Mountain Rose Herbs Blog

How to Make Herb-Infused Oils for Culinary & Body Care Use

Written by Irene | August 13, 2019

The world of herbalism is intriguing, vast . . . and sometimes intimidating! Projects like creating tinctures using the percolation method, or making your own mead, can seem daunting for those new to the botanical arts. That's why when we're trying to help a friend get started in herbs without overwhelming them, we often recommend one of our favorite herbalism projects for beginners: making herb-infused oils.

Simply infusing a carrier oil with herbs will transform it into a versatile ingredient. There are several ways to infuse oils, but our favorite is the "folk" or "simplers" method, which relies on the sun to naturally infuse oil with herbal properties. We have also a quick method if you're short on time, as well as an alcohol intermediary method for creating very shelf-stable oil infusions perfect for salves and other body care formulations!  

Many different organic carrier oils may be used, however fractionated (MCT) coconut oil and olive oil are popular and wise choices because they have long shelf lives and are suitable for many applications. Herbal oils can be used to create marinades, massage oils, salves, lip balms, facial serumshair treatments, body creams, soaps, and more!

Oil Infusing Basics:

  • While most herbs can be infused either dried or fresh (with proper preparation), some lend themselves better to one form than the other. A famous example is St. John's wort, which is widely believed to require fresh material to create an effective herbal oil.
  • Herbal oils can turn rancid or grow mold, especially if the carrier oil used is not very shelf stable (such as rosehip seed oil) or if fresh herbs are used. Infused oils that exhibit any change in color, scent, clarity, or taste should be discarded for safety. Using the alcohol intermediary infusion method or adding a preservative like vitamin E can help keep oils stable longer, but it will also make them unsuitable for eating.
  • Herbs with natural dyes may be infused in oil for use in adding color to soaps and other body care formulations.
  • You may want to wear gloves when it comes time to strain a finished herbal oil through a cheesecloth-lined strainer and to squeeze out any oil remaining in the herbs. While you can use your bare hands, working with oils is a messy process, and certain herbs, like turmeric, may temporarily stain your hands and jewelry.
  • Often, the oil will not wash out of cheesecloth or muslin, so make sure you strain with something you’re not going to reuse.
  • Even after straining, fine herb sediment can make oil a bit gritty—if this bothers you, strain again through a coffee filter. This is a slow-drip process and may require more than one coffee filter to strain all the oil.
  • You can blend herbs together for synergistic infusions. For example, hops flowers, lavender flowers, and chamomile flowers infused together in jojoba oil make a wonderful relaxing blend for use with massage. Mix and match to suit your needs!

How to Infuse Oil with Herbs (3 Methods)

Folk (Simplers) Method for Solar-Infused Oils

Use the sun to naturally infuse oil with the goodness of your organic herbs! Herbal oils made using this method can be used for both culinary and body care recipes. For example, rosemary-infused olive oil makes for an excellent hydrating hair mask—or a flavorful salad dressing base! For food purposes, just be sure that the oil and the herb(s) you choose are both tasty and safe to eat.

Directions

  1. Place herbs in a clean, dry quart jar. Leave at least 1 to 3 inches of open space above your herbs to cover with oil.
  2. Fill remaining space in jar with oil of choice, making sure to cover herbs by at least 1 inch or more. If the herbs emerge above the surface of the oil at any point while infusing, pour more oil on top to ensure the herbs remain covered.
  3. Cap the jar tightly and shake well.
  4. Place jar in a sunny, warm windowsill and shake once or more per day.
  5. After 2 to 3 weeks, strain the herbs out of the oil using cheesecloth or a mesh strainer. Make sure to squeeze out as much of the precious oil as possible!
  6. Pour into clean glass bottles.
  7. Label your jars with the date, type of oil, and herbs used.
  8. Store in a cool, dark place. The oil may keep for up to a year. Vitamin E oil at a concentration of up to 1% may also be added to prolong shelf life for oils to be used topically.

Pro Tips

  • While infusing with the slow folk method, you can cover the jar with a brown paper bag if you prefer to keep it away from direct sunlight. According to Rosemary Gladstar, using the sun to infuse herbs in oil is a very old folk practice that has worked for our ancestors for centuries!
  • The amount of herbs used will depend on the size of the jar, as you want to leave at least a couple inches of space for oil coverage or any swelling that may occur as the herbs soak up oil.
  • It is fairly common to have some pieces of your herbs that will float in the oil after saturation. If these float to the top and start to mold or decay, simply skim them off and discard.

Quick Method for Heat-Infused Oils

The quick method utilizing heat is sometimes necessary when herbal oils need to be created in a pinch. Much care needs to be taken when crafting herbal oils this way because you don't want to deep-fry your herbs! As with the folk method above, heat-infused oils can be used in both culinary and apothecary preparations, as long as both the oil and the herb(s) you choose are suitable to ingest.

Directions

  1. Place herbs in crock-pot, double boiler, or electric yogurt maker, and cover with organic extra virgin olive oil (or other carrier oil of choice), leaving at least an inch or two of oil above the herbs. 
  2. Gently heat the herbs over very low heat (preferably between 100° and 140° F for 1 to 5 hours, until the oil takes on the color and scent of the herb. Some texts recommend heating the oil 48 to 72 hours at a controlled temperature of 100° F. Turn off heat and allow to cool.
  3. Once oil is cooled, strain using cheesecloth.
  4. Bottle in dry, sterilized glass bottles. Be sure to label your bottles with the date and contents before storing them.
  5. Store in a cool, dark, dry place for up to six months. Vitamin E oil at a concentration of up to 1% may also be added to prolong shelf life for oils to be used topically.

Pro Tips:

  • As with the folk method, the amount of herbs used will depend on the size of the jar, as you want to leave at least a couple inches of space for oil coverage or any swelling that may occur as the herbs soak up oil.

Alcohol Intermediary Method for TOPICAL Herbal Oils

The alcohol intermediary method requires 24 hours to complete and should only be used for dried herbs, but it makes for herbal oils that are much less prone to contamination than those infused using the other two methods described above. Plus, the chemical and physical release processes facilitated by the alcohol and the grinding help to extract the maximum amount of goodness from your botanicals, yielding oils of exceptional color and potency.

Note that these oils are NOT suitable for eating—even though most of the alcohol will evaporate off during the process, a detectable and unpleasant taste will remain.

Watch clinical herbalist Maria Noël Groves of Wintergreen Botanicals demonstrate how to make plantain-infused olive oil using the alcohol intermediary method!

Directions

  1. Weigh out approximately 1 oz. dried organic herb(s).
  2. Using a blender, coffee grinder, or bullet grinder, grind into coarse powder (don’t grind too fine, or it will be difficult to strain later). 
  3. Transfer ground herbs into clean jar with tight fitting lid.
  4. Measure out 1/2 oz. whole grain alcohol (like Everclear) or vodka.
  5. Pour alcohol into jar with ground herbs.
  6. Use a fork to work together, or put lid on and shake to disperse the alcohol through herb material—it should be the consistency of nice soil or damp beach sand.
  7. Set aside for at least 24 hours to allow the herbs to macerate in alcohol.
  8. Put damp herb material into a standing blender.
  9. Add approximately 8 oz. of carrier oil, measured by volume or weight. Add more as necessary to cover well and ensure herbs are moving around in blender.
  10. Blend until blender jar is warm to the touch, about 5 minutes.
  11. Place a good-sized mesh strainer over heat-safe glass bowl. Line strainer with cheesecloth or fine muslin.
  12. Pour herb-infused oil through lined strainer and use the cheesecloth or muslin to squeeze out as much of the oil as possible from herbs.
  13. Oil should keep a year or more when stored in cool, dark, dry place.

Pro Tips

  • A measuring shot glass works great for getting accurate measurements of small quantities of alcohol.
  • If you don’t need to use your standing blender for other things in the next 24 hours, and if it has an airtight lid, you can skip the step of putting the ground herbs and alcohol into a separate jar. Instead, grind the herbs in the blender, then add the alcohol to the blender container, mix as directed above, put the lid on tightly, and let sit for 24 hours right in the container.
  • Some “fluffy” herbs like calendula won’t grind well in one fell swoop, so grind these in smaller quantities to get a good consistency.

Herbs to Infuse in Oil

There are a countless number of herbs (and even resins!) that can be infused into oil, depending on your needs. We always suggest using organic herbs whenever possible to ensure you are not adding synthetic chemicals to your creations. We also generally recommend using dried herbs. If you want to use fresh herbs, wilt them first for 12 hours to remove the moisture (too much water will cause your oil to go rancid), cut into small pieces, and crush with a mortar and pestle before adding to your infusion container.

Here are some of the most commonly used herbs:

 

Want to create Skin care products with your infused oil?

Learn How to Create a Salve with Herbal Oil!

 

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