It’s so much fun to infuse your own oils. It takes care and caution to make them safely, but with the proper precautions they’re fantastic flavor enhancers and make great gifts.

You can make all kinds of quick homemade salad dressings using different combinations of infused oil, vinegar or lemon/lime juice, chopped onion, and fresh herbs. Or—you can use infused oils in marinades for veggies, chicken, or fish. They’re also great to cook with or dip bread in.

Freeze infused oils in an ice cube tray after you strain it to preserve seasonal flavors that won’t be around forever, like spring (or green) onions. They’re at their peak season now, so grab a bunch or two, make and freeze an oil, and you’ll have that tasty spring onion flavor even when winter rolls around.

Safety pointers for eating and gifting

Like canning, infusing oil is a process that can encourage the growth of botulism bacteria, particularly when using fresh ingredients like those spring onions. If you decide to make your own oils, and especially to gift them, you must be aware of these risks and how to prevent them.

There are a few simple ways to ensure that your oils are safe to enjoy. Home infused oils should always be immediately refrigerated and used right away or within a week. If you’d like to give an infused oil as a gift, it’s best to do it DIY-style. Make a card that includes these instructions and offer it with a nice, small bottle of oil bundled up with a homemade packet of herbs or spices.

There are additional health concerns surrounding oil infused with garlic. For this reason, it’s best to buy garlic-infused oil rather than attempt it at home.

In my own experience, I’ve found that cleanliness is always a good way to approach making home concoctions. Make sure that your hands, ingredients, work surface, and tools are completely clean. Wash and dry the ingredients you’re infusing with completely, as water in the oil will encourage rancidity.

It’s also a good idea to make your oils in sterile jars. The easiest way to sterilize is to run your jars through the dishwasher. You can also hold them in boiling water or at 250˚F in the oven for 10 minutes.

Be warned: There are a bazillion Internet recipes and how-tos on infused oils that use other methods and do not follow these guidelines nor warn of the risks. I recommend modifying them for optimum safety.

Heat infusion and cold process

There are two approaches to infusing oil (with heat or without), but many variations on the details. A good ballpark ratio for ingredients to oil is 1:4 (so about 1/4 cup of flavoring agents to 1 cup of oil).

With heat:

The easiest heating method is to just cook your ingredients in sizzling oil for 5 minutes, then strain the oil into a jar. You can also warm the ingredients in oil on a hotplate or in a slow cooker for several hours before straining.

Here’s my favorite, which preserves more of the ingredients’ properties and flavor:

1. Wash and dry ingredients completely, then muddle or bruise them. Place them into a sterile jar.
2. Gently heat oil over low heat in a non-reactive saucepan just until warm, about 1 to 5 minutes, depending on your quantity of oil. Allow to cool slightly, then pour into the jar, making sure that everything is completely submerged.
3. Cover tightly and allow to steep in the fridge for a couple hours to a couple days before straining into a new, clean container. Longer steeping time yields stronger flavors.
4. For fresh material, it’s best to warm the ingredients with the oil for an additional 10 minutes. You should strain fresh material out after 1 day.

Without heat:

Cold-process oils are best used with dried ingredients. You can pour the oil straight over the herbs, but I prefer blending them together, which really releases the flavors.

1. Wash and dry ingredients completely and place in a blender with oil. Blend until ingredients are evenly broken up. Pour into a sterile jar.
2. Cover tightly and allow to steep in the refrigerator for a couple hours to a couple days before straining into a new, clean container.

One last note—there is a big difference between therapeutic-grade herbal oils made for their medicinal properties and culinary oils made for flavor. As always, our focus here is on the tasty stuff. Keep that in mind as you browse info and recipes.

Check back on Friday to learn more about the benefits of hot versus cold-process oils, and about the professionally-preferred cold-process method, called Agrumato.

Sources:
Colorado State University Extension. (2011, August 29). Oil infusions and the risk of botulism. Retrieved from http://www.ext.colostate.edu/safefood/newsltr/v2n4s08.html

Chang, A., Goodrich, R., & Schneider, K. (2011, October). Preventing foodborne illness: Clostridium botulinum. Retrieved from http://edis.ifas.ufl.edu/fs104