多糖添加对兔肌原纤维蛋白Pickering乳液稳定性及凝胶特性的影响

薛山; 罗娟

doi:10.13386/j.issn1002-0306.2022110340

多糖添加对兔肌原纤维蛋白Pickering乳液稳定性及凝胶特性的影响

薛山,
罗娟

Effect of Polysaccharide Addition on the Stability and Gel Properties of Rabbit Myofibrillar Pickering Emulsion

Shan XUE,
Juan LUO

摘要

摘要: 本研究提取兔肉肌原纤维蛋白（Rabbit Myofibrillar Protein，RMP），以大豆油为油相制备Pickering乳液及乳液凝胶，考察不同pH环境（3~10）、不同浓度卡拉胶（0.25%～0.50%）和海藻酸钠（0.25%～0.50%）添加对Pickering乳液稳定性及其凝胶特性的影响，以期利用RMP制备高稳定性Pickering乳液凝胶。结果表明：当pH为9时，RMP乳液的ζ-电位绝对值最大（33.60 mV）；在pH为9，油相体积50%，卡拉胶和海藻酸钠多糖添加浓度均为0.35%时，RMP-Pickering乳液的ζ-电位绝对值（72.97±0.60）、乳化指数（Emulsifying Activity Index，EAI）（5.09±0.09 m²·g⁻¹）和乳化稳定指数（Emulsifying Stability Index，ESI）（46.07%±3.74%）均达到最大值；在多糖浓度0.25%~0.35%范围内时，卡拉胶和海藻酸钠添加的RMP-Pickering乳液凝胶的持水性、硬度和弹性均逐渐升高，二者均在添加浓度0.35%时达到最大值，且当多糖浓度在0.35%~0.50%范围内时，海藻酸钠-RMP乳液凝胶较卡拉胶-RMP乳液凝胶具有更低的硬度和更高的持水性与弹性；红外光谱分析显示随着多糖浓度的增加，两种多糖稳定的RMP乳液凝胶β-折叠含量均呈现先增加后减少的趋势，蛋白质二级结构由无序变得有序，在两种多糖浓度均为0.35%时，β-折叠含量达到最大值（卡拉胶：30.34%±0.04%，海藻酸钠：29.70%±0.12%）；由宏微观结构及凝胶作用力分析可知，疏水相互作用和二硫键均在卡拉胶-和海藻酸钠-RMP Pickering乳液凝胶维持凝胶结构中发挥了作用。综上，当卡拉胶和海藻酸钠的终浓度均为0.35%时，能够使多糖-RMP-Pickering乳液体系分布更加均匀，不易发生聚集，且能够进一步形成具有良好质构特性的乳液凝胶。

Abstract: In this study, rabbit myofibrillar protein (RMP) was extracted, and Pickering emulsion and the emulsion gel were prepared with soybean oil as the oil phase. The effects of different pH environment (3~10), carrageenan (0.25%~0.50%) and sodium alginate (0.25%~0.50%) on the stability and gel properties of Pickering emulsion were investigated, in order to prepare Pickering emulsion gel with high stability by using RMP. The results showed that when pH value was 9, the absolute value of ζ-potential of RMP emulsion was the largest (33.60 mV). The absolute value of ζ-potential (72.97±0.60), emulsifying activity index (EAI) (5.09±0.09 m²·g⁻¹) and emulsifying stability index (ESI) (46.07%±3.74%) of RMP-Pickering emulsion all reached the maximum value when the oil phase volume was 50% and the concentration of carrageenan and sodium alginate polysaccharide were both 0.35% at pH9. In the range of polysaccharide concentration from 0.25% to 0.35%, the water holding capacity, hardness and elasticity of RMP-Pickering emulsion gel with carrageenan and sodium alginate added all increased gradually, and these indicators reached the maximum value at the polysaccharide concentration of 0.35%. Besides, the sodium alginate-RMP Pickering emulsion gel had lower hardness and higher water holding capacity and elasticity than carrageenan-RMP gel, in the range of polysaccharide concentration from 0.35% to 0.50%. Infrared spectrum analysis showed that, with the increase of polysaccharide concentration, the content of β-folded of the RMP Pickering emulsion gel stabilized by the two polysaccharides increased first and then decreased, and the secondary structure of proteins changed from disordered to ordered. When both concentration of polysaccharides were 0.35%, the β-folded content reached the maximum (carrageenan group: 30.34%±0.04%, sodium alginate group: 29.70%±0.12%). According to analysis of macro and micro structures and gel force, hydrophobic interaction and disulfide bond both played a role in maintaining gel structure of carrageenan- and sodium alginate-RMP Pickering emulsion gel. In conclusion, when the final concentrations of carrageenan and sodium alginate were both 0.35%, the polysaccharides-RMP-Pickering emulsion system could be distributed more evenly, and aggregation was not easy to occur, and the emulsion gel with good texture characteristics could be further formed.