机械搅拌对凝胶状油脂质构、流变及微观形态的影响

Effect of Mechanical Stirring Rate on the Texture, Rheological Property and Microstructure of Gel-Like Oil

摘要:

以精炼一级大豆油(RBDSBO)加入体积分数5%全氢化棕榈硬脂(FHPST)制备凝胶状油脂,探讨了不同的机械搅拌速率(0~10 000 r/min)对凝胶状油脂质构、流变性质及微观形态的影响,同时探讨了其微观结构与物理特性的关系。实验结果表明:搅拌速率小于500 r/min时,样品的硬度、凝聚性,储能模量(G’)、损耗模量(G")及不规则碎片维数Db均随着搅拌速率的增大而增大,其中搅拌速率为0~200 r/min时增大最明显;但当搅拌速率大于500 r/min时,其质构、流变学等参数没有显著差异。因此,机械搅拌速率500 r/min时凝胶状油脂的网络强度、质构及流变等机械性质为最佳。

Abstract:

In this study,the effect of mechanical stirring rate on the texture,rheological properties and crystalline morphology of gel-like oil prepared by adding 5% fully hydrogenated palm stearine into soybean oil was investigated,and the relationship between the microstructure and the physical properties was also discussed.The following results were obtained:the firmness,the value of G′,G" and Db were enhanced by increasing the stirring rate from 0 to 500 r/min,especially within 0~200 r/min.However,high shear rate(>500 r/min) led to a lower G′ value.Optimal gel-like oil was formed when moderate shear rate of 500 r/min was applied.