脱脂椰蓉可溶性膳食纤维制备工艺及单糖组成和理化特性分析

Preparation, Monosaccharide Composition and Physicochemical Properties of Soluble Dietary Fiber from Defatted Coconut Meal

以脱脂椰蓉为原料,采用响应面分析法建立酶-化学法提取可溶性膳食纤维得率的二次多项数学模型,并验证数学模型的有效性。探讨酶添加量、酶解时间、碱添加量、碱解时间因素对可溶性膳食纤维得率的影响,优化提取工艺参数,确定最佳提取工艺参数为混合酶添加量0.5%、酶解时间50 min、碱液(NaOH溶液)质量分数5%、碱解时间40 min,在此条件下椰蓉粕可溶性膳食纤维得率达11.78%,持水性、持油性和膨胀性分别为3.8 g/g、5.2 g/g和3.1 mL/g。红外光谱分析发现,脱脂椰蓉可溶性膳食纤维处于缔合状态的氢键较多;高效液相色谱结果表明,可溶性膳食纤维含有9种单糖,其中甘露糖、氨基半乳糖、半乳糖、阿拉伯糖含量较高,分别为537.21、40.38、39.48 mg/L和15.83 mg/L。

Response surface methodology was employed to optimize the process parameters for enzyme-assisted alkaline extraction of soluble dietary fiber(SDF)from defatted coconut flour.A quadratic polynomial model was built and validated.The yield of SDF was investigated with respect to four variables,enzyme concentration,enzymatic hydrolysis time,alkali concentration and alkaline hydrolysis time.The optimized conditions were as follows:enzyme concentration(α-amylase+glucoamylase,1:1)0.5%,enzymatic hydrolysis time 50 min,NaOH concentration 5%,and alkaline hydrolysis time 40 min.Under these conditions,the yield of SDF was 11.78%,and the water-holding capacity,swelling-capacity and oil-holding capacity of the SDF obtained were 3.8 g/g,3.1 mL/g and 5.2 g/g,respectively.Infrared spectral analysis indicated that there were a large number of hydrogen bonds in the associated state in the SDF.HPLC results indicated that the SDF was composed of 9 monosaccharides,with mannose,galactose,galactosamine and gum sugar being predominant(537.21,39.48,40.38 and 15.83 mg/L,respectively).