酶解处理对竹笋膳食纤维理化特性的影响

Effects of enzymatic hydrolysis on the physicochemical properties of dietary fiber from bamboo shoot

用单一酶和复合酶在不同条件下对竹笋膳食纤维进行酶解处理,测定其膨胀力(swelling capacity,SWC)、持水力(water-holding capacity,WHC)、持油力(oil-binding capacity,OBC)等主要理化性质,并观察其微观结构的变化,从而探究酶解处理对竹笋膳食纤维理化性能的影响。结果表明:在p H=5.0,酶解温度50℃,反应时间2 h,同时添加180 U/g DF纤维素酶和90 U/g DF木聚糖酶时,竹笋膳食纤维达到最佳改性效果,其中SWC为9.29 m L/g,WHC为5.57 g/g,OBC为1.53 g/g,可溶性膳食纤维含量为12.1%。扫描电镜观察到,竹笋膳食纤维原料表面平整;单一酶处理后的竹笋膳食纤维表面粗糙,有碎屑孔隙;复合酶处理后的膳食纤维表面蓬松,有大量孔隙。复合酶处理使其具有更优势的微观结构。

The bamboo shoot dietary fiber（ BSDF） was hydrolyzed with single and composite enzymes under different conditions,and the main physicochemical properties of the hydrolyzed BSDF including swelling capacity（ SWC）,water-holding capacity（ WHC） and oil-binding capacity（ OBC）,were determined. Meanwhile,the change of the microstructure was observed. The results showed that the optimized modification conditions were as follows： p H5. 0,hydrolytic temperature of 50 ℃,reaction time of 2 hours,simultaneous addition composite cellulase of 180 U / g DF and xylanase of 90 U / g DF. Under this condition,SWC was 9. 29 m L / g,WHC was 5. 57 g / g,OBC was 1. 53 g /g,and the proportion of soluble fiber increased to 12. 1%. Scanning electron microscopy exhibited that raw BSDF had smooth surface,BSDF hydrolyzed with single enzyme had rough,clastic and porous surface,and BSDF hydrolyzed with composite enzymes showed fluffy porous surface. Compared with raw BSDF and BSDF treated with single enzyme,BSDF hydrolyzed with composite enzymes possessed preferential microstructure.