Making Herb-Infused Oils
Herb oils are made by blanching fresh herbs to lock in their bright green pigment and then blending them with a neutral oil before straining. This process captures the raw scent and color of the garden without the risk of fermentation that occurs when raw herbs sit in oil for too long.
Temperature control preserves the color.
If you skip the ice bath, your oil will turn a muddy, brownish-green within hours. Keep your equipment dry; water is the enemy of shelf-stable oils.
- Small saucepan
- Fine-mesh strainer
- High-speed blender
- Cheesecloth or coffee filter
- Ice bowl
What goes in.
- 2 cupsfresh herbs, tightly packed (basil, parsley, or chives work best)
- 1 cupneutral oil (grapeseed or sunflower)
- to tastesalt
Shocking the chlorophyll
Submerging herbs in boiling water for exactly ten seconds sets the enzymes. Following immediately with an ice bath freezes that vivid color in place.
The method.
Prepare your setup
Fill a bowl with ice and water. Set a strainer nearby.
Blanch the herbs
Drop the herbs into a pot of boiling water for 10 seconds. Use a spider or tongs to fish them out immediately and plunge them into the ice water.
Dry completely
Squeeze the cold herbs between clean kitchen towels. You want them as dry as possible to ensure a clean emulsification.
Blend
Add herbs and oil to the blender. Run on high until the oil turns deep green and looks uniform. The blender friction will warm the oil slightly, which helps with color extraction.
Strain
Line your strainer with cheesecloth or a coffee filter. Pour the oil through and let it drip naturally. Do not press the solids, or the oil will look cloudy.
When it doesn't go to plan.
Store in a dark glass bottle to prevent light from degrading the color.
Use this oil within three to five days if kept refrigerated.
If you want a stronger aroma, add a small clove of garlic to the blender, but note that this reduces the shelf life significantly.
The ones that keep coming up.
Why can't I just put herbs in a bottle of oil?
Raw herbs contain water, which creates a breeding ground for bacteria when sealed in an oxygen-free oil environment. Blanching and straining removes this moisture.
Can I use olive oil?
You can, but its strong natural flavor will often overpower delicate herbs like basil or parsley. A neutral oil lets the herb character lead.