Abstract The objective of the work was to carry out a comprehensive study to investigate the tribological response of the oil-in-water (o/w) emulsion systems between polydimethylsiloxane disc and steel ball surface using a ball-on-disc tribology assembly (3 point-contact). Simultaneously, oral and finger tactile sensory measurements were recorded to predict ‘smoothness’, in order to establish a reliable correlation between instrumental characterization and human perception. We hypothesized that the lubrication behavior of emulsions (constant oil droplet size) with varying oil mass fractions stabilized by different emulsifiers influences smoothness perception. Different emulsifiers studied were whey protein isolate (pH 6.7 & pH 3.5), modified starch and lysozyme while oil mass fractions of 30, 20, 10, 5 and 1 w% were examined. In-vitro studies with simulated saliva were also performed on the tribometer. All the emulsions showed typical Stribeck curve patterns with clear boundary and the mixed regime, while, the hydrodynamic regime was observed for high oil mass fractions. Friction coefficient (CoF) for all the emulsions was significantly different at most of the oil mass fractions (P

中文翻译：

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作为触觉感知的平滑度：将“口腔”摩擦学与感官测量相关联

摘要 这项工作的目的是使用球对盘摩擦学组件 (3) 对聚二甲基硅氧烷盘和钢球表面之间的水包油 (o/w) 乳液体系的摩擦学响应进行全面研究。点接触）。同时，记录口腔和手指触觉感官测量以预测“平滑度”，以便在仪器表征和人类感知之间建立可靠的相关性。我们假设由不同乳化剂稳定的具有不同油质量分数的乳液（恒定油滴尺寸）的润滑行为会影响光滑度感知。研究的不同乳化剂是乳清蛋白分离物（pH 6.7 和 pH 3.5）、改性淀粉和溶菌酶，同时检查了 30、20、10、5 和 1 w% 的油质量分数。还在摩擦计上进行了模拟唾液的体外研究。所有乳液均表现出典型的 Stribeck 曲线模式，具有清晰的边界和混合状态，而对于高油质量分数则观察到流体动力学状态。所有乳液的摩擦系数（CoF）在大多数油质量分数（P