Abstract:

The sensory experience and efficacy of cosmetics during use are prone to the influence of ambient temperature and humidity. This study focuses on emollient creams and lotions, examining changes in their sensory attributes and moisturizing efficacy under conditions of -5 ℃ with 40% relative humidity and 35 ℃ with 80% relative humidity. It delves into how different environments impact cosmetic sensory indicators. Results indicate that temperature and humidity variations significantly alter sensory properties such as gloss and firmness. In low temperature and low humidity settings, products exhibit greater firmness and peak height but show reduced spreadability and absorption. Conversely, in high temperature and high humidity conditions, products become softer in texture, with enhanced spreadability but increased heaviness. The study further probes into the impact of temperature and humidity on the moisturizing efficacy of creams and lotions. Through measurements of skin moisture content and transepidermal water loss, it is found that the product demonstrates significant moisturizing effects in environments at -5 ℃ with 40% relative humidity （p<0.05）, but no notable moisturizing function in settings at 35 ℃ with 80% relative humidity （p>0.05）. These findings offer a scientific reference for formulation design and selection during the development phase of cream and lotion cosmetics, and it is recommended that consumers adjust their product choices or storage conditions according to environmental differences. Currently, research on the correlation between some cosmetic sensory and efficacy attributes and temperature and humidity parameters remains inadequate. Future studies should center on the disparities in sensory and efficacy experiences of cosmetics used by different consumers in diverse climatic conditions.

Key words: moisturizing, cosmetics, human efficacy evaluation, sensory evaluation, temperature, humidity