Relating rheological measurements to primary and secondary skin feeling when mineral‐based and Fischer–Tropsch wax‐based cosmetic emulsions and jellies are applied to the skin

Rheology measurements were correlated to skin sensations occurring when cream and petroleum jelly cosmetic products containing different amounts of synthetic Fischer–Tropsch wax were applied to the skin. A panel of 15 people with a background in cosmetic product development were asked to rate skin feelings when a range of petroleum jelly and cream samples are applied to the skin. Primary skin feel, or the spreadability of a cosmetic product, was correlated to the product's flow onset and maximum viscosity as measured by a Anton Paar rheometer, whereas secondary skin feel or the sensation occurring at the end of application when the product was completely rubbed into the skin was correlated to the product's viscosity measured at high shear rates. The cream samples prepared with a petroleum jelly containing 10% and 20% Fischer–Tropsch wax fell within the boundary of good primary skin feeling of cream products. Predominantly, synthetic petroleum jellies were given the best assessments in terms of primary skin feeling and were used with mineral‐based petroleum jellies to determine the boundary of good primary skin feeling for petroleum jelly products. The further away a product falls from this rheological boundary the poorer the skin feeling assessment appears to be by the panel. Products containing Fischer–Tropsch waxes were given the best assessment by the panel for secondary skin feeling. Comments from the panel include that these products feel silky and light on the skin. The higher the Fischer–Tropsch wax content, the lower viscosity was at high shear rate (? = 500 s^?1) and the higher the assessment by the panel. Rheological measurements can be used to objectively determine skin sensation when products are applied to the skin; this may shorten research and development times. A rheology boundary of certain product viscosity and shear stress applied is associated with good primary skin feeling for lotions, creams and petroleum jellies. Lower product viscosity at high shear rate seems to be associated with better secondary skin feeling. Products with higher Fischer–Tropsch wax content appear to be rated higher in terms of secondary skin feeling.     

12种杂粮米及其混合米感官评价分析

以12种杂粮米为原料,浸泡处理后进行蒸煮。蒸煮后,采用质构仪分析测定各种杂粮米的硬度等力学特性。根据各种杂粮的硬度将12种杂粮米分成7组,各组杂粮米按1:1混合并蒸煮,然后进行感官评价,选出最佳的混合方案。结果表明:紫大米和白大米混合蒸煮的产品最佳,绿大米、黑大米、玉米碴(小)的混合蒸煮口味最差。     

基于模糊感官评价对大米感官品质分析

以7种不同品种的大米为研究对象,运用模糊综合评判法评价大米感官品质,用质构仪及色差仪对米饭品质进行评定。结果表明:大粒香米饭感官品质最佳,内优5H25最差,米饭质构特性中内优5H25米饭弹性和咀嚼性最大,大粒溪香、大粒香、金麻粘3种米饭在粘硬度比、粘性、弹性均无显著差异,且大粒香3项指标值均最大,说明大粒香质构特性最佳。不同品种米饭色差值存在显著差异。结合感官评价中对米饭色泽要求综合分析色差值,大粒香和金麻粘色泽最佳。模糊感官评价与外观品质特性和质构特性结果相一致,综合分析表明:大粒香米饭感官品质最佳,说明模糊感官评价能有效的评价米饭感官品质。      

Rheological changes during thermal processing of low-fat meat emulsions formulated with different texture-modifying ingredients

The rheological behaviour of high-fat (22%) and low-fat (8%) meat emulsions during thermal processing in the presence (3%) of various texture-modifying non-meat ingredients, namely maltodextrin, starch, wheat flour, egg white and apple fibre, was analysed. Rheological properties of emulsions were assessed using non-destructive measurements (thermal scanning rigidity monitor, TSRM). The lower the fat content, the lower were the rigidity values of meat emulsions throughout the temperature range studied. Emulsions made with maltodextrin proved less rigid. Addition of starch and egg white favoured the formation of more rigid structures in low-fat meat emulsions at temperatures over 55 °C. Low-fat meat batters containing wheat flour and apple fibre exhibited the highest rigidity values over the given temperature range. The presence of wheat flour caused variations in the modulus of rigidity at all stages of the thermal gelation process, very similar to those observed in high-fat emulsions.