【作者】 田成；

【导师】 汪兴平；

【作者基本信息】 湖北民族学院 ， 野生动植物保护与利用， 2010， 硕士

【摘要】 我国是大豆的生产大国和消费大国,很多豆制品加工过程中都会产生大量的豆渣,其中绝大部分都没有得到良好的开发及利用,仅仅用作饲料或燃料,甚至作为垃圾直接废弃,不仅利用程度低,而且对环境造成了极大的污染。本文以豆渣作为原料,研究探讨了不溶性豆渣膳食纤维的改性工艺及其物化特性,为豆渣资源的综合利用提供理论依据及指导作用。研究结果如下：1、改性的工艺确定：用化学方法对不溶性豆渣膳食纤维进行改性处理,以持水性作为考察指标。首先进行改性试剂的筛选,然后进行单因素实验,最后采用正交设计进行工艺优化试验。实验结果表明：改性工艺的最佳条件为：磷酸氢二钠溶液浓度0.1%,料液比1：60,处理时间1h,处理温度50℃2、改性膳食纤维的水化特性显著提高。经过改性后不溶性豆渣膳食纤维的持水力为11.95g/g,膨胀力为17.90ml/g,结合水力为3.40g/g,持油力为4.35g/g,均较改性前有不同程度的提高,从而使膳食纤维的生理保健功能得到增强。3、改性膳食纤维对NO2-的吸附能力：改性膳食纤维在37℃时不同pH条件下对NO2-的吸附能力较高,但是随pH的升高而降低,pH2时为56umol/g, pH3时为53umol/g, pH5时为40umol/g, pH7时为34umol/g。4、改性膳食纤维对金属有较强的吸附能力,研究表明对Pb2+、Cu2+、Zn2+、Fe3+、Mg2+、Ca2+的吸附能力分别为0.524mmol/g、0.456mmol/g、0.040mmol/g、0.019mmol/g、0.190mmol/g、0.303mmol/g。5、改性膳食纤维的结构特点：①改性膳食纤维与商购膳食纤维的基本结构具有高度的一致性。这主要体现在二者红外光谱的高度相似性,二者具有多糖特征吸收峰,并在1000-1100 cm-1处都有磷酸基团。②X-射线衍射表明改性试剂可能使膳食纤维的结晶度和聚合度下降,使产品的结构更疏松,但是从结晶度改变的数值来看,对结构的影响有限。③DSC曲线的差异说明改性膳食纤维比商购膳食纤维成分单一,纯度高,而且吸附水的能力更强。④扫描电子显微镜观察结果显示,改性膳食纤维颗粒比商购膳食纤维颗粒更微小,表面略有褶皱,结构疏松,带有明显的片状结构,颗粒的表面出现蜂窝状结构,且分布均匀。综上所述,X-射线衍射、DSC曲线测定、扫描电子显微镜观察均证明以磷酸氢二钠作为改性试剂,在本工艺条件下,对大豆膳食纤维的结构起到了一定的改性作用。改性膳食纤维的水化特性和吸附特性得到有效改善,可以预测其生理功能和食品加工特性将有进一步改善。因此,本文研究的改性不溶性豆渣膳食纤维具有良好的开发前景,且加工工艺简单,成本较低,具有较大的开发价值。更多还原

【Abstract】 Every year our country brings and consumes plenty of soy bean, so there will be lots of soybean residue and soybean hull, much of which have not been well developed and used, only a little of which have been used as feed or fuel, or even scraped. The low utilization also caused great pollution to environment. This paper takes soybean residue as material and studies its insoluble dietary fiber modification technology and its physichemical properties. The whole data from experimentations provides theoretic gist for the synthetically using of soybean residue. The following are the main contents and results of the test.1. Determine of modification process:take the water binding capacity as examine items and using chemical method to modify insoluble dietary fiber on the soybean residue. The single-factor experiment has been done after screening best Modify reagents. It has been shown from the orthogonal test that the optimum modification process is respectively 0.1%for concentration of disodium hydrogen phosphate,50℃for heating temperature,60minute for heating time and 1:60 liquid ratio. The hydration characteristics of soybean residue insoluble dietary fiber have significantly increased after modification.2. The physichemical properties of insoluble dietary fiber on the soybean residue were water-binding capacity 11.95g/g, swelling force capacity 17.90ml/g, combining water capacity 7.1g/g, and fat binding capacity4.35g/g. The modified products has a better properties then before and the physiological functions enhanced.3. Analyze the NO2- adsorption capacity at 37℃under adsorption pH=2,3,5,7 and the soybean residue insoluble dietary fiber adsorpt 56umol/g,53umol/g,40umol/g and 34umol/g, respectively. The results showed that the NO2- absorption capacity of the soybean residue insoluble dietary fiber pull down when pH increased.4. It has been shown from the study that the soybean residue insoluble dietary fiber have adsorption capacity on six heavy metal ion. The adsorption capacity was Pb2+ 0.524 mmol/g, Cu2+ 0.456 mmol/g, Zn2+ 0.040 mmol/g, Fe3+ 0.019 mmol/g, Mg2+ 0.190 mmol/g, Ca2+ 0.303mmol/g.5. The structural characteristics of modified dietary fiber:①The modified dietary fiber and market dietary fiber has a high degree of consistency on the basic structure. It is mainly reflected in the infrared spectra, both them have characteristic absorption peaks of polysaccharide and has a peaks of phosphate group at 1000-1100 cm-1.②The X-ray diffraction show that the modification reagents may make decreased on crystallinity and polymerization degree and make the structure of the product looser, but the change to the structure was limited view from the crystallinity. ③DSC curve shows that the modified dietary fiber are single, and pure, can adsorbed more water.④Scanning electron microscopy showed that the modified dietary fiber are smaller then market dietary fiber and the surface of the tiny grain is gassy, fold, conspicuous laminated structure and has cellular structure.In conclusion, proved by the results of X-RD, DSC, SEM, the sodium hydrogen phosphate can do same modification on the structure of soybean residue insoluble dietary fiber under this process condition. The hydration properties and adsorption characteristics have been improved effectively after modification. We can predict that the physiological functions and food processing characteristics will be further improved. The modification Process of the soybean residue insoluble dietary fiber is simple, low cost and has value for development.更多还原