【作者】 张雪春；

【导师】 涂宗财；

【作者基本信息】 南昌大学 ， 粮食、油脂及植物蛋白工程， 2007， 硕士

【摘要】 本论文分别研究了不同浓度和温度的花生分离蛋白溶液经过超高压微射流不同次数、压力均质后的功能性质变化情况，以及结构变化机理。结果表明：1．花生浓缩蛋白可通过碱提酸沉法批量生产花生分离蛋白，得出花生浓缩蛋白生产为花生分离蛋白的较优工艺条件；生产出来的花生分离蛋白用于后期的实验。2．均质次数超高压微射流均质次数对花生分离蛋白溶液的溶解性、乳化和乳化稳定性、起泡性和起泡稳定性没有大的影响，但经过超高压微射流均质二次和三次后，花生分离蛋白溶液的黏度略为变小，并且更趋向于牛顿流体的流变特性。3．均质压力花生分离蛋白溶液的溶解性、起泡性和起泡稳定性、凝胶强度随着超高压微射流均质压力的增大而增大，但达到一定压力后会有所下降：花生分离蛋白溶液的乳化性和乳化稳定性经过超高压微射流均质后略为增大，但总的来说变化不大；花生分离蛋白溶液经过超高压微射流均质后黏度变小，在某些压力下的花生分离蛋白溶液的流变特性呈现出接近于牛顿流体的性质，形成的膜的抗机械性能也变小了。4．花生分离蛋白溶液的浓度超高压微射流均质对低浓度的花生分离蛋白溶解性的提高更为显著；可以增大低浓度的花生分离蛋白溶液的乳化性和乳化稳定性，但对高浓度的花生分离蛋白溶液乳化性和乳化稳定性起负面作用；可以增大低浓度的花生分离蛋白溶液的起泡性和起泡稳定性，但当浓度增大后，花生分离蛋白溶液的起泡性增大的幅度有所减小；对低浓度的花生分离蛋白溶液的黏度影响不大，而高浓度的花生分离蛋白溶液的黏度较大，经过超高压微射流均质后，有变小的趋势，溶液的流型趋近于假塑性流体流变特性。5．花生分离蛋白溶液的温度超高压微射流均质对特定温度范围内的花生分离蛋白溶液的溶解度、黏度和流变特性影响不大；对花生分离蛋白溶液的乳化性和乳化稳定性、起泡性和起泡稳定性的影响也不大，但是达到最高值时的压力不一样。6．超高压微射流均质对花生分离蛋白功能基团的影响花生分离蛋白溶液经过超高压微射流均质后，蛋白颗粒的尺寸减小并分散得更均匀：巯基含量随着压力的增大有减小的趋势；表面疏水性和具紫外吸收的基团含量随着压力的增大有增大的趋势：且花生分离蛋白经过超高压微射流均质后，蛋白质的热稳定性得以提高了。7．为了更深入研究超高压微射流均质对花生分离蛋白的改性机理，本论文将花生球蛋白从经过超高压微射流均质后的花生分离蛋白溶液中提取出来，研究其二级结构以探索其改性的机理。傅立叶红外光谱测定的结果表明，花生球蛋白的α-螺旋吸收峰波长经过超高压微射流均质后有蓝移的趋势：β-折叠吸收峰波长经过超高压微射流均质后有红移的趋势；圆二色谱分析结果显示，经过超高压微射流均质后，花生球蛋白的α-螺旋结构和β-转角的含量明显减少，β-折叠和无规卷曲的含量明显增多了。8．为了推广超高压微射流技术在食品工业中的应用，本论文测评了经过超高压微射流均质后的花生蛋白的安全性，结果表明，经过超高压微射流均质后的花生蛋白样品不影响小鼠的正常生长，对小鼠的活动情况、进食量、外表特征均无不良影响，体重增长量与对照组无明显差异，病理检查显示无明显病理变化。因此经过超高压微射流均质后的花生蛋白没有毒副作用，是安全的。同时也说明超高压微射流技术对花生分离蛋白改性是一种安全的物理改性技术，可以在食品工业中大力推广。更多还原

【Abstract】 This article treated different concentrate and temperature peanut protein solution at different microfludization(HPM) pressure and different times, then studied the effect of microfludization on functional properties of peanut protein and mechanism of modification. The results indicates:1. We produced peanut protein isolate(PPI) from peanut protein concentrate in laboratory, then got the best technology parameter, and the produced PPI was used in the later stage study.2. Homogen times HPM treated circles did not affect the solubility, emulsibility and emulsive stability, foaming and foaming stability significantly, but the viscosity of PPI solution decreased slightly and tend to show the rheology characteristics of Newton fluids when treated with HPM twice and three times.3. Homogen pressure The solubility, foaming and foaming stability, the gelatinous strength of PPI solution increased linearly with HPM pressure in definite extent, but decreased when exceed the definite pressure; the emulsibility and emulsive stability of PPI solution increased slightly when treated with HPM, but did not change a lot all in all; the viscosity of PPI solution decreased when treated with HPM, some samples showed the rheology characteristics of Newton fluids; the thecal mechanical function of PPI treated with HPM decreased, too.4. Concentration HPM can improved the solubility, emulsibility and emulsive stability of PPI soluteon at low concentrateions, but the emulsibility and emulsive stability decreased at high concentrateions; and the foaming and foaming stability of PPI soluteion increased at low concentrateions, but the increasement was small when at high concentrations; HPM did not affect the viscosity of PPI soluteion at low concentrations, but the viscosity of PPI soluteion at high concentrations decreased when treated with HPM, and tended to showed the rheology characteristics of pseudoplastic fluids.5. Temperature There is no visible differences among PPI solution treated with HPM at different temperatures. The solubility, viscosity and rheology characteristics did not changed significantly at different temperatures; and temperature did not affect the emulsibility and emulsive stability, foaming and foaming stability notablly, but the pressure arrived maximal value changed.6. HPM effect on functional groups of peanut protein, the size and density of PPI treated with HPM decreased; the content of hydrosulfide group decreased with the HPM pressure increasing; the hydrophobicity and ultraviolet absorption residues increased linearly with the pressure; and the heat stability of HPM treated PPI increased.7. To study the HPM modification mechanism further, this article extracted arachin from the PPI solution treated with HPM, then analyzed the advanced structure of modified arachin to get the modification mechanism. The FT-IR spectrum results indicated, the content ofβ-plate sheet structure of arachin is far more than theα-helical structure, the absorption wavelength ofα-helical structure in amides III area all blue shift, andβ-plate sheet structure red shift. The analyze result of CD spectrum indicates, theα-helical structure andβ-corner of arachin treated with HPM decreased obviously, theβ-plate sheet structure and random coil structure creased obviously.8. To extend the application of mocrofluidization in food Industry, this article measured the safety of PPI treated with HPM, the results indicated, PPI treated with HPM did not affect the normal growth, activity information, food intake and outward appearance characteristic of mice, and the body increasement is similar to the control samples, no pathologyical change was found. So PPI treated with HPM is safe and has no side effect, this technology can extend to the food Industry.更多还原