Riquelme N, Robert P, Troncoso E, Arancibia C
Departamento de Ciencia y Tecnología de los Alimentos, Facultad Tecnológica, Universidad de Santiago de Chile, Obispo Umaña 050, Estación Central, Chile.
Food Funct. 2020 Jul 1;11(7):5955-5964. doi: 10.1039/d0fo01202e.
Hydrocolloids are used as stabilizing agents in order to enhance the physical stability of emulsions during their storage. However, they can also play an important role in nutrient release and bioavailability. In this context, the aim of this research was to study the effect of the emulsion type and thickener type on the physical-structural changes and free fatty acid release during in vitro digestion. Oil-in-water emulsions were prepared with different particle sizes (CE: conventional emulsions and NE: nanoemulsions) and thickening agents (starch and xanthan gum). The experimental conditions of homogenization used allowed food emulsions to be obtained at the microscale and nanoscale, with particle sizes ranging among 3.2-3.4 μm and 78-107 nm for CE and NE, respectively. The addition of thickening agents (XG and ST) modified the physical properties of emulsions (particle size, zeta potential and stability) slightly, and thickened samples with similar viscosity were obtained. The kinetics of FFAs released during the in vitro intestinal digestion showed no significant differences (p > 0.05) in the digestion rate among samples; however, emulsion and thickener types decreased the final extent of free fatty acids, being more evident for those samples with starch. Xanthan gum kept the particle size of nanoemulsions stable during the oral and gastric phases, which promoted the release of FFAs during the intestinal phase. Therefore, xanthan gum could be used as a thickening agent of nanoemulsions exerting a minor impact on their lipid bioaccessibility.
水胶体被用作稳定剂，以提高乳液在储存期间的物理稳定性。然而，它们在营养物质释放和生物利用度方面也能发挥重要作用。在此背景下，本研究的目的是研究乳液类型和增稠剂类型对体外消化过程中物理结构变化和游离脂肪酸释放的影响。制备了具有不同粒径的水包油乳液（CE：常规乳液和NE：纳米乳液）以及增稠剂（淀粉和黄原胶）。所采用的均质化实验条件使得能够获得微米级和纳米级的食品乳液，CE和NE的粒径分别在3.2 - 3.4μm和78 - 107nm范围内。增稠剂（XG和ST）的添加略微改变了乳液的物理性质（粒径、zeta电位和稳定性），并获得了具有相似粘度的增稠样品。体外肠道消化过程中游离脂肪酸释放的动力学表明，各样品之间的消化速率没有显著差异（p > 0.05）；然而，乳液和增稠剂类型降低了游离脂肪酸的最终释放程度，对于含有淀粉的样品更为明显。黄原胶在口腔和胃阶段保持纳米乳液的粒径稳定，这促进了肠道阶段游离脂肪酸的释放。因此，黄原胶可作为纳米乳液的增稠剂，对其脂质生物可及性影响较小。
