Hydrolates are co-products in the process of distillation of herbal material used for making ethereal oils. This process leads to two complementary products: ethereal oil and hydrolate. Ethereal oil is a non-watersoluble component which is left over after the process of steam distillation. The remaining „water“ is a hydrolat. Hidrolat contains water-soluble components of the plant and small quantities of sprinkled ethereal oil.