Milk Science Institute, Megmilk Snow Brand, Co., Ltd.
Graduate School of Life Science, University of Hyogo.
J Oleo Sci. 2021 Apr 2;70(4):479-490. doi: 10.5650/jos.ess20210. Epub 2021 Mar 10.
The effects of sucrose ester of fatty acid (SEF) on the nanostructure and the physical properties of water-in-oil (W/O)-type emulsified semisolid fats were investigated. Model emulsions including palm-based semisolid fats and fully hydrogenated rapeseed oils with 0.5% SEF or fractionated lecithin, were prepared by rapidly cooling crystallization using 0.5% monoacylglycerol as an emulsifier. The SEFs used in this study were functionalized with various fatty acids, namely, lauric, palmitic, stearic, oleic, and erucic acids. Cryogenic transmission electron microscopy (cryo-TEM) was used to observe the sizes of the solvent- extracted nanoplatelets. The solid fat content (SFC), oil migration value, and storage elastic modulus were also determined. The average crystal size, which was measured in length, of the fat blends with SEFs containing saturated fatty acids (namely, palmitic and stearic acids) was smaller than that of the SEFs containing unsaturated fatty acids (namely, oleic and erucic acids). The effects exerted by these fatty acid moieties on the spherulite size in the corresponding bulk fat blends were observed via polarized microscopy (PLM). The results suggest that nanostructure formation upon the addition of SEF ultimately influenced these aggregated microstructures. Generally, smaller platelets resulted in higher SFC in the fat phase, and a high correlation between the SFC and the G' values in W/O emulsion fats was observed (R = 0.884) at 30°C. In contrast, the correlation was low at 10℃. Furthermore, samples with larger nanocrystals had a higher propensity for oil migration. Thus, the addition of SEF regulated the fat crystal nanostructure during nucleation and crystal growth, which could ultimately influence the physical properties of commercially manufactured fat products such as margarine.
研究了脂肪酸蔗糖酯（SEF）对油包水乳状半固体脂肪的纳米结构和物理性质的影响。通过使用 0.5%单甘油脂作为乳化剂快速冷却结晶，制备了包括棕榈基半固体脂肪和完全氢化菜籽油在内的模型乳液，其中添加了 0.5%的 SEF 或分馏卵磷脂。本研究中使用的 SEF 用各种脂肪酸进行了功能化，即月桂酸、棕榈酸、硬脂酸、油酸和芥酸。使用低温透射电子显微镜（cryo-TEM）观察溶剂提取纳米薄片的尺寸。还测定了固脂含量（SFC）、油迁移值和储存弹性模量。含有饱和脂肪酸（即棕榈酸和硬脂酸）的脂肪混合物中 SEF 的平均晶体尺寸（按长度测量）小于含有不饱和脂肪酸（即油酸和芥酸）的 SEF。通过偏光显微镜（PLM）观察了这些脂肪酸基团对相应块状脂肪混合物中球晶大小的影响。结果表明，添加 SEF 后纳米结构的形成最终影响了这些聚集的微观结构。通常，较小的薄片会导致脂肪相中更高的 SFC，并且在 30°C 时，在 W/O 乳液脂肪中 SFC 与 G'值之间存在高度相关性（R=0.884）。相比之下，在 10°C 时相关性较低。此外，具有较大纳米晶体的样品具有更高的油迁移倾向。因此，SEF 的添加调节了脂肪晶体在成核和晶体生长过程中的纳米结构，这最终可能会影响商业制造的脂肪产品（如人造黄油）的物理性质。
