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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!?

                  1. Wondering if anyone wants to jump back on this thread...

                    I love roasted garlic but don't use it much because it takes a full hour and doesn't fit into my food prep routines very well. However, I recently caught wind of someone saying that they roast a bunch of garlic at once and then mash and freeze the roasted cloves...no oil.

                    Is frozen, cooked garlic w/o oil safe? For that matter, is frozen, raw garlic w/o oil safe? I'll call my ag school extension agent on Monday, but thought I'd see what people here know in the mean time.

                    Thanks in advance!

                    9 Replies
                      1. re: smilingal

                        I haven't found the answer to my specific question about roasted garlic yet. Supposedly a food preservation expert will be getting back to me. But I did find some useful tidbits:

                        This USDA fact sheet on botulism suggests that botulism spores are killed at 240-250F, so roasting garlic would seem to solve that problem altogether: http://www.fsis.usda.gov/Factsheets/C....

                        Also, the National Center for Home Food Preservation says that raw garlic in oil can be frozen for several months: http://nchfp.uga.edu/how/freeze/garli....

                        I'll update this thread if I hear from the extension agent.

                        1. re: smilingal

                          Smilingal, I have some more info for you.

                          The extension agent got back to me, and said it would be fine to freeze roasted garlic, though she recommended using mason jars rather than plastic bags for the odor factor. (I actually find that roasted garlic doesn't have much of an odor, but maybe that's just me.)

                          She also pointed me to the following document from North Dakota State University: http://www.ag.ndsu.edu/pubs/plantsci/.... It has tons of info on garlic, including preservation. Here's a tidbit I found particularly relevant to this discussion: Never store garlic in oil at room temp. Keep in fridge for up to ONE week, or freeze. (No date for frozen garlic-in-oil given.


                          Anyway, that's that. Thanks for the input everyone! I froze my first round of roasted garlic last week and it worked great.

                        2. re: APK_101

                          While it does take an hour or longer, it requires almost no prep work and absolutely no monitoring. It's the kind of thing to throw in the oven while you watch the game or a movie. You could certainly store it in oil for a couple of weeks without any health concerns---although frankly if I was going to go through the trouble of peeling the cloves and using oil I'd make mojo de ajo and be done with it.

                          I simply let the roasted head cool on the counter for a bit and then toss it in the fridge, pulling off cloves as I need them. Anything I don't use up in a week or so gets tossed in the freezer or just tossed, and I start over again.

                          1. re: eight_inch_pestle

                            I freaking hate peeling garlic. My thought is that I will buy the big 3 lb tub of peeled garlic cloves at Costco at roast most of it all at once, then freeze the roasted cloves for later. BTW, I had never heard of mojo de ajo so I googled it, and it looks incredible!

                            1. re: APK_101

                              It is tasty stuff, that mojo de ajo. Amazing for sautéing shrimp with a little cilantro and chile.

                              Your plan sounds solid. JFYI, once you roast the whole head you can squeeze the soft pulp out of the peel---no peeling required. In any event, good luck!

                          2. re: APK_101

                            What I do is make garlic confit once in a while - I buy one of those 3lb containers of pre-peeled garlic, and dump the whole thing in a pot with olive oil to cover. bring it to a low simmer and let it go until the cloves are soft and golden brown. Strain off most of the oil and freeze the garlic - I just throw it in ziploc bags and flatten them. The residual oil keeps it soft enough that you can easily break off pieces without thawing the whole thing, and to my knowledge it's as safe to freeze as anything else. The strained oil I keep in the fridge for cooking and salad dressings. A 3lb container of garlic makes enough to keep me in confit for about a year, probably! BTW - I used to keep it in the fridge for months on end (and never died), but I started freezing it once Chowhound put the fear of botulism into me.

                            1. re: biondanonima

                              Yes! This is what I want to do. Thanks for the info. I will try this straightaway. (Or as soon as I can bring myself to go to Costco. :))

                              1. re: APK_101

                                Why does it only take me 35 minutes at most to roast Garlic when everyone else says it takes an hour?

                                This is @ 350F.

                          3. You can squish onto cling wrap and twist into a tight ball for freezing.

                            Regarding jarred garlic, commerically, the manufacturer adds an acid to the garlic (citric acid?). Also, I believe there is a pressure canning step in the process. The acid and the pressure canning will neutralize bot. spores.

                            1. Just an FYI, I roast a whole head or two of garlic at once. I do not do the individual peeled cloves, as I agree, it's a lot of work to peel them all. Just remove the loose layers of paper, then slice the top off, about a quarter of the way down, trying to expose the tops of most cloves. Put in a a square of heavy duty foil, and drizzle with olive oil, and a pinch of salt. Seal up and roast until the package is soft when squeezed. At 350 it takes about 1/2 hour. Lower temps will be about 45 mins to an hour. I sometimes throw them in while using the oven for something else. When done & cooled, I squeeze out the pulp at once. From here, you can cover with oil, and refrigerate for about two weeks, or I like to mix them with some mayo & lemon juice and use as a sandwich spread.

                              1. The University of California published an article on properly storing garlic. The article was written in 1997 and stated that three cases (I assume deadly) of Clostridium Botulinum were reported in North America. The article recommends that garlic stored in oils can be kept for several months in the freezer. Please take a moment to read the article anrcatalog.ucdavis.edu/pdf/7231.pdf‎.