Glycerin is produced during soap manufacturing and has several valuable properties in skin care products. Firstly it is a humectant, which means that it helps to retain moisture in creams and lotions. This property has been recognised for centuries and glycerin was a key ingredient in the earliest known hand creams.
Secondly, glycerin is an emollient, which means it makes the skin feel softer and smoother and helps to reduce wrinkles. This is achieved partly through coating the shin with a thin layer of oily wax, and partly by reducing water loss from the skin.
Glycerin is also a solvent that extracts active ingredients from many plant materials through glycerol refining equipment and can also help to mix together many different ingredients used in creams and lotions.