究。样品DF-C的中位粒径约为16.58μm,比样品DF-A的中位粒径降低2.5倍,而比表面积随粒径的减小呈增大趋势,最大比表面积为152.2m2·kg-1;样品DF-A、DF-B、DF-C的白度分别为51.7%、55.1%、63.4%;根据Duncan法的分析结果可知,样品DF-A与DF-B间的持油力差异不显著(p>0.05),而样品DF-A与DF-C、DF-B与DF-C间的持油力差异显著(p<0.05);样品DF-A、DF-B及DF-C间的持水力差异显著(p<0.05);阳离子交换能力逐渐增强,直到消耗0.7mL NaOH时,阳离子交换能力趋于稳定;当溶液浓度<10%时,三者溶液的黏度曲线比较陡峭,黏度值皆呈上升趋势。而扫描电子显微镜下(SEM)观察表明,膳食纤维的微观结构并没有随着其粒度的减小而发生改变,仍呈杆状结构。结果表明:气流粉碎进一步增强了水不溶性大豆皮膳食纤维保健功能特性。

To crush the insoluble dietary fiber of soybean skin through pneumatic cracker with three different frequency which was 150,250,300Hz,three different particle size of superfine dietary fiber DF-A, DF-B, DF-C were obtained,and the physico-chemical properties of them were compared. The median diameter of DF-C was 16.581μm,decreasing 2-5 times than DF-A. While the specific surface area had a trend of increasing with the particle size decreasing,the most specific surface area was 152.2m2. kg-1. The whiteness of DF-A,DF- B, DF-C were respectively 51.7% ,55.1% ,63.4%. Through the result of Duncan,the water-holding capacity of sample DF-A and DF- B had no significant difference（p〉0.05）,the oil-holding capacity of DF-A,DF-B, DF- C had significant difference （p〈 0.05 ）, the water holding capacity of DF-A, DF- B, DF- C had significant difference （p〈0.05）. The cation exchange capacity got strong gradually, until the consuming of NaOH was 0.7mL. When the solution concentration was below 10% ,the viscosity curve of them was steep,the viscosity number had rise trend. While the results of scanning electron microscope showed that the microstructure did not change with the decrease of the dietary fiber particle sizes,it still had a rod-shaped structure. Results showed that Jet mill increased the hvaiene function of insoluble dietarv fiber of sovbean skin.