二次均质处理对UHT搅打稀奶油品质的影响

Effect of Secondary Homogenization on the Quality of Ultra-High Temperature Sterilized Whipped Cream

系统地分析不同二次均质压力对经过超高温瞬时杀菌(ultra-high temperature instantaneous sterilization,UHT)处理后的搅打稀奶油品质的影响。结果表明,在4~8 MPa压力条件下对稀奶油进行二次均质可使乳液粒径向小颗粒方向偏移,并同时增加表观黏度,从而提高乳液稳定性。然而,过高的均质压力会导致乳液内部出现脂肪聚结现象,影响稀奶油的表观黏度和泡沫稳定性。随着二次均质压力的增大,稀奶油出现打发时间延长,打发率、泡沫稳定性下降以及泡沫硬度降低等问题,甚至在12 MPa时已无法打发成型。因此建议将二次均质压力控制在4~6 MPa。

In this research,the effect of different secondary homogenization pressures on the quality of ultra-high temperature instantaneous sterilized(UHT)whipped cream was analyzed.The results showed that secondary homogenization of whipped cream at pressures ranging from 4 to 8 MPa shifted the size distribution of the emulsion droplets toward smaller values,and increased the apparent viscosity,which improved the stability of the emulsion.However,too high homogenization pressure led to fat aggregation within the emulsion droplets,affecting the apparent viscosity and foam stability of whipped cream.With an increase in secondary homogenization pressure,whipping time of whipped cream was prolonged,whipping rate,foam stability and hardness was decreased,and even at 12 MPa,it could not be whipped into shape.Therefore,it is recommended that the secondary homogenizing pressure be controlled in the range of 4 to 6 MPa.