Institute of Polymer Technology and Nanotechnology, University of Buenos Aires-CONICET, Faculty of Engineering, Las Heras 2214, C1127AAQ Ciudad de Buenos Aires, Argentina.
Institute of Crystallography, National Research Council, 122/O Amendola, I-70126 Bari, Italy.
Food Res Int. 2018 Mar;105:129-139. doi: 10.1016/j.foodres.2017.11.011. Epub 2017 Nov 14.
Films obtained by casting, starting from conventional emulsions (CE), nanoemulsions (NE) or their gels, which led to different structures, with the aim of explore the relationship between structure and physical properties, were prepared. Sodium caseinate was used as the matrix, glycerol as plasticizer, glucono-delta-lactone as acidulant to form the gels, and TiO nanoparticles as reinforcement to improve physical behavior. Structural characterization was performed by SAXS and WAXS (Small and Wide Angle X-ray Scattering, respectively), combined with confocal and scanning electron microscopy. The results demonstrate that the incorporation of the lipid phase does not notably modify the mechanical properties of the films compared to solution films. Films from NE were more stable against oil release than those from CE. Incorporation of TiO improved mechanical properties as measured by dynamical mechanical analysis (DMA) and uniaxial tensile tests. TiO macroscopic spatial distribution homogeneity and the nanostructure character of NE films were confirmed by mapping the q-dependent scattering intensity in scanning SAXS experiments. SAXS microscopies indicated a higher intrinsic homogeneity of NE films compared to CE films, independently of the TiO load. NE-films containing structures with smaller and more homogeneously distributed building blocks showed greater potential for food applications than the films prepared from sodium caseinate solutions, which are the best known films.
通过浇注获得的薄膜，起始于常规乳液（CE）、纳米乳液（NE）或它们的凝胶，这些乳液或凝胶形成了不同的结构，旨在探索结构与物理性质之间的关系。以酪蛋白酸钠作为基质，甘油作为增塑剂，葡萄糖酸-δ-内酯作为酸化剂形成凝胶，并加入 TiO 纳米颗粒作为增强剂来改善物理性能。通过小角和广角 X 射线散射（SAXS 和 WAXS）、共聚焦和扫描电子显微镜对结构进行了表征。结果表明，与溶液膜相比，脂质相的加入对膜的力学性能没有明显的影响。与 CE 相比，NE 形成的薄膜对油的释放更稳定。添加 TiO 提高了动态力学分析（DMA）和单轴拉伸试验所测量的力学性能。通过扫描 SAXS 实验中 q 相关散射强度的映射，证实了 TiO 的宏观空间分布均匀性和 NE 薄膜的纳米结构特征。SAXS 显微镜表明，与 CE 薄膜相比，NE 薄膜具有更高的固有均匀性，而与 TiO 的负载无关。与由酪蛋白酸钠溶液制备的薄膜相比，含有具有更小和更均匀分布的结构的 NE 薄膜在食品应用方面具有更大的潜力，而由酪蛋白酸钠溶液制备的薄膜是最知名的薄膜。
