挤压法制备硫酸酯化苹果水溶性膳食纤维

Preparation of sulfated apple soluble dietary fibers by extrusion technology

采用挤压法研究了硫酸酯化水溶性苹果膳食纤维的制备工艺,红外光谱分析酯化前后产物结构差异,ORAC(Oxygen Radical Absorbance Capacity)荧光法测定总抗氧化值。结果表明:最佳工艺条件是氨基磺酸与膳食纤维比例3:10,浓硫酸与膳食纤维比例4:10,静置时间2 h,螺杆转速650 r/min,所得硫酸酯化水溶性膳食纤维的取代度为0.79。红外光谱表明硫酸基团已成功结合到膳食纤维多糖链段上;ORAC值表明ASDF具有较好的氧自由基清除能力(ORAC值为100.34μmol Trolox/g)。

The preparation of sulfated apple dietary fibers by extrusion was studied in this manuscript. The samples＇ structures were characterized by FT-IR, and the antioxidant activity of samples were evaluated by ORAC（oxygen radical absorbance capacity） fluorometric assay. The results indicated that the optimistic process were as follows： the ratio of amino acid and dietary fibers was 3：10, and the ratio of concentrated sulfuric acid and dietary fibers was 4：10, standing time was 2 h, screw rotation speed was 650 r/min. The degree of substitution of sulfated apple dietary fibers were 0.79. The FT-IR revealed that sulfated groups have been successfully grafted on the polysaccharide chains of dietary fibers. It is suggested that antioxidant capacity of the sulfated samples had been enhanced than before, and the ORAC value of ASDF was 100.34 μmol Trolox/g.