Ebooks doTERRA Essential Oil Chemistry Handbook | Page 13

Chapter 1: An Introduction to Essential Oils CHAPTER 1: AN INTRODUCTION TO ESSENTIAL OILS 1.1 WHAT ARE ESSENTIAL OILS? Essential oils are called “essential” because they are the “essence” of a plant. In the Middle Ages, it was believed that essential oils were essential for life, giving them the moniker that has stuck even to the present day. Modern references define an essential oil as the essence, or extract, that is the source of a plant’s aroma and flavor. For example, peppermint plants smell like peppermint because of the essential oil contained in their leaves and stems. Oranges smell like oranges because of the essential oil contained in the peel. Why do plants produce essential oils? Essential oils are a critical part of a plant’s immune system. Plants produce essential oils to protect themselves against environmental threats. The parts of a plant with the greatest amount of essential oil are usually the parts with the greatest risk for invasion by microorganisms: the bark, sap, leaves, seeds, and fruit rinds. The compounds found in essential oils have all sorts of biological activities. They are known to protect against environmental threats, soothe the body, and even calm the mind. 1.2 OBTAINING ESSENTIAL OILS FROM PLANT PARTS While it is important to note that essential oil extraction is unique to every plant, in general, dōTERRA essential oils are extracted using one of three methods: steam distillation, cold press, or solvent extraction. Steam Distillation is the most common method for collecting essential oils. In steam distillation, water is boiled and the resulting steam passes through the plant material. The steam carries the essential oil from the plant into a collecting tube, where the steam is cooled and condensed back into water. Because essential oils are lipid soluble (meaning that they mix readily with other oils), they are   3