EARLY UTILIZATION OF SOY IN TOPICAL APPLICATION For many years, due to the lack of basic research in understanding the fundamental mechanisms of soy on skin, soy’s nutritional components were used mainly as functional ingredients in the cosmetic industry (20) and mostly have remained so until today. The most frequently used soy components include soybean oil, soy protein isolates, and soy lecithin as shown in Table 11.1. Soybean oil is one of the valuable materials used to adjust the rheology of cosmetic emulsions. Examples of soy oil as an emollient and moisturizer include baby oil and moisturizing lotion. Soy protein isolate/hydrolysate has been formulated as an emulsi‘er and foaming enhancer into a wide variety of products, including laundry detergent, bath products, shampoos, and skin cleansers (21). The lecithin fraction of crude soybean oil has found application as an emulsifying, surface active agent, and a stabilizing agent in industrial products such as paint, ink, soap, and cosmetics (22). Soy sterols are employed as skin conditioners for lotion, creams, and cleansers (23).