Yes, you can put fresh herbs in olive oil, but it's crucial to do so safely to prevent botulism.
Safety Considerations for Infusing Olive Oil with Fresh Herbs
The primary risk when infusing olive oil with fresh herbs is the potential for botulism. Botulism is a severe illness caused by a toxin produced by the bacterium Clostridium botulinum. This bacterium thrives in low-oxygen environments, like olive oil, and can grow if fresh herbs harbor spores.
Safe Methods for Infusing Olive Oil with Fresh Herbs
To safely infuse olive oil with fresh herbs, follow these precautions:
- Use Fresh, Clean Herbs: Thoroughly wash and dry the herbs. Wilting or damaged herbs are more likely to harbor bacteria.
- Properly Prepare the Herbs: Consider lightly blanching the herbs in boiling water for a few seconds to kill surface bacteria. Then, thoroughly dry them.
- Refrigerate Immediately: Store the infused oil in the refrigerator at 40°F (4°C) or lower. This slows down the growth of Clostridium botulinum.
- Use Quickly: Use the infused oil within 2-3 days. The longer it sits, the greater the risk of botulism.
- Freezing: Freezing the infused oil is another option for longer-term storage.
Steps to Infuse Olive Oil (with Safety in Mind)
- Sterilize Your Bottle: Use a clean and sterilized airtight bottle or jar.
- Prepare the Herbs: Wash and thoroughly dry your selected fresh herbs (basil, thyme, rosemary, oregano are good choices). You may optionally blanch them briefly.
- Combine Herbs and Oil: Place the herbs in the sterilized bottle.
- Pour in Olive Oil: Use a funnel to carefully pour high-quality olive oil over the herbs, ensuring they are completely submerged.
- Seal and Refrigerate: Seal the bottle tightly and immediately refrigerate.
- Use within 2-3 days or freeze.
Why Refrigeration is Important
Refrigeration significantly slows down the growth of Clostridium botulinum, reducing the risk of botulism.
Alternative: Dried Herbs
A safer alternative is to use dried herbs. Dried herbs contain much less moisture, making it less likely for Clostridium botulinum to grow. You can infuse olive oil with dried herbs at room temperature, although refrigeration is still recommended for long-term storage (beyond a couple of weeks) and to prevent the oil from going rancid.
