基于藜麦蛋白Pickering乳液模拟牛油

Simulation of Beef Tallow Based on Quinoa Protein-Stabilized Pickering Emulsion

以藜麦分离蛋白为界面颗粒、玉米油为分散相、牛骨汤或牛肉粉溶液为乳液连续相,使用高速剪切法制备藜麦蛋白Pickering高内相乳液,并对不同组乳液的流变学特性、热力学性质、颜色及挥发性物质进行分析。结果表明:5组乳液均表现出明显的假塑性流体剪切稀化行为,样品的表观黏度随着剪切速率的增加而降低,但是在相同的剪切速率下,在水相中添加鱼明胶的乳液黏度最高,更利于模拟牛油的黏稠感;在乳液水相中添加鱼明胶或淀粉明显增加了乳液的储能模量(G′)和损耗模量(G″),提高乳液的黏弹特性,且添加鱼明胶的藜麦蛋白乳液的黏弹特性优于添加淀粉的乳液,更接近牛油的流变特性;与纯牛骨汤为水相的乳液相比,在牛骨汤水相中添加鱼明胶可显著提高乳液的亮度和白度(P<0.05),而以牛肉粉溶液为水相会降低乳液的亮度和白度;添加淀粉和鱼明胶乳液水相可以明显提高藜麦蛋白Pickering乳液熔点;气相色谱-质谱测定结果表明,使用牛骨汤作为乳液的水相可以增加己醛、4-异丙基甲苯、十五烯等风味物质含量,使乳液具有部分牛油的风味,而以牛肉粉溶液为水相的乳液风味物质的种类与水相为牛骨汤的类似,但是其风味物质含量较低。综上所述,以牛骨汤添加鱼明胶作为乳液水相时,藜麦蛋白Pickering乳液表现出更接近牛油的流变学性质、外观及较高熔点,并具有类似牛油的挥发性风味物质,在模拟饱和脂肪方面具有潜力和持续研究价值。

In this study,high-internal phase Pickering emulsions(HIPPEs)were prepared by high speed shearing using quinoa protein isolate(QPI)as interfacial particles,corn oil as dispersed phase,and beef bone broth or beef powder solution as continuous phase,and their rheological properties,thermodynamic properties,color and volatile components were analyzed.The results showed that all 5 emulsions exhibited obvious shear thinning behavior of a pseudoplastic fluid,and their apparent viscosities decreased with the increase in shear rate.However,at the same shear rate,the emulsion with fish gelatin added to the aqueous phase showed the highest viscosity,which was more conducive to simulating the sticky taste of beef tallow.Addition of fish gelatin or starch into the aqueous phase significantly increased the storage modulus(G′),loss modulus(G″)and viscoelastic properties of Pickering emulsions,and the emulsion with fish gelatin had better viscoelastic properties and rheological properties closer to those of beef tallow than the emulsion with starch.Adding fish gelatin to the aqueous phase containing beef bone broth significantly increased the brightness and whiteness of Pickering emulsion(P<0.05),whereas the opposite effect was observed when the aqueous phase was beef powder solution.Moreover,adding starch or fish gelatin into the aqueous phase could significantly increase the melting point of quinoa protein-stabilized Pickering emulsion.The results of gas chromatography-mass spectrometry(GC-MS)showed that using beef bone broth as the aqueous phase increased the contents of flavor components such as hexanal,4-isopropyl toluene,and pentadecylene,imparting the emulsion with part of the flavor of beef tallow.The composition of flavor components in the emulsion with beef powder solution was similar to that in the emulsion with beef bone broth,but the content of flavor compounds was lower in the emulsion with beef powder solution than with beef bone broth.In summary,quinoa protein-stabilized Pickering emulsion with an aqueous phase containing bovine bone broth and fish gelatin showed similar rheological properties,appearance and volatile flavor composition to beef tallow,and it possessed higher melting point,showing its potential and sustained research value in simulating saturated fat.