Nejatian Mohammad, Abbasi Soleiman
Food Colloids and Rheology Lab., Department of Food Science & Technology, Faculty of Agriculture, Tarbiat Modares University P O Box 14115-336 Tehran Iran
RSC Adv. 2019 Sep 10;9(49):28330-28344. doi: 10.1039/c9ra04761a. eCollection 2019 Sep 9.
The fabrication of concentrated nanoemulsions provides potential advantages such as loading capacity enhancement, storage and transportation costs reduction, and creation of novel textures. The current study investigated the capability of high power ultrasound on nanoemulsification of high concentration triglyceride using various natural emulsifiers (saponin, whey protein isolate, lecithin and sucrose monopalmitate). The impact of the emulsifier concentration (up to 6 wt%), oil content (up to 60 wt%) and exposure to sonication (up to 33 min) on the droplet size distribution, physical stability and rheological properties were evaluated. Regarding the dilute nanoemulsion (10 wt% oil), droplet size was inversely correlated with the concentration of emulsifiers, however only by using saponin (2 wt%) the droplet size was in nano range ( < 200 nm). The concentrated nanoemulsions (20-50 wt%) were also fabricated under sonication (15 min at saponin-to-oil ratio 2 : 10 w/w%). They also presented shear-thinning behavior with relatively low consistency coefficients. Surprisingly, the one with 60 wt% oil was easily converted to viscoelastic gel upon 3 min sonication. Owing to such characteristics, they could have potential applicability in formulation of soft foods, creams, sauces, salad dressings, pastes, lotions, cosmetics and pharmaceuticals.
浓缩纳米乳液的制备具有诸多潜在优势，如提高负载能力、降低储存和运输成本以及创造新颖质地。本研究考察了高功率超声对使用各种天然乳化剂（皂苷、乳清蛋白分离物、卵磷脂和蔗糖单棕榈酸酯）制备高浓度甘油三酯纳米乳液的能力。评估了乳化剂浓度（高达6 wt%）、油含量（高达60 wt%）和超声处理时间（长达33分钟）对液滴尺寸分布、物理稳定性和流变学性质的影响。对于稀纳米乳液（10 wt%油），液滴尺寸与乳化剂浓度呈负相关，但仅使用2 wt%的皂苷时液滴尺寸才处于纳米范围（<200 nm）。在超声处理（皂苷与油的比例为2 : 10 w/w%时处理15分钟）下也制备了浓缩纳米乳液（20 - 50 wt%）。它们还呈现出具有相对较低稠度系数的剪切变稀行为。令人惊讶的是，含60 wt%油的纳米乳液在超声处理3分钟后很容易转变为粘弹性凝胶。由于这些特性，它们在软食品、乳膏、酱汁、沙拉酱、糊剂、洗剂、化妆品和药物制剂中可能具有潜在的适用性。
