Sunday, January 31, 2010

carrots in the jar with acid



first you need to click on this link get the melody in your head and continue:

picture yourself in a jar underwater
with salt, herbs and spices, and vinegar too
suddenly bubbles appear at the surface
what's a few b-cells to do?

flat lids and screw caps and boiling water
towering over your head
look for the cell with the b in it's name
and it's gone

(ta, ta, ta)

carrots in the jar with acid
carrots in the jar with acid
carrots in the jar with acid

....ahem.

if you're one of the can jammers, or if you're following along at home then you know that the noble carrot is the vegetable in focus this month. (even if you don't give a damn about canning in february but will be hot water bath canning veggies sometime later in the year, then read on - it's important!)

...because we're gonna talk about the b word.



yes i am talking about botulism, please read about it here, here and read this one too.

after you're done reading, the next logical question would be: what can i do to insure that the carrots (or any other vegetable for that matter) i hot water bath process do not kill me or my loved ones?

there's exactly two things that will prevent this from happening:

1) the jars are boiled for long enough to kill off the clostridium botulinum vegetative cells.
2) the food in the jars is acidic enough to prevent the clostridium botulinum spores from germinating into cells.

clostridium botulinum bacteria has two forms; vegetative cells - these produce the killer toxin, and protective structures called spores. when we boil the jars for the properly allotted time we kill the cells, but the spores survive. in a favorable environment the spores will germinate into the vegetative cells that produce the deadly botulinum toxin.

here, let me break it down for ya: clostridium botulinum is a common microorganism found in soil all over the world. there's no problem with it when it is exposed to oxygen, but when conditions are favorable for it to thrive it can become deadly. what are the conditions?

no air and low acidity.

since we are forcing the air out of the jars when we hot water bath can, i.e creating a very favorable environment for germination, it is imperative that the acid level is high enough to prevent this from happening.

got it?

so when hot water bath canning low-acid foods (veggies not fruit) you will most likely be making pickles or chutneys and this is my advice to you:

1) use a reputable source written or updated 1995 or later - or check with the usda.
2) never vary the amount of vinegar, water or vegetables in the recipe. (herbs, spices, salt & sugar are ok)



3) use vinegar that is 5% acidity or higher (it's marked on the label) - homemade vinegars are not ok because acidity level is unknown.
4) never boil the vinegar mixture longer than the recipe states.

if you are a newbie pickler i would also caution against switching out types of vegetables in the recipe, because boiling time differs for different veggies. in mixed pickles boiling time is always set for the vegetable that requires the longest amount of boiling time.

i would also not be in a rush to purchase a pH meter. a pH level of 4.6 or lower is required to prevent the germination of spores, and pickling recipes from reputable sources fall way within the realm of safety, usually within the 2.6 - 4.0 range. so if you follow the recipe exactly as outlined above ya got nothin' to worry about. (plus you'll either have to wait for 3 weeks after the pickles are canned or puree one whole jar of food before it's canned to test accurately)


i say your $ is better spent on a good source of recipes and these are some of my picks:



so easy to preserve by elizabeth andress and judy harrison
from the U of GA's cooperative extension, should be on every home preserver's bookshelf








the joy of pickling by linda ziedrich
the indisputable pickler's bible






well preserved by eugenia bone
not a ton of canning recipes, but what's here is a cut above








well preserved by mary anne dragan
a lot of inventive recipes suitable for water bath canning






the new preserves by anne v. nelson
a little book with big recipes






ball complete book of home preserving by judi kingry & lauren devine
another bible sure to follow current usda standards





the national center for home food preservation has a website with a wealth of information that every home canner should be familiar with. there you can find the entire usda complete guide to home canning, 2009 revision available for download, free!

...any questions?

20 comments:

  1. fantastic coverage on a very vital topic! i wish my book was out now. it covers this in extensive detail. kudos to you for clarifying it all so well!
    totally digging the beatles groove. "carrots in the jaaarrrr with aaacidddd..."

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  2. Somehow when the word acid comes up for the Beatles I don't think they think of the acid in canning jars! what a great article and clever song.

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  3. ashley - thanks so much! i've long felt that there's a lot of misunderstanding surrounding the b word and home canning and i've tried to be as concise and factual as could be...and so glad you're digging the beatles groove! you must play it when you're canning your feb can jam 'entry'!

    frugal canner - you have no idea how much i enjoy it when i have proof that someone actually gets my double entendres ('cause i never know if they work or not! :)

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  4. I have to chime in and update your 2) and say never change the amount of vinegar, food OR WATER in a picking recipe. Hope this helps! I am totally looking forward to this month's challenge!

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  5. mother's kitchen - yes you are so right, i am adding that up there right now!

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  6. Brava! This needed to be rounded up in a clear fashion, and you did just that. And with your trademark style--pairing up utter no nonsense biznez with your great sense of humor. Tha's riiight.

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  7. Nice! While I kinda don't like to follow a recipe, I kinda love living. I need to know what I can and can't do. Thx Much, T!

    I'm all about tiny batches and I can't put down The New Preserves. Flipping through the Complete Book of Small-Batch Preserving as well.

    I'm with Ashley. I wish her book was out, too!

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  8. julia & nikki - you both are so welcome.
    and nikki i can't agree with you more - i cannot wait for ashley's book(s) to come out!

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  9. Well I'm waiting for my DH to snap a pick for me because.....I made 4 pretty pints of pickled carrots TODAY! These are relatively simple, pickling spice, sugar, vinegar and carrot sticks...wa la!

    Note to self, and maybe others, do NOT help push a carrot through the mandoline with your finger.

    Can't wait to try another recipe.

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  10. Ok, now you have me thinking... I experimented last fall with carrots BEFORE I knew this. In trying to come up with a local restaurant's pickled carrot recipe, I made a few pints each of DELICIOUS dill carrots and (not our favorite) sweet carrots using the same recipes that I use for cucumbers & zuchinni pickles. I did water bathed them but now I'm wondering about the 'acid' thing... Is there any way to know for sure?? THANKS for making this so understandable! :)

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  11. melanie- unfortunately, the only way to know for sure at this point is to get an accurate testing of the pH level. for that you would need a pH meter or strips.

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  12. Nice new lyrics, Tigress! I like. And thanks for the concise botulism information. Looking forward to this month's round up!

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  13. Hey, Tigress! Thanks to the terms of the Can Jam, I've discovered that I can schedule the date of publication on my blog - just never noticed before.

    I had some trouble re-finding the Doris and Jilly post about the rules after you posted about Big Bad B. Can you maybe keep a link to the rules near the top of each month's page?

    Thanks; having fun!

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  14. Melanie: Last year I canned tomatoes and later learned that some varieties might not be acidic enough to prevent the growth of botulism. On the CDC website they state that, when in doubt, boiling for 10 minutes will destroy the botulin toxin. Of course, this is easier done with tomatoes (I just made a big pot of sauce) than with carrots but is good to know. Maybe you could be creative with your pickled carrots and boil them down into a chutney or relish.

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  15. http://winebookgirl.blogspot.com/2010/02/february-is-for-carrots.html

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  16. http://mimisbooks.blogspot.com/2010/02/let-wild-carrot-canning-rumpus-begin.html

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  17. Great, informative post, thanks. I'm wondering how head space affects the botulism question? I have a friend who pickled beets (similar, I believe, to carrots in their low-acid status) but in several of his jars (1 L Mason jars) the beets are an inch or more above the surface of the brine and an inch or more from the jar top.

    All of the jars sealed properly so I guess I'm wondering if the pseudo-vaccuum above the brine is better, the same, or worse for botulism than a properly high-acid brine? Should he be concerned?

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  18. hi david - from what i understand, even though we're always trying to avoid having those jolly tops of the veggies we're pickling from poking out of the liquid because they're not particularly attractive and can even discolor, it's not a safety hazard. that said, if the beets are an inch from the surface of the brine and an inch from the top, there is too much headspace. while they may have sealed now, the seal may not last so i would go ahead and eat the ones that are like that first rather than having them hang around.

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  19. Great post! Thanks for making it all so clear... but l am starting to think that I might just make coleslaw with those carrots and stick to preserving the fruit. LOL!

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  20. anna maria - no, don't be afraid of it, just follow a reputable recipe! :)

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