7

I understand that carbonation might not last forever, and diet beverages don't taste good after a period of time, but I've always believed that the expiry date on the can doesn't matter, provided it's sealed and still carbonated when you open it, it should be safe to drink. I think a lot of people feel that non-obvious expiry dates (ex. dairy and meat obviously do expire) are a ploy to sell more products.

I've heard claims (see comments for some links) that the can or lining on the inside of the can will be eaten away over time causing carcinogens to be released into the liquid. I'm skeptical that the liquid itself would expire, but what about the aluminum can, does it expire?

wweicker
  • 171
  • 1
  • 5
  • 3
    acid can eat away aluminium – ratchet freak Nov 14 '11 at 22:30
  • Related question: http://skeptics.stackexchange.com/questions/6469/why-do-mineral-water-bottles-have-an-expiry-date - I note the community voted that one off-topic. – Oddthinking Nov 15 '11 at 03:57
  • Is regular (non-sugarless) cola/pop/soda safe to drink? – Randolf Richardson Nov 15 '11 at 07:41
  • Is this claim notable? Can you provide proof of that, please? – Sklivvz Nov 15 '11 at 10:34
  • This post claims "Aluminum can manufactures line the interior of the cans with a thin coating of plastic to prevent aluminum from leeching into the food. Unfortunately, one side effect of including a plastic lining in aluminum cans is that consumers can be exposed to toxic levels of BPA." http://www.livestrong.com/article/259503-the-disadvantages-of-aluminum-cans/ – wweicker Nov 15 '11 at 17:27
  • This post claims "Any foodstuff (beer, soup, vegetables, pop, gravy, etc ...) that comes in a can these days has an epoxy liner which contains the controversial BPA — a chemical linked by some studies to cancer, infertility and obesity — which leeches into liquids in incredibly tiny amounts." http://voices.idahostatesman.com/2010/06/04/porr/beer_cans_and_bpa – wweicker Nov 15 '11 at 17:29
  • Unsubstantiated: "Typically, these expiration dates are, in fact, 'best by' dates — the date you want to drink it by for optimal flavor." http://www.tampabay.com/features/humaninterest/article659188.ece – wweicker Nov 15 '11 at 17:45
  • 2
    and worse, any claim using the word "controversial" is by its very nature fearmongering and not to be trusted. – jwenting Nov 16 '11 at 11:04

1 Answers1

2

All soda cans are treated with a coating on the inside, exactly in order to prevent the contents from having any corrosive effect on the can itself.

The inside [of the can] also gets a treatment: a spray-coated epoxy laquer separates the can's contents from its aluminum walls.

So, I'll say no, the contents aren't corroding the can and thereby causing an unhealthy result. Expired contents can become unhealthy for other reasons though, regardless of what container it was stored in.

Oddthinking
  • 140,378
  • 46
  • 548
  • 638
Torben Gundtofte-Bruun
  • 971
  • 1
  • 6
  • 17
  • Expiration dates are usually a quality issue first, then a safety issue. That's why they usually say "best by [date]" instead of "safe until [date]". Only for food especially prone to spoiling is the safety date more of a concern than the quality date. –  Jul 09 '16 at 14:51