【作者】 张兴中； 李斌； 刘石林；

【Author】 Zhang Xingzhong;Li Bin;Liu Shilin;College of Food Science & Technology,Huazhong Agricultural University;

【机构】 华中农业大学食品科学技术学院；

【摘要】 选择绿色、安全、可持续、易降解的生物聚合物固体颗粒来制备稳定的食品级Pickering乳液是一项具有挑战性的工作。利用多糖与蛋白粒子复配协同稳定Pickering乳液,简单便捷、低成本、绿色安全,能够改善胶体颗粒的界面吸附性能,进一步提高制得乳液的物化稳定性。我们用大豆分离蛋白(SPI)纳米粒子与细菌纤维素互作形成复合固体颗粒,并用来稳定O/W型Pickering乳液。重点探究不同pH、纤维/蛋白质比例条件下复合物粒子在油水界面的相互作用,界面张力与弹性模量的变化,比较制得乳液的形貌结构、流变性能与稳定性。结果表明,SPI的添加显著改善了细菌纤维素表面疏水性,复合物呈现较好的界面流变性能。大豆蛋白粒子与细菌纤维素比例为12.5:1,pH为3时,油水界面张力平衡值最低且具有较高的粘弹模量。制得的乳液粒径较小且更为均匀,且长时间内(30 d)粒径与Zeta电位变化较小,流变分析可见乳液的弹性模量始终大于损耗模量,具有弹性的类凝胶结构。纤维/蛋白质复合稳定的乳液呈现较好的贮藏稳定性,在食品工业中具有广泛的应用前景。更多还原

【Abstract】 It is a challenging task to prepare stable food-grade Pickering emulsions by choosing a kind of green,safe,sustainable and degradable solid polymer particles.It is a facile way to synergistically stabilize Pickering emulsions using polysaccharide and protein particles,which is convenient,low-cost,green and safe.It can improve the interfacial adsorption performance of colloidal particles,and further facilitate the physical and chemical stability of the obtained emulsions.Here,we provided a facile way to prepare high-stable O/W Pickering emulsions stabilized by surface-modified TEMPO-oxidized bacterial cellulose(TOBC) with soybean protein isolate(SPI) nanoparticles.The effects of pH,cellulose/protein ratio on the interaction of composite particles at the oil-water interface,the change of interfacial tension and elastic modulus had been explored,and the morphology,rheological properties and stability of the resultant emulsions had been further compared.The experimental results demonstrated that the physical modification with SPI increased the surface hydrophobicity of TEMPO-oxidized bacterial cellulose,and the complexes expressed the improved interfacial rheological properties.When the SPI/TOBC ratio was 12.5:1 at pH 3,the complexes had the lowest interfacial tension values and a relative high viscoelastic modulus.Meanwhile,the obtained emulsions showed the smaller and more uniform droplet size,and the size and Zeta potentials of emulsions changed slightly during long-term storage(30 d).Rheological analysis showed that all the emulsions exhibited gel-like behaviors where storage modulus(G’) dominated over loss modulus(G").The Pickering emulsion stabilized by SPI/TOBC complexes performed excellent storage stability,which had an extensive application prospect in food industry.更多还原