How-To Make Oil Extracts / Infusions
Excerpt from Practical Herbalism
Oil extracts are used mainly for topical applications, and as the base for salves or ointments. Oil extracts can be taken internally, but they are readily absorbed through the skin, and can be as much as 70 times more effective at delivering oil-soluble phyto-chemicals into the bloodstream than when the same herbs are ingested. Most beneficial plant constituents, including alkaloids, are at least partially soluble in oil.
Oil extracts fall into two general categories, cold infusions and those prepared with heat. Generally speaking, dried herbs are most easily extracted in oil by cold infusion, while fresh herbs are most readily extracted with heat. Delicate herbs and flowers, and those with high concentrations of volatile oils, should always be prepared by cold infusion whether they are fresh or dried. Cold infusions may take two weeks or more to finish, while hot extracts can often be made in a matter of hours.
Most good quality, cold-pressed, vegetable oils – the only kind that should be used – are highly susceptible to oxidation. They will quickly turn rancid if storage conditions are less than ideal. Natural preservatives can be used to extend the shelf life of oil products, but they must also be protected from heat, light, and air if they are to maintain good quality. Refrigerating oil extracts, and gently warming them when needed, will dramatically increase their shelf life. Most cold-pressed, unrefined vegetable oils should NEVER be subjected to the high heat of cooking, even to make herbal extracts.
The two vegetable oils that are the most naturally resistant to oxidation are Extra Virgin Olive Oil and Grapeseed Oil. Extra Virgin Olive Oil holds up well under higher temperatures. It is the preferred oil for making hot extracts. Grapeseed Oil is very high in protective antioxidant compounds, and is an excellent choice for cold oil infusions.
- 1 cup of finely chopped fresh or ground dried herb (minced fresh Garlic is an excellent choice).
- 10-12 oz. cold-pressed Grapeseed Oil
- 1 Quart Mason jar with lid
1. Place the herb and oil in the jar and seal. The oil should cover the herb by at least an inch.
2. Set the jar in a warm place, preferably in direct sunlight.
3. Shake at least twice daily for two weeks.
4. Strain off the oil. Fill into dark glass bottles, and seal tightly.
5. Store in the refrigerator, or, if a natural preservative has been used, in a cook, dark cabinet.
Hot Oil Extract
- A large heat resistant saucepan. Use un-chipped enamel ware, Pyrex, or stainless steel with a laminated bottom.NEVER use aluminum.
- 3-4 cups of chopped fresh herb
- Extra Virgin Olive Oil
1. Leave the pan uncovered. On an electric range eye, or in the oven, very slowly raise the temperature of the oil until the mixture just starts to bubble. Back off the temperature slightly – no more than 200 degrees F in the oven – until the bubbling is very slow but steady.
2. Simmer slowly this way and stir frequently until the herb material is completely crisp. This may take anywhere from 4-5 hours to a full day or more, depending upon the quantity and moisture content of the herb.
3. Strain, bottle and store as for Cold Infusions.
Preserving Oil Extracts:
There are several natural preservatives that can help extend the life of oil extracts. They may be used separately or in combination.
- Vitamin E Oil – blends perfectly with other oils, and acts as an effective antioxidant. Use approximately 1/4 tsp per ounce of oil extract.
- Tincture of Benzoin – extract of a tree resin with preservative properties. Use 1-2 drops per ounce of oil extract.
- Essential Oils – have varying levels of anti-microbial activity, and will help extend shelf life as well as add fragrance and therapeutic value.
- Myrrh – this Biblical resin may be tinctured, or simply crushed to a powder and added to oils as they are bottled. Use 4-5 drops of tincture or 1/4 tsp. of powdered resin per ounce of oil.
- Sage and Rosemary – adding some of either or both of these herbs (preferably fresh) to your mixture when preparing oil extracts will lend their antioxidant properties to the finished product. Wait until hot oil extracts are nearly finished before adding the Sage or Rosemary, and cover the pan to retain their volatile oils.
- Grapefruit Seed Extract – a little difficult to find, but highly effective as a preservative. Varies in strength, so follow the manufacturer’s recommendations.
Excerpt from The How to Herb Book
Herbs extracted in oil. Pound dried or fresh herb. Add 1 pint olive oil to 2 oz. of herb and let it sit in a warm place for 4 days or put mixture in a double boiler and gently heat oil for 1 or 2 hours. Press oil from herb. Some vitamin E may be added to help preserve it. Store in bottle in refrigerator.
Excerpt from Herbal Antibiotics
Oil infusions are exceptionally useful for burns, sunburn, chapped and dry skin, skin infections, and ear drops and for use on wounds as salves. The medicinal properties of the plant are transferred to an oil base. For a salve, the oil is made thick and moderately hard by added beeswax.
Using Dried Herbs
To make an oil infusion of dried herbs, take the herbs you wish to use and grind them into as fine a powder as possible. Place the herbs in a glass baking dish and cover with oil. Olive oil is a good choice because it is the one oil that will not go rancid; it is strongly antimicrobial. Stir the herbs to make sure they are well saturated with oil, then add just enough oil to cover them by 1/2 to 1/4 inch (13 to 6 1/4 mm). You may leave them in the sun for 2 weeks or bake them in the oven on the lowest heat your oven allows for 8 hours or overnight. Some herbalists prefer to simmer the herbs and oil for as many as 10 days at 100 degrees F (38 degrees C) in a slow cooker. When the preparation is ready, strain the oil out of the herbs by pressing in a strong cloth with a tight weave.
Using Fresh Herbs
To make an oil infusion from fresh herbs, place the herbs in a Mason jar and cover them with just enough oil to leave no part of the plant exposed to air. Let sit in the sun for 2 weeks, or cook in a Crock-Pot for 5 days at low setting. Then press the herbs through a cloth. Let the decanted oil sit. After a day, the water naturally present in the herbs will settle to the bottom. Pour off the oil and discard the water. Some herbalists prefer to start the oil infusion by letting the herb sit in just a bit of alcohol that has been poured over the leaves for 24 hours. This breaks down the cell walls of the plant and helps begin the extraction process. After this, add the oil and proceed as above.