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Mar 29, 2011 02:04 PM

how to keep roasted garlic

I'm not sure what I was thinking, but a couple days ago I roasted a head of garlic & only used a little.. Now I'm going out of town for a week,, is there a way to keep it? I thought about trying to freeze it but now I'm thinking maybe squished out of the wrapper and in the fridge covered with olive oil. Any suggestions?

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  1. Freezing is fine. Raw garlic in olive oil poses a botulism hazard - not sure about cooked.

    1 Reply
    1. re: greygarious

      As long as the roasted garlic is completely covered with oil it should be fine for a week .Keep it in the coldest part of your fridge.Freezing is also a viable option.

    2. Thanks, I think I will freeze it. Texture shouldn't be an issue and also I won't have to use it right away when I get back.

        1. Clostridium Botulinum requires very, very high heat to kill the spores, much higher than you got roasting your garlic. Storing it in oil in the fridge creates the perfect anaerobic environment for those spores to produce a very nasty neurotoxin that you can neither smell nor taste and results fairly quickly in paralysis and death. Raw or cooked cloves in garlic oil are good for 2 weeks, 3 weeks max. Store it in the freezer (that slows the spores down a little) and then use it up quickly when you get back.

          10 Replies
          1. re: morwen

            Instead of high heat would the length of time for heating help with destroying the spores? I sometimes simmer garlic in oil for about an hour (garlic confit) & I was wondering if that length of time (at a somewhat low heat) kills anything. And freezing only slows spores down a LITTLE? Seriously? What about freezing peeled garlic cloves not in oil? Like the big jar of peeled cloves from Costco.

            1. re: sparkareno

              Botulinum spores are all around us and on practically everything including produce you pull from your own garden. In the normal course of things it passes harmlessly through the body because conditions are not right to trigger the spores into producing toxin. However, put them in an environment with low acidity and no air and those little buggers will go to town. Home pressure canning raises the heat needed to inactivate (but not destroy) the spores in most low acid foods where water bathing won't, but those products usually contain only small amounts of oil or grease. It's recommended that anything home pressure canned be boiled 20 minutes before consuming. Unfortunately, garlic and fresh herb oils are not candidates for home pressure canning, and given their composition, home pressure canning won't do the job.

              Usually, if you look on the label, you'll see that commercially processed jars of garlic cloves in water have an acidifying agent of some sort added. Freezing is fine. It won't get rid of the spores, only inactivate them, and water doesn't exclude oxygen like oil does.

              Commercially processed jars of garlic in oil undergo canning processes and temperatures that aren't available to the home cook. That also applies to those other veg products stored in oil- peppers, dipping oils using fresh herbs, etc. But honestly, I personally either keep them in the freezer or toss them 3 weeks after I've cracked them open just to be safe. Here's a note though: if you create dipping (or other) oil using dried herbs they are much safer.

              You can make these fresh garlic/herb products at home and use them safely. Just make them in small amounts and use them quickly. Always label and date them with either a day made or use by date so you know when to toss them.

              At a master preserver conference I attended recently we were discussing botulinum poisoning and the problems we have convincing canning students of the dangers. One of the doctorates attending told us a recent instance of a physician and his wife here in VA , who both passed away after consuming home made garlic cloves in oil that had been kept too long. It was a graphic and disturbing recounting and certainly convinced me to hammer this home to my students. Remember, the toxin is odorless and tasteless, you can't detect it without lab equipment. Tossing a jar that's questionable is the cheap, easy way to stay safe.

              1. re: morwen

                geeze - thanks - i have a whole new outlook! Thank you. Since you seem to be one in the know - I was wondering, as I refrigerated the leftover FF evaporated milk, how long can that stay?

                1. re: smilingal

                  I can't remember the last time I used evaporated milk! Ask the candy makers and the bakers. Home food preservation is more my thing. Sorry. ;-)

                2. re: morwen

                  I am scared to think of what toxins were consumed by many rich people from eating the food at a catering company I used to work at, we would regularly puree large amounts of raw garlic and keep it for long periods of time. In hindsight that was probably only one of many potentially deadly practices that this so-called high-end catering company engaged in.

                  1. re: dowlf

                    Definitely! It's been awhile since I was working in restaurant kitchens and there's a whole lot of "If I knew then what I know now" things that I wouldn't have done. That was before the days of Safe-Serve certification and actually just on the cusp of advances in home canning food science regarding things like the ph and temp requirements, actual acidity of tomatoes, bacterias, molds, etc and their effects on home canned food. I hear a lot of "but mom and/or granma did it this way and we're still alive" and I have to point out that mom/granma and food science didn't know then what we know now, and that "touch of stomach flu" may actually have been mild food poisoning. I also look with an extremely critical eye at the glut of home preserving books coming on the market because canning is "hot" right now. It's not unusual for me to find recipes I would deem suspicious from time to time. And there's any number of online recipes that have a high potential for making you sick.

                    Local county cooperative extension offices offer free beginning home canning classes on a regular basis (and safe-serve certification for a small fee) and I recommend them whether you're into preserving or not because you will learn a lot about preventing and avoiding food-borne illnesses.

                    1. re: morwen

                      I know you mentioned the mom and grama thing. But my family has been preserving garlic for over 10 years. As in they have jars of garlic preserved for over 10 years. By your previous explanation, we should have all been paralyzed with one taste. Maybe you can clarify if they've been preserving in some sort of magical way that's not indicated in your last post. Just a side note that my uncle has a jar of garlic about 30 years old.

                  2. re: morwen

                    Thanks for giving such a great and complete explanation.

                3. re: morwen

                  Agree. Only cover in olive oil completely if you are going to use the garlic/oil within about a week otherwise don't risk getting sick.........like deathly sick. Frankly if you were dealing with a lot of roasted garlics then I'd freeze them but for just one bulb I'd use it in a sandwich somehow and eat it now.

                  1. re: Puffin3

                    I believe all the ag. extension pieces (and maybe a CDC piece) I've seen have said two weeks, not one week.

                4. really - I am aghast! I often will saute thinly sliced or minced garlic in oil and then store in a jar in the fridge and use that to saute other foods --- and am embarrassed to say how long I have kept it. Also, spark brought up a good point --- what about either Costco's or even the supermarket jars of garlic - in a jar - with or without oils. Those don't get used up in 2-3 weeks!?