Pressure canning basil pesto
Herbs and oils are both low-acid and together could support the growth of the disease-causing Clostridium botulinum bacteria. Oils may be flavored with herbs if they are made up for fresh use, stored in the refrigerator and used within 2 to 3 days. There are no canning recommendations. Fresh herbs must be washed well and dried completely before storing in the oil. The very best sanitation and personal hygiene practices must be used. Pesto is an uncooked seasoning mixture of herbs, usually including fresh basil, and some oil. It may be frozen for long term storage; there are no home canning recommendations. This is from the National Center for Home Food Preservation at the University of Georgia. They do all the research for USDA. I think the very high temperature (240 degrees) would make the pesto mush and very unpalatable. companies that sell it in jars, shelf stable, have had to meet a lot of testing standards.both for safety and quality. They have different equipment than what is available for us to use at home. Freeze or eat it fresh, no canning. Thank you for your question. In Iowa a great resource for canning questions is Answerline 1-800-262-3804, talk to a live person during the week. Good luck!