Abstract:
Designing nutritious food for the elderly population often requires significant quantities of leucine-rich whey proteins to combat malnutrition, yet high-protein formulations can cause mouth dryness and increased oral friction. This study investigated how various colloidal processing methods and compositions impact the in vitro oral tribological properties of protein-rich emulsions and emulsion-filled gels. Oil-in-water emulsions with oil fractions from 1 wt% to 20 wt% were prepared, alongside emulsion-filled gels containing whey protein isolate (WPI), hydrolysed whey protein (HWP), or a blend of both (10 wt% protein content). Two processing approaches were employed: creating emulsions with an initial 10 w% protein content (M1) and initially forming emulsions with 0.1 wt% protein content, then enriching to a final 10 wt% concentration (M2). The hypothesis was that formulations with HWP or method 2 (M2) would offer lubrication benefits by inducing droplet coalescence, aiding in the formation of a lubricating boundary tribofilm. Surprisingly, the tribological behavior of high-protein emulsions showed minimal dependence on oil droplet volume fraction. However, both HWP-based emulsions and those processed with M2 for WPI exhibited significant friction reduction, which may be attributed to the presence of coalesced oil droplets, supporting our hypothesis. Substituting 50 wt% of WPI with HWP in emulsion-filled gel boli resulted in very low friction coefficients in the boundary lubrication regime, suggesting oil droplet release from the gel matrix. These findings provide insights into designing high-protein foods with improved mouthfeel for the elderly population, necessitating further validation through sensory studies.
摘要:
为老年人设计营养食品通常需要大量富含亮氨酸的乳清蛋白来对抗营养不良,然而,高蛋白配方会导致口腔干燥和口腔摩擦增加。这项研究调查了各种胶体加工方法和组合物如何影响富含蛋白质的乳液和乳液填充的凝胶的体外口腔摩擦学特性。制备具有1重量%至20重量%的油馏分的水包油乳液,与含有乳清蛋白分离物(WPI)的乳液填充凝胶一起,水解乳清蛋白(HWP),或两者的共混物(10重量%蛋白质含量)。采用了两种处理方法:产生具有初始10重量%蛋白质含量(M1)的乳液,并最初形成具有0.1重量%蛋白质含量的乳液,然后富集至最终10重量%浓度(M2)。假设是HWP或方法2(M2)的配方将通过诱导液滴聚结来提供润滑益处,有助于形成润滑边界摩擦膜。令人惊讶的是,高蛋白乳液的摩擦学行为对油滴体积分数的依赖性最小。然而,基于HWP的乳液和用于WPI的M2处理的乳液均表现出显着的摩擦降低,这可能归因于聚结的油滴的存在,支持我们的假设。在乳液填充的凝胶囊中用HWP代替50wt%的WPI导致边界润滑状态下的摩擦系数非常低,表明油滴从凝胶基质中释放。这些发现提供了为老年人设计改善口感的高蛋白食品的见解,需要通过感官研究进一步验证。