It's Your Health
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Garlic-in-oil is a popular homemade food item that can cause serious health problems if it is not stored properly. If you make and use this item at home, you can take steps to protect your family from the possibility of food poisoning.
Garlic-in-oil is a mixture of oil and garlic, either whole, chopped or minced. When you make it at home and use it right away, it is a safe product. It is also safe if you keep it refrigerated on a continuous basis, and use it within a week.
The trouble starts if you store homemade garlic-in-oil at room temperature, or if you keep it in the fridge for too long. These actions could allow growth of the spores that cause botulism, resulting in the production of toxin in the food.
The bacteria spores that cause botulism – Clostridium botulinum – are widespread in nature, but they seldom cause problems, because they are not able to grow if they are exposed to oxygen. If the spores do not grow, then they cannot produce the toxins that cause illness.
However, when garlic containing the bacteria is covered with oil, there is no oxygen present. This means that conditions are ripe for the spores to grow and produce toxins. You can slow down the growth of bacteria (and the production of toxins) by refrigerating the product, but this may not be enough to stop it from spoiling.
What is worse is that there will not be any obvious signs that the garlic-in-oil is spoiled. You will not be able to tell if it is dangerous, because it will still look, smell, and taste the same.
If you eat garlic-in-oil that contains the toxins, you can get botulism, a potentially fatal food poisoning that could cause the following symptoms:
Commercially produced garlic-in-oil products have been linked to two outbreaks of botulism: one in Vancouver in 1985, and the other in New York in 1989.
In both outbreaks, people became seriously ill after eating something made with non-preserved garlic-in-oil that had not been stored at the proper temperature. Since then, the commercial manufacturers of garlic-in-oil have adopted better preservation techniques to keep their products free of the toxins that cause botulism.
Check the label on commercially prepared garlic-in-oil products for sale. If salt or acids are in the list of ingredients, then the product has been preserved and you do not need to worry about food poisoning, as long as you follow directions for storing the product.
You can protect your family's health and reduce the chance of food poisoning by following these rules:
Health Canada continues to work closely with the food industry to ensure that commercially prepared garlic-in-oil products are safe. In addition, Health Canada is helping to get the word out to consumers about ways to make sure that home-made garlic-in-oil products are also safe.
Botulism Reference Service
Health Canada, Research Division
251 Sir Frederick Banting Driveway, Tunney's Pasture
Ottawa, ON K1A 0K9
Also, see the following Health Canada Web sections:
It's Your Health articles on Food and Nutrition
And, see the Canadian Food Inspection Agency's Pathogen: Clostridium botulinum - bacteria or you can call 1-800-442-2342
For more information on Food Safety and food borne illnesses go to the following Web sites:
For additional articles on health and safety issues, go to the It's Your Health Web section You can also call toll free at 1-866-225-0709 or TTY at 1-800-276-1245*.
Updated: February 2009
Original: November 2001
©Her Majesty the Queen in Right of Canada, represented by the Minister of Health, 2009