南瓜籽油乳液的制备及稳定性

采用高压均质法，以乳清分离蛋白为乳化剂制备南瓜籽油乳液，对均质压力、均质次数、乳化剂添加量以及南瓜籽油质量分数对南瓜籽油乳液粒径、多分散系数（PDI）、Zeta电位和分光比（SRI,800 nm下吸光度与400 nm下吸光度的比值）的影响进行考察，并研究了南瓜籽油乳液的稳定性。结果表明：南瓜籽油乳液的最佳制备工艺条件为均质压力50 MPa、均质次数5次、乳化剂添加量2.5%、南瓜籽油质量分数10%，在最佳工艺条件下，南瓜籽油乳液的粒径为（213.33±5.60）nm，PDI 为0.215±0.002，Zeta电位为（-5680±0.66）mV，SRI为 0.27±0.02；在15 d的室温储藏期间内南瓜籽油乳液具有较好的物理稳定性和较高的氧化稳定性。

Stability and preparation of pumpkin seed oil emulsion

The high-pressure homogenization method was used to prepare pumpkin seed oil emulsion with whey protein isolate as emulsifier. The effects of homogenization pressure, homogenization times, dosage of emulsifier, and mass fraction of pumpkin seed oil on the particle size, polydispersity index (PDI), Zeta potential and spectral ratio (SRI, ratio of absorbance at 800 nm to absorbance at 400 nm) of pumpkin seed oil emulsion were investigated. The stability of pumpkin seed oil emulsion was also studied. The results showed that the optimal process conditions of pumpkin seed oil emulsion were obtained as follows: homogenization pressure 50 MPa, homogenization times five times, dosage of emulsifier 2.5%, mass fraction of pumpkin seed oil 10%. Under these conditions, the particle size, PDI, Zeta potential and SRI of pumpkin seed oil emulsion were (213.33±5.60)nm, 0.215±0.002, (-56.80±0.66)mV and 0.27±0.02,respectively. Pumpkin seed oil emulsion had better physical stability and higher oxidation stability during the storage period of 15 d at room temperature.