Wintergreen originally came from a small perennial herb native to the North Eastern portions of the United States. According the the Canadian Forestry Association quoted below, it was the original source of the active ingredient in Aspirin. People’s in North America, prior to the arrival of Europeans, brewed a tea from it and used it to treat a variety of symptoms, from respiratory infections to headaches. When tea became scarce during the North American Colonists’ rebellion against England, they adopted the practices of the Native Americans and brewed an infusion from it. With it’s delicious flavor and variety of therapeutic uses, Wintergreen eventually found its way into the originally medicinal elixirs which we now call Sarsaparilla and Root Beer.
As noted below, Wintergreen Oil and Sweet Birch Oil are essentially identical chemically, so if you’re using one, you probably don’t need to use the other in your Root Beer, especially since it seems to be pretty impossible to find sweet birch bark available commercially. If you’ve got a Sweet Birch (Betula lenta) in your backyard, give making it from scratch a try and let me know how it works out.
Wintergreen entry from Your Local Wildwood Pharmacy, Canadian Forestry Association website.
“It is as a medicinal herb that wintergreen is best known. Oil of wintergreen, distilled from the leaves, is composed primarily of methyl salicylate, a poison if used in large quantities. Minute amounts of this oil are used in flavouring toothpaste and other dental products, candy and lozenges. Aspirin, the most widely used drug after tobacco and caffeine, was originality extracted from wintergreen. When the poison (methyl) is removed from the oil, the crystalline material left behind is acetylsalicylic acid, the effective ingredient in aspirin.
“As well as oil, the leaves of wintergreen contain a compound called arbutin. This material is more stable when it is heated than when it is cold, meaning that it retains its medicinal qualities when heated or rubbed into muscles for treating various aches and pains including rheumatism. A few drops of wintergreen oil on a soft cloth and placed on the brow is a common time-proven cure for headaches. As well, the stems of the plant are chewed by people around the world to prevent tooth decay.”
Wintergreen entry from A Modern Herbal, by M. Greive, circa 1900.
“Botanical: Gaultheria procumbens (LINN.)
“—Synonyms—Teaberry. Boxberry. Mountain Tea. Checkerberry. Thé du Canada. Aromatic Wintergreen. Partridge Berry. Deerberry.
“—Habitat—Northern United States from Georgia to Newfoundland; Canada.
“—Description—A small indigenous shrubby, creeping, evergreen plant, growing about 5 to 6 inches high under trees and shrubs, particularly under evergreens such as Kalmias and Rhododendrons. It is found in large patches on sandy and barren plains, also on mountainous tracts. The stiff branches bear at their summit tufts of leaves which are petiolate, oval, shiny, coriaceous, the upper side bright green, paler underneath. The drooping white flowers are produced singly from the base of the leaves in June and July, followed by fleshy, bright red berries (with a sweetish taste and peculiar flavour), formed by the enlargement of the calyx. The leaves were formerly official in the United States Pharmacopoeia, but now only the oil obtained from them is official, though in some parts the whole plant is used. The odour is peculiar and aromatic, and the taste of the whole plant astringent, the leaves being particularly so.
“—Constituents—The volatile oil obtained by distillation and to which all the medicinal qualities are due, contains 99 per cent Methyl Salicylate: other properties are 0.3 of a hydrocarbon, Gaultherilene, and an aldehyde or ketone, a secondary alcohol and an ester. To the alcohol and ester are due the characteristic odour of the oil. The oil does not occur crudely in the plant, but as a nonodorous glucoside, and before distillation, the leaves have to be steeped for twelve to twenty-four hours for the oil to develop by fermentation – a reaction between water and a neutral principle: Gaultherin.
“—Medicinal Action and Uses—Tonic, stimulant, astringent, aromatic. Useful as a diuretic and emmenagogue and for chronic mucous discharges. Is said to be a good galactogogue. The oil of Gaultheria is its most important product. It has all the properties of the salicylates and therefore is most beneficial in acute rheumatism, but must be given internally in capsules, owing to its pungency, death from inflammation of the stomach having been known to result from frequent and large doses of it. It is readily absorbed by the skin, but is liable to give rise to an eruption, so it is advisable to use for external application the synthetic oil of Wintergreen, Methyl Salicylate, or oil from the bark of Betula lenta, which is almost identical with oil of Gaultheria. In this form, it is a very valuable external application for rheumatic affections in all chronic forms of joint and muscular troubles, lumbago, sciatica, etc. The leaves have found use as a substitute for tea and as a flavouring for genuine tea. The berries form a winter food for animals, partridges, deer, etc. They have been used, steeped in brandy, to produce a bitter tonic taken in small quantities. The oil is a flavouring agent for tooth powders, liquid dentifrices, pastes, etc., especially if combined with menthol and eucalyptus.”