不同品种马铃薯膳食纤维化学组成及理化性质分析

摘要

以夏波蒂、白玫瑰、黑玫瑰、克新1号、费乌瑞它、冀张薯8号6个品种的马铃薯为研究对象,自提薯渣并采用中温α-淀粉酶、碱性蛋白酶和糖化酶水解提取膳食纤维,研究了不同品种干马铃薯渣(dried potato residue,DPR)和马铃薯膳食纤维(potato dietary fiber,PDF)的化学组成、微观结构及理化性质.结果表明:不同品种DPR的各化学组分含量差异显著(P<0.05),其中夏波蒂、黑玫瑰的总膳食纤维含量较高,分别为43.16%和31.87%.PDF得率最高的是夏波蒂(62.19%),最低的是白玫瑰(42.99%),黑玫瑰为51.27%.与DPR相比,酶解后得到的PDF中淀粉和果胶含量较低,蛋白质、纤维素、半纤维素、木质素含量较高;DPR结构紧密,而酶解得到的PDF结构更疏松,有褶皱和很多空洞,表面积大.黑玫瑰PDF的淀粉含量最低,蛋白质含量为7.69%,显著低于白玫瑰(P<0.05),纤维素含量高达21.30%,木质素含量与含量最高的白玫瑰差异不显著(P>0.05),果胶含量显著高于其他品种(P<0.05).综合比较,黑玫瑰PDF的持水性、持油性、膨胀性和葡萄糖束缚能力在6个品种中均较大,因此黑玫瑰是一种适合提取PDF的马铃薯资源.%In this study, dietary fiber was extracted from the residue left after the removal of starch from 6 varieties of potato, namely, Shepody, White Rose, Black Rose, Kexin No. 1, Favorita, and Jizhangshu No. 8, by sequential hydrolysis with medium-temperature α-amylase, alkaline protease and glucoamylase. The chemical composition, microstructure, and physicochemical properties of dried potato residue (DPR) and potato dietary fiber (PDF) were studied. The results showed that the chemical compositions of DPR from different varieties were significantly different (P < 0.05). The contents of total dietary fiber (TDF) in Shepody and Black Rose were 43.16% and 31.87%, respectively. The highest yield of PDF was extracted from Shepody (62.19%), and the yield of PDF extracted from White Rose was the lowest (42.99%). The extraction yield of PDF from Black Rose was 51.27%. Compared with DPR, the contents of starch and pectin in PDF decreased due to the enzymatic hydrolysis, and the contents of protein, cellulose, hemicelluloses, and lignin increased. The structure of DPR was compact while the structure of PDF was loose with some wrinkles and microholes. The content of starch in dietary fiber from Black Rose was the lowest; the content of protein was 7.69%, which was significantly lower than that in White Rose (P < 0.05); and the content of cellulose was 21.30%. There was no significant difference (P > 0.05) in lignin between Black Rose and White Rose, which were richer in lignin than other varieties (P < 0.05). Generally, dietary fiber from Black Rose is superior to that from other varieties in terms of water holding capacity (WHC), oil holding capacity (OHC), swelling capacity (SC), and glucose binding capacity (GAC). So Black Rose is a suitable potato variety for the extraction of PDF.