Q: I want to do some canning, but aren’t there nasty chemicals in the lids?
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A: I come from a short line of non-canners. My grandmother didn’t can. My mother didn’t can. My aunt, on the other hand, had a delectable pantry of homemade pickles and French-Canadian relishes that sparkled like jewels to my hungry young eyes.
Now after decades of marginality, canning is sexy again. Of course just as more and more newbies are being seduced by the charms of preserving our local bounty, we’re realizing the tools of the trade aren’t all without worry.
While glass jars are beautifully inert and easily recycled, the damn lids are causing problems. Just when you thought you were getting away from chemicals leaching from tin cans by reaching for glass, yes, it turns out lids for home canning are lined with the same “food-grade epoxy” that’s mostly estrogen-mimicking bisphenol A (BPA).
There hasn’t been any formal testing on home canning products, but when Consumer Reports tested foods packaged with that epoxy liner last year, they found significant levels – up to 134 parts per billion – in nearly all canned goods.
Actually plenty of food in epoxy- free plastic containers still contained BPA, though at much lower levels. Even cans with BPA-free liners had trace amounts. (Eden beans had 1 ppb.) Interestingly enough for the lid-concerned, a plastic container of ravioli with a peel-back metal lid had more BPA than the canned version.
I’d hazard a guess that if you sterilize/boil your lids separately from your glass jars and make sure your jars stay upright on the shelf before you crack em open, there’s a good possibility their contents will have much lower levels of bisphenol A than a tin can of Zoodles that’s been shaken left, right and centre on conveyor belts and truck rides on its way to store shelves.
Don’t fill your jars to the brim either.
If you’d prefer to be 100 per cent BPA-free, order special lids that clearly say they don’t contain BPA. Pretty much the only option available right now is made by Tattler. Their lids are reusable (unlike 99 per cent of canning lids used today, adding to their green value) and are made with polyoxymethylene copolymer, aka acetal copolymer. They don’t contain BPA or phthalates and pass all food contact standards (reusablecanninglids.com).
High-profile canners like Marisa at foodinjars.com are big fans of the product for both water-boiling and pressure-canning methods. They note that to get a good seal you must, after putting the lid and band on, unscrew the band a quarter of an inch for air to escape during processing, then give the lid a good tightening when you remove the jar from the canner.
The only potential problemo lies with the rubber gaskets used to make the seal on these and on glass-lidded jars. Chemical and Engineering News (an American Chemical Society publication) calls rubber “arguably the most problematic source of migrating chemicals,” commonly leaching chems like N-nitrosamines, which can be carcinogenic.
Weirdly, the U.S. Food and Drug Administration only clearly restricts nitrosamines from baby bottle nipples. But the good news is the rubber industry has figured out ways to block or significantly reduce leaching in food-contacting rubber.
The people at Tattler say their rubber is all food-grade, and I’m not sure I’d buy rubber-ringed jars from a cheap dollar store.
Once you’ve got your gear sorted out and ordered, get canning in a hurry while you’ve still got a couple weeks left of harvest season.
If you’re looking for creative ideas on what to do with seasonal ingredients, snoop around on some top blogs like tigressinajam.blogspot.com (hello, pumpkin marmalade!), foodinjars.com (love the pickled green tomatoes), canningacrossamerica.com (check out the organic crabapple jelly and cabbage kimchi) and my own canning guru’s vanilla-pear butter (awesome with local cheeses) on digginthedirt.ca.
Happy canning!
Send your green queries to ecoholic@nowtoronto.com
