Essential oils are plant secondary metabolites in plants, from a relatively small molecular weight compounds composed of simple, has a certain aroma, can be volatile at room temperature, the oil-like liquid substance. Chemical composition of essential oils contained in the complex, according to their chemical structure can be divided into aliphatic, aromatic and terpene three oxygen compounds and their derivatives such as alcohols, aldehydes, ketones, acids, ethers, esters, lactones, etc., in addition to nitrogen and sulfur compounds, and these compounds have low boiling point volatile characteristics. Essential oils of plants are more abundant Cupressaceae, Magnoliaceae, Lauraceae, umbelliferous, lip spend Branch, Asteraceae, Rutaceae, the ginger family, Myrtaceae, Dipterocarpaceae and grass and so on. Preparation of essential oils in plants based on natural flowers, leaves, branches, roots, bark, gum, whole plant and fruit as raw materials by steam distillation, pressing, absorption, solvent extraction and supercritical carbon dioxide extraction other methods from the system. Early scientists study the chemical constituents of essential oils is limited to a few higher levels of ingredients, along with the application of capillary gas chromatography and improve more and more in-depth study of essential oils. An essential oil can be identified dozens, even hundreds of chemical components, some of the content of the ingredients have been little identified. This is the depth of oil development and natural resources to find spices, aromatic plant breeding of fine varieties are of great significance. Typically, essential oils are used to prepare flavor, fragrance, but with the rapid increase of people's quality of life and environmental awareness continues to strengthen the application of plant extracts essential oils have gradually expanded. Essential oils in food additives, pest control, sterilization and other aspects of anti-bacterial and anti-corrosion features, but also become an increasing concern and attention.
As people's living standards and consumption levels increase, people's own health and health care concerns more and more intense consciousness, especially in food processing, more and more to "green" and "natural" direction of change. Preservatives is an important additive in the food industry, one of the world's food industry to chemical preservative commonly used in the majority of synthetic preservatives, synthetic preservatives and chemical induced cancer, teratogenesis and ease of chronic poisoning caused by food and other issues has aroused widespread concern in society. Therefore, natural, safe functional food research and development of preservatives is becoming increasingly important. People started to pay attention the safety of food additives, natural food additive and thus have high hopes for the development of natural nutrition is a multi-functional food additives food industry development. One of the essential oils are a class of natural plant additives, the smell of food can be corrected, giving the aroma, and some are colored, resveratrol antioxidant, antimicrobial (antiseptic) and the physiological and pharmacological effects. As an important source of natural preservatives, essential oils from plants screened and efficient, economical and safe anti-corrosion material as a food preservative, has broad application prospects. In foods such as cinnamon oil as a natural food spices widely used, involving almost all aspects, mainly for soft drinks, candy, canned food, baked goods, alcohol and tobacco and so on. In beverages, meat and spices, allowing dosage of 300,290 and l0O mg / kg, and in the gum in the amount of up to 1900mg/kg. In addition, cinnamon oil, fruit and pastries can also be used for food preservation. Although many essential oils have been included in the harmless components or approved as food additives, spices, but some studies have shown that some of them have some kind of irritating and toxic ingredients. Some essential oils or their frequent use of single-component, will lead to allergic dermatitis.
Essential oils aromatherapy bath to promote good physical and mental health effects, the different functions of various essential oils, aromatherapy bubble bath often can promote blood circulation, balance the endocrine, speed up metabolism, prevent skin aging, moisturizing, soothing mood, Slimming and so on. Drugs in many countries with oil, "USP", "British Pharmacopoeia", "French Pharmacopoeia", "German Pharmacopoeia", "Japanese Pharmacopoeia" and "European Pharmacopoeia" in both oil-related discussion. Been refined, such as volatile oil menthol, camphor, eugenol, eucalyptus oil, garlic oil and other pharmaceutical raw materials directly used as a pharmaceutical. With divergent relieving essential oils, aromatic resuscitation, qi pain, anti-bacterial, anti-virus and other pharmacological effects. Such as peppermint oil carminative stomachic, wintergreen oil analgesic, antipyretic Bupleurum oil, oil of Chenopodium ambrosioides and other anthelmintics. In recent years, also found that garlic contains volatile allicin (garlic oil), is a plant-derived broad-spectrum antibiotics. Source:http://www.cospcn.com