Vacuum Sealing, then Freezing Garlic?

[natasha1270]

Thanks for confirming because the longer it steeps, the better. I keep it in the fridge just in case but I wasn't sure of the overall shelf life. Its very common Filipino condiment to use the vinegar for dipping.

[natasha1270]

National center for home food preservation article on garlic.

Thanks for this link, nickrey! It specifically states that garlic in vinegar can keep in the refrigerator for up to 4 months provided there is no sign of mold or yeast growth.

[jayt90]

As I recall, The USDA canning site warns against freezing fresh tomatoes, because there is not enough acid to prevent botulism.

Surely garlic would need more acid before freezing. I wouldn't mess with this, until I learned more about it from the USDA or university canning sites.

I think you might have confused the directives for canning and freezing. Easily done. Home canning of tomatoes can be an issue if there is not enough acidity but as far as I know they can be frozen without risk of botulism.

www.ext.colostate.edu/pubs/.../09341.ht...

Freezing is a safe, easy alternative to home canning. Frozen tomatoes and tomato products do not need added acid.

Not confused. Many people freeze trays of sliced tomatoes or whole tomatoes and have lived to tell us it is OK. The expert university sites I have seen say it is dangerous.

At the very least it is controversial.

[Martin Fisher]

C'mon!

That's nonsense!!!

Do you have a reference?

[gfweb]

"Official" guidelines are often the product of committees and are a compromise (as opposed to something generally agreed-upon by the committee). One crackpot outlier in the group can have outsized, and perhaps incorrect, effect on the product. I have witnessed this sort of thing. That's why critical thought shouldn't be suspended simply because an official group has a position. Their position is often wrong, or ill-considered. I wouldn't ignore it, but I wouldn't say its the final word on a subject either.

So far we've heard that some authorities don't like freezing garlic in a vacuum, but there's no explanation from them as to how they know its a bad thing. Counter to this is the pretty well-documented fact that the botulism bacillus doesn't grow at below freezing temps.

[Martin Fisher]

And nonsense gets repeated over and over and over until it becomes "fact."

[gfweb]

And nonsense gets repeated over and over and over until it becomes "fact."

Like drinking six glasses of water a day etc.

[FauxPas]

Not confused. Many people freeze trays of sliced tomatoes or whole tomatoes and have lived to tell us it is OK. The expert university sites I have seen say it is dangerous.

At the very least it is controversial.

Here are some expert university sites that say it is fine:

https://food.unl.edu/preservation/freezing-tomatoes

http://extension.missouri.edu/p/gh1503

http://nchfp.uga.edu/how/freeze/tomato.html

http://web.extension.illinois.edu/state/newsdetail.cfm?NewsID=15026

http://anrcatalog.ucdavis.edu/pdf/8116.pdf

All these sites state that it is fine to freeze raw tomatoes. You should wash them first, as you should with any produce, and you can hull them. Then you can put them in the freezer for months. If you like, you can blanch them before freezing and remove the skins. However, it is acceptable to freeze them with the skin. When you wish to use them, simply rinse under fairly hot water and the skins will peel off easily. (This is what I do.)

The only time botulism is discussed is when tomatoes are canned - they must have acid added to them to make them safe for canning and long-term storage.

Edited February 19, 2014 by FauxPas (log)

[jayt90]

OK, I am now up to date with this. 10 years ago there were extensive warnings, although I never knew anyone who got sick.

If freezing tomatoes is OK, why would anyone go to the trouble of canning? Millions of families do this every autumn.

[Martin Fisher]

It's always been safe to freeze tomatoes.

[FauxPas]

OK, I am now up to date with this. 10 years ago there were extensive warnings, although I never knew anyone who got sick.

If freezing tomatoes is OK, why would anyone go to the trouble of canning? Millions of families do this every autumn.

Honestly, I don't remember ever seeing warnings about freezing tomatoes and I've been canning/freezing for at least 20 years (though I am certainly no expert!).

But of course I remember lots of warnings about having to acidify any low-acid food before canning.

If you freeze tomatoes, you still have to cook them if you want a sauce or salsa. If you can tomatoes, you can make the sauce or salsa in advance or have your tomatoes already cooked, salted, seasoned, etc. Also properly canned tomatoes do not have to take up room in your fridge/freezer.

[dcarch]

And if you sun dry tomatoes, you will have tomatoes in the danger zone for many hours, days.

dcarch

[kayb]

FWIW...I take the big bag of peeled garlic cloves (sue me, I'm lazy) and poach them in olive oil, put them in a plastic bucket in the fridge, dig out by the tablespoonful when needed. I have not yet gotten ill from this practice.

I don't care for the brassy, metallic taste of fresh garlic. Poached and confited avoids that.

[Lisa Shock]

Part of the issue here is that modern tomato varieties are less acidic than they used to be. There were some really drastic changes in tomato types in the 60s and 70s that improved storage but changed the flavor and pH. So, wisdom from one's childhood no longer applies.

[Martin Fisher]

And the pH concern applies to canning (as noted above) and not to freezing.

[pbear]

FWIW, Chris, there's no need to vacuum seal garlic. I've been freezing for years the same product you're buying. I just put it in a plastic tub with a screw top lid (the one it used to come in, before they switched to pouches). It sublimates a bit over time, i.e., loses moisture which collects as ice in the tub, but the garlic is fine. Having it loose brings the convenience of being able to remove as many or few cloves as needed. Aternatively, I suppose you could split the difference and vacuum pack in 1/2 lb clumps, moving each to a tub as opened. This would have the same convenience advantage, but reduce the sublimation.

I agree with others that vacuum sealing isn't hazardous if freezing.* I'm just saying it's not necessary. Or even advantagous.

* Indeed, my research has found that the risk of botulism in garlic is greatly exaggerated, but I don't have time at the moment to dig up the references.

[Lisa Shock]

One reason why I'd be nervous about freezing vacuum sealed garlic is the number of times we've had people start message threads here about how their electricity went out and the contents of their freezer got warm. Freezing doesn't kill botulism spores. It just slows their activity and they won't reproduce. But, bring them up to 50°F+ in their their favored anaerobic environment (vacuum sealed) with plenty of low-acid, low-salt food (mushy, formerly raw garlic) and you'll potentially have issues after about 2 hours. If you live alone, and remember to toss the package if it gets unfrozen, great. If you go on vacation and let a house-sitter live there for two weeks every year, or have a forgetful mother-in-law who leaves food out on the counter, it might become an issue.

You can freeze it with some air in the bag, you could make a chopped mixture and add some salt and acid and freeze in a container with some air in it (easier to scoop out), you could make a chopped mixture and freeze it in tiny ice cube trays then pop out into a zipper baggie or seal with some air, etc. Oxygen, acid, and salt are the main ways to prevent botulism growth.

[gfweb]

One reason why I'd be nervous about freezing vacuum sealed garlic is the number of times we've had people start message threads here about how their electricity went out and the contents of their freezer got warm. Freezing doesn't kill botulism spores. It just slows their activity and they won't reproduce. But, bring them up to 50°F+ in their their favored anaerobic environment (vacuum sealed) with plenty of low-acid, low-salt food (mushy, formerly raw garlic) and you'll potentially have issues after about 2 hours. If you live alone, and remember to toss the package if it gets unfrozen, great. If you go on vacation and let a house-sitter live there for two weeks every year, or have a forgetful mother-in-law who leaves food out on the counter, it might become an issue.

You can freeze it with some air in the bag, you could make a chopped mixture and add some salt and acid and freeze in a container with some air in it (easier to scoop out), you could make a chopped mixture and freeze it in tiny ice cube trays then pop out into a zipper baggie or seal with some air, etc. Oxygen, acid, and salt are the main ways to prevent botulism growth.

That's an issue with everything in the freezer, though.

[Martin Fisher]

One reason why I'd be nervous about freezing vacuum sealed garlic is the number of times we've had people start message threads here about how their electricity went out and the contents of their freezer got warm. Freezing doesn't kill botulism spores. It just slows their activity and they won't reproduce. But, bring them up to 50°F+ in their their favored anaerobic environment (vacuum sealed) with plenty of low-acid, low-salt food (mushy, formerly raw garlic) and you'll potentially have issues after about 2 hours. If you live alone, and remember to toss the package if it gets unfrozen, great. If you go on vacation and let a house-sitter live there for two weeks every year, or have a forgetful mother-in-law who leaves food out on the counter, it might become an issue.

You can freeze it with some air in the bag, you could make a chopped mixture and add some salt and acid and freeze in a container with some air in it (easier to scoop out), you could make a chopped mixture and freeze it in tiny ice cube trays then pop out into a zipper baggie or seal with some air, etc. Oxygen, acid, and salt are the main ways to prevent botulism growth.

That's an issue with everything in the freezer, though.

Yep!

[pbear]

* Indeed, my research has found that the risk of botulism in garlic is greatly exaggerated, but I don't have time at the moment to dig up the references.

I had in mind, in particular, Table 3 of the CDC's report on U.S. botulism cases from 1990 to 2000, which identifies just two cases involving garlic in oil, affecting a total of four people.(in a nation of 300 million). Moreover, a couple months ago, I went through the annual surveillance reports (this is one of the links nickrey posted yesterday) for every year from 2001 to 2011 (the latest available) and found no other cases linked to garlic.

[Anna N]

* Indeed, my research has found that the risk of botulism in garlic is greatly exaggerated, but I don't have time at the moment to dig up the references.

I had in mind, in particular, Table 3 of the CDC's report on U.S. botulism cases from 1990 to 2000, which identifies just two cases involving garlic in oil, affecting a total of four people.(in a nation of 300 million). Moreover, a couple months ago, I went through the annual surveillance reports (this is one of the links nickrey posted yesterday) for every year from 2001 to 2011 (the latest available) and found no other cases linked to garlic.

These stats are the ones I am familiar with. What astounds me is not that over a 10 year period 4 people were affected by garlic oil but that in a nation of 300 million plus, with hundreds of recipes for garlic oil in books and on the web, ONLY 4 cases were reported.

[pbear]

I'm not surprised. Garlic in oil has very low available water.

[Lisa Shock]

Well, reporting is very infrequent. Even the CDC admits their numbers are only estimates. It's thought that one in six Americans gets a foodborne illness every year. Yet, look back through these forums at how many people claim that they've never known anyone who has suffered a foodborne illness. (I myself had salmonella when I was eleven and e.coli when I was 28.) Most people don't go to a doctor for mild cases. Those with worse cases may go to a doctor, but might not be tested for the precise cause. Outbreaks, cases with more than one victim, and those with younger victims tend to get reported more frequently, but not consistently.

When an elderly person who is already ill with some other condition dies, often times no autopsy is performed and no screening for other illness, so, foodborne illness is vastly under reported in the elderly population. I volunteer with a non-profit that works with people in hospice, we almost never see someone autopsied. (food gets brought in from outside all the time)

I've heard anecdotal evidence from friends that they were made ill by food in a restaurant, but, they never bothered to report it to any officials. That said, I think people are far more likely to report bad food in a restaurant than they are to turn on their grandmother and report her for making them ill.

You can see improvement in the number of cases of most foodborne illness as education mandates became stricter for frontline foodservice employees. Most large outbreaks in the past 25 years have been related to large corporate raw food producers or packers, not individual restaurants like that Canadian one in the 80s that sickened 37 people.

[gfweb]

Thing about botulism is that it gets reported (if its diagnosed). Patient ends up in a hospital invariably and hospitals report.

Unlike the usual food poisoning...nausea, vomiting...must've been something i ate...better in a day or two (unless it isn't) and never gets seen by a doc.

[djyee100]

Yes, people end up at the hospital to be treated--or at the medical examiner's to be autopsied. The CDC cannot be 100% certain that all cases have been reported, and they acknowledge that. There are always limitations to this kind of numbers-gathering. That's how it is. However, I'm willing to give the CDC a high level of credibility for its botulism statistics . There are only three sources of botulism antitoxin in the U.S., which ensures unusually good recordkeeping for known cases. As for unknown cases--that's speculation.

From the CDC National Botulism Surveillance:

All data regarding antitoxin releases and laboratory confirmation of cases are recorded annually by CDC and published on this website. Because CDC, the Alaska Division of Public Health, and the California Department of Health Services (CDHS), are the only sources of botulism antitoxin administered in the United States, nearly all recognized cases of botulism are reported.
http://www.cdc.gov/nationalsurveillance/botulism_surveillance.html