Current Food Safety Issues of Home-prepared Vegetables and Herbs Stored in Oil

Consumer interest in storing vegetables or herbs in oil or infusing oils with these products has grown over recent decades. Vegetables and herbs stored in oil provide several conditions necessary for botulinum toxin production, including an anaerobic environment.Studies of documented outbreaks of botulism have identified vegetables and herbs in oil as the food source, with most outbreaks traced to home-prepared versions. Implicated foods include peppers, garlic, mushrooms, and eggplant. Visual or other organoleptic clues do not provide adequate information to prevent botulism. Most Cooperative Extension resources have communicated the risks and hazards of storing these foods at room temperature and suggest refrigeration, freezing, drying, and acidifying as alternatives.The safest recommendation is to freeze vegetables or herbs stored in oil. If the product is not frozen, it should be refrigerated and then either consumed within four days or discarded. Future research is required to clarify the potential of additional hurdles to preparing and storing these foods safely. Possible research areas include the use of boiling water canning, acidification, and drying followed by an acid dip.