采用溶剂替换法制备β-胡萝卜素纳米粒子,通过考察4种乳化剂对制备纳米粒子粒径及分布的影响和测定贮藏过程中粒子粒径和β-胡萝卜素含量变化,研究了其稳定性。试验结果表明:以酪蛋白钠为乳化剂制备的β-胡萝卜素纳米粒子粒径大于以Tween 20、蔗糖脂肪酸酯和月桂酸十甘油酯为乳化剂制备的纳米粒子;向蔗糖脂肪酸酯中添加酪蛋白钠,以此混合物作为乳化剂可以制备平均粒径小于50 nm的β-胡萝卜素纳米粒子;贮藏过程中,所有乳化剂制备的β-胡萝卜素纳米粒子粒径均保持较好的稳定性,β-胡萝卜素含量随着贮藏时间延长而减小,特别是在Tween 20为乳化剂制备的纳米粒子中降解最为明显。
Effect of four different emulsifiers on the physicochemical properties and stability of β--carotene nanoparticles in oil-in-water dispersions produced by a solvent displacement technique were examined. Theβ- in carotene particle size was measured, and the stability and retention of β--carotene during storage were determined by HPLC. The particle size ofβ--carotene nonodispersions stabilized by sodium caseinate (SC) was generally larger than that in the presence of Tween 20, sucrose fatty acid ester (SE) or decaglycerol monolaurate (ML750). The addition of SE or ML750 could increase the ability of sodium caseinate to stabilizeβ--carotene particle formation. It is suggested that sodium caseinate can be useful to partly replace SE as emulsifiers in the preparation ofβ--carotene nanodispersions with less than 50 nm mean diameter. During storage at 4℃, although the β--carotene content in the nanodispersions showed a significant decrease with increasing storage period, especially in the case of Tween 20 as emulsifiers, the size distribution was almost unchanged in all prepared β--carotene nanodispersions.