摘要:
为改善羟丙基甲基纤维素(Hydroxypropyl Methylcellulose,HPMC)的可加工性和成膜性,使用zein-果胶复合颗粒作为稳定剂,考查明胶(Gelatin,GA)和HPMC的复配比(0∶10、3∶7、4∶6、5∶5、6∶4和10∶0)对GAHPMC双水相体系微观结构、物理稳定性和流变特性的影响。结果表明:添加质量分数为0.3%的zein-果胶复合颗粒能降低GA与HPMC的相分离速度和相分离程度,这种稳定作用随着HPMC占比的增加(4%~7%)而增强;在zein-果胶复合颗粒质量分数相同的情况下,GA占比小于5%的体系可形成GA为分散相、HPMC为连续相的水包水结构,且随着GA占比的增加,GA-HPMC双水相体系的黏度和凝胶强度均逐渐增加;GA-HPMC双水相体系的胶凝温度(58.90~54.19℃)显著低于纯HPMC溶液(61.63℃),其胶融温度(28.80~32.23℃)的改变与GA占比呈正比。复配比对GA-HPMC双水相体系的稳定性和流变特性的影响呈相反趋势,应根据实际应用需求选择合适的复配比。
Abstract:
To improve the processability and film-forming properties of hydroxypropyl methylcellulose (HPMC),the effects of the blended ratios of GA and HPMC (0∶10,3∶7,4∶6,5∶5,6∶4,and 10∶0) on the microstructure,physical stability,and rheological properties of the GA-HPMC aqueous two-phase system were investigated by using zein-pectin composite particles as stabilizers.The results showed that adding 0.3% zein-pectin composite particles could reduce the phase separation rate and phase separation degree of GA and HPMC,and this stability effect was enhanced with increasing HPMC proportion (4%~7%);Under the same mass fraction of zein-pectin composite particles,these systems with proportion of GA<5% formed a water-in-water structure with GA as the dispersed phase and HPMC as the continuous phase,and with the increase of the GA ratio,the viscosity and gel strength of GAHPMC aqueous two-phase system increased;The gelling temperature (58.90~54.19℃) of the GA-HPMC aqueous two-phase system was significantly lower than that of pure HPMC solution (61.63℃),and its melting temperature (28.80~32.23℃) was positively correlated with the proportion of GA.The effect of the blended ratios on the stability and rheological properties of the GA-HPMC aqueous two-phase system showed an opposite trend,so a suitable blended ratio should be selected according to the actual requirements.
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