在低剪切速率下,采用AR-500流变仪测定了不同压力下蛋黄酱的流变特性,结果表明,高压处理后的蛋黄酱是剪切稀化流体,具有假塑性特征.利用已知非牛顿流体本构方程对测量值进行曲线拟合的方法,以标准差最小作为最佳拟合,得到了不同高压处理条件下蛋黄酱的数学模型,并初步分析了粘度随压力变化的原因.在500 MPa范围内,超高压处理使得蛋白质分子发生了一定程度的解聚、伸展;超过500 MPa以后,虽然可能造成蛋白质颗粒的进一步解聚和伸展,但解聚的小分子又可能部分重新缔合,而且此时蛋黄酱中的油滴颗粒也会增大,使得由于颗粒间滑移和摩擦而耗散的能量减少.%The rheological property of mayonnaise under different pressures is measured using AR-500 rheometer at low shear rate. The results show that Mayonnaise processed by high pressure is shear thinning fluid and takes on pseudoplastic characteristics. Taking the minimum standard error as the standard for best fit, the mathematic model of mayonnaise under different high pressure processing is obtained by using the constitutive equation of non-Newtonian flow and measured data to fit curves, and the reason of viscosity variety in terms of pressure is analyzed tentatively. This is due to the protein molecule disassociated and unfolded with treatment of less than or equal to 500 MPa, while small molecule disassociated with the continuous increase of pressure may be associated over again, and increase of salad oil particle size in mayonnaise results in decrease of energy dissipation using slippage and friction beyond 500 MPa.
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