Citric acid sounds like something the villain would use in a Batman comic, doesn't it? And yet it turns up in ingredient lists all the time, even those of so-called organic, all-natural, healthy products. Heck, we've even got a bag of it in our cupboard right now, and it's purpose might surprise you!
Although the process of extracting it is rather scientific, the acid itself is a natural, organic, non-test-tube product. The same citric acid listed in the ingredients for tomato sauce is what makes fruits like lemons and limes taste sour! It was originally produced by dehydrating and crystallizing lemons, though it was later discovered that certain strains of mold (like Penicillium) produced it much more efficiently.
As you might expect, one of the biggest uses of citric acid is to make things taste sour. It's found in sour candies, sodas, juices, and many pre-made foods. It's also a fairly efficient natural preservative and color-enhancer, which is why it's listed as an ingredient in many canned and preserved goods.
As for the citric acid in our cupboard? We keep it around for making cheese! Since it's so concentrated, citric acid is much better at getting milk to separate than straight lemon juice. In our research for this post, we also discovered that citric acid can be diluted in water and used as a household cleaner - maybe we'll try that next!
Related: Good Question: Labeling for Transfats and Partially Hydrogenated Vegetable Oils
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Hmmm, never thought of using it as a cleaner. I too have a bag of it in my cupboard for making cheese :-)
So where the heck do you BUY it? I've needed to get it for canning tomatoes, but I cannot find it at all anywhere.
It's also used a lot as a preservative - I've used it when canning my own tomatoes and sometimes apples to increase acidity in products for water bath canning. It's also the essential ingredient in fruit fresh that keeps fruit from browning.
empresscallipygos - I never have bought it myself, but I believe you can buy citric acid from the chemist.
Citric acid can also usually be found in the bulk spice section at any store with a good bulk section. I recently discovered that my local food co-op carries it, and plan on getting some for this summer to use for canning. As kestrel pointed out above, it's the main ingredient in FruitFresh, and we used so much of that last summer canning applesauce that I figure buying bulk citric acid will be far cheaper.
Citric Acid can also be found as "SOUR SALT" in the Kosher food section of the grocery store.
Also can be found with canning supplies - jars, lids,... I believe Ball that makes jars and such sells in under their trade name. Also, seems like there was a brand called 'Fruit Fresh' or the like, that was sold and intended to keep fruit from browning.
oops, I looked up the Ball product 'Fruit Fresh' it's not pure citric acid - ingredients listed were:
Ingredients:Dextrose, Ascorbic Acid (Vitamin C), Citric Acid, Silicon Dioxide (Anti-Caking).
I also use it in some Indian food.
....Indian food....oh, bingo! I know where I can get it now (read: the huge Indian market I know about). Thanks.
the beer making supply shop carries large quantities of citric acid, as do several natural food stores.
We use to make sherbet with it in high school science.
Yes, Indian grocery stores--that's where I get mine.
I learned it's used in a lot of Syrian food in cases where you might use lemon juice, when lemon is out of season. And restaurant chefs like it because it holds its flavor in a way that lemon juice doesn't.
Last summer, I added citric acid to iced tea--delish.
I've used both citric acid and vitamin c powder to sprinkle over cut up peaches before I ziploc and freeze them over the winter (can't be bothered to can in my teeny apartment).
I've always gotten it at my local health food store, although I'm happy to have the Indian grocery store tip! I buy all my spices in bulk there, and it's so much more cost effective.
A spoonful of citric acid boiled in the electric kettle descales it in minutes, without any unknown chemicals working away at it. It always seems like magic to me.
@yaaronet Genius!! My kettle is in a sad state and short of going in with a butter knife and hacking away I was out of ideas.
Just found someone on a message board saying that he got it quite cheaply (3euro/kilo) at a shop that sells supplies for winemaking, so there's another possible location!
I got mine from moutain rose herbs online. I buy alot of bulk herbs from there.
@lemongrove - Glad to help! My favourite part is watching it bubble at the bottom and eat away at all the disgusting scaley bits...
I use it to make elderflower cordial...yummy I think I bought it at healthy/organic food store it is in a 1 lb foil bag, Frontier brand, and have just noticed it is 'non-irradiated'...phew, think that must be a good thing!
I bought my citric acid from a cheese making website. Just google one and they will offer it in bulk.
Btw, I think citric acid is also used in vodka making (along with glycerides) to make it smoother.
My Dad used to sprinkle it on sliced apples for our school lunches to keep them from turning all brown before lunchtime.
A 1/4 cup in the toilet bowl gets rid of the mineral residue around the water surface and clears up the debris clinging to the porcelain better than the toilet bowl cleaner. Let it sit for 15 minutes and brush off the scale...same idea as the coffee kettle above.
Citric acid IS a villain to some folks who get migraines. It is on the long list of potential food-related triggers. And it really is everywhere due to its use as a preservative. Anyone have non-citric acid/citrus alternatives to natural food preservation?
I'd love to find a guaranteed citrus sourced citric acid, as it can be produced from both corn and soy as well as fruit, and I have a corn allergy and have a friend with a severe soy allergy. There are enough trace proteins remaining in soy/corn based citric acid to trigger reactions in the most sensitive of us, so it's a shame that the source material isn't required in the labeling.