动态高压微射流改性可溶性大豆多糖对大米淀粉老化特性的影响

Retrogradation of Rice Starch Inhibited by Soluble Soybean Polysaccharides Modified through Dynamic High Pressure Microfluidization

采用动态高压微射流(dynamic high pressure microfluidization,DHPM)分别在80、120、170 MPa条件下对可溶性大豆多糖(soluble soybean polysaccharides,SSPS)改性,通过扫描电镜(scanning electron microscope,SEM)和傅里叶红外光谱(fourier transform infrared spectroscopy,FTIR)比较改性前后SSPS表面形态和分子结构的变化。结果表明:改性后SSPS的主体结构基本未发生变化,只是样品内部氢键作用减弱,有序性降低;外观形态发生破碎断裂现象,形成多孔结构,整体结构变得松散。然后通过快速黏度分析仪(rapid visco analyser,RVA)、差示扫描量热法(differential scanning calorimetry,DSC)、FTIR手段研究改性后可溶性大豆多糖(modified soluble soybean polysaccharides,MSSPS)对大米淀粉(rice starch,RS)老化特性的影响。添加MSSPS组与SSPS组比较,RS糊化峰值黏度、最终黏度、回复值、糊化焓值以及FTIR图谱1 047、1 022 cm-1处的峰高比值均显著降低(P<0.05)。结果表明:添加MSSPS后,RS的老化程度显著降低(P<0.05),且改性压强增大,MSSPS抑制老化的效果显著增强(P<0.05)。

Soluble soybean polysaccharides(SSPS) were modified by dynamic high pressure microfluidization(DHPM) at 80, 120 and 170 MPa, respectively. Differences in surface topography and molecular structure between SSPS and DHPMmodified SPSS(MSSPS) were analyzed by scanning electron microscope(SEM) and Fourier transform infrared spectroscopy(FTIR). The results indicated that the hydrogen bond and internal order of samples were decreased while the major structure of SSPS was not changed by DHPM treatment. In addition, the surface topography of samples became loose as SSPS was ruptured and some cellular structures were formed. Rapid visco analyzer(RVA), differential scanning calorimetry(DSC) and FTIR were employed to investigate the effect of MSSPS on the retrogradation properties of rice starch(RS). The results showed that the peak viscosity, final viscosity, gelatinization enthalpy and setback value were significantly decreased(P < 0.05) in the gelatinization of RS with the addition of MSSPS. FTIR spectrum showed that the ratios of the peak intensities at 1 047 cm-1and 1 022 cm-1 were significantly decreased(P < 0.05) with the addition of MSSPS. These results demonstrated that the retrogradation extent of RS was decreased significantly(P < 0.05) with the addition of MSSPS. Moreover, the inhibitory effect of MSSPS on the retrogradation of RS was significantly(P < 0.05) enhanced with increasing DHPM pressure.