# Why doesn't Coke dissolve the aluminum can? **URL:** \ **Category:** Cecil's Columns/Staff Reports\ **Created:** [November 6, 2002, 5:32pm UTC](https://boards.straightdope.com/t/why-doesnt-coke-dissolve-the-aluminum-can/135580 "2002-11-06T17:32:34Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![elfoldo](https://avatars.discourse-cdn.com/v4/letter/e/e47c2d/32.png) [@elfoldo](https://boards.straightdope.com/u/elfoldo)\ **Post date:** [November 6, 2002, 5:32pm UTC](https://boards.straightdope.com/t/why-doesnt-coke-dissolve-the-aluminum-can/135580/1 "2002-11-06T17:32:34Z")
Cecil says that the reason that ketchup dissolves aluminum foil is that ketchup is acidic (3.85). Then he says that Coke is even more acidic at 2.7. But Coke is packaged in an aluminum container! Why doesn’t the can melt? ---
**Author:** ![Nametag](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/nametag/32/406_2.png) [@Nametag](https://boards.straightdope.com/u/Nametag)\ **Post date:** [November 6, 2002, 6:43pm UTC](https://boards.straightdope.com/t/why-doesnt-coke-dissolve-the-aluminum-can/135580/2 "2002-11-06T18:43:04Z")
Soda cans are lined. ---
**Author:** ![Arnold\_Winkelried](https://avatars.discourse-cdn.com/v4/letter/a/3d9bf3/32.png) [@Arnold\_Winkelried](https://boards.straightdope.com/u/Arnold_Winkelried)\ **Post date:** [November 7, 2002, 3:15am UTC](https://boards.straightdope.com/t/why-doesnt-coke-dissolve-the-aluminum-can/135580/3 "2002-11-07T03:15:44Z")
Welcome to the SDMB, and thank you for posting your comment. Please include a link to Cecil’s column if it’s on the straight dope web site. To include a link, it can be as simple as including the web page location in your post (make sure there is a space **before** and **after** the text of the URL). Cecil’s column can be found on-line at this link: [Why does ketchup dissolve aluminum foil? (25-Jun-1982)](http://www.straightdope.com/classics/a1_121a.html) * * * moderator, «[**Comments on Cecil’s Columns**](http://boards.straightdope.com/sdmb/forumdisplay.php?forumid=1)» ---
**Author:** ![Arnold\_Winkelried](https://avatars.discourse-cdn.com/v4/letter/a/3d9bf3/32.png) [@Arnold\_Winkelried](https://boards.straightdope.com/u/Arnold_Winkelried)\ **Post date:** [November 7, 2002, 3:17am UTC](https://boards.straightdope.com/t/why-doesnt-coke-dissolve-the-aluminum-can/135580/4 "2002-11-07T03:17:33Z")
A short description of [How Cans Are Made](http://www.canmakers.co.uk/education/how_cans_are_made.asp). ---
**Author:** ![friedo](https://avatars.discourse-cdn.com/v4/letter/f/8edcca/32.png) [@friedo](https://boards.straightdope.com/u/friedo)\ **Post date:** [November 7, 2002, 6:45am UTC](https://boards.straightdope.com/t/why-doesnt-coke-dissolve-the-aluminum-can/135580/5 "2002-11-07T06:45:45Z")
Believe it or not, the Master has written about this very issue: [http://www.straightdope.com/classics/a5\_222a.html](http://www.straightdope.com/classics/a5_222a.html) ---
**Author:** ![Arnold\_Winkelried](https://avatars.discourse-cdn.com/v4/letter/a/3d9bf3/32.png) [@Arnold\_Winkelried](https://boards.straightdope.com/u/Arnold_Winkelried)\ **Post date:** [November 7, 2002, 10:14pm UTC](https://boards.straightdope.com/t/why-doesnt-coke-dissolve-the-aluminum-can/135580/6 "2002-11-07T22:14:30Z")
I was just about to say that! ---
**Author:** ![Fishhead](https://avatars.discourse-cdn.com/v4/letter/f/9f8e36/32.png) [@Fishhead](https://boards.straightdope.com/u/Fishhead)\ **Post date:** [November 9, 2002, 6:12am UTC](https://boards.straightdope.com/t/why-doesnt-coke-dissolve-the-aluminum-can/135580/7 "2002-11-09T06:12:00Z")
Thanks. I can’t usually get the dope’s search engine to work for me, so appreciate the info. It’s something I’ve often wondered about. Interestingly, the link to the canmaker’s web page in the UK said the coating was a lacquer, and Cecil mentioned a “light plastic” compound. I’m not sure if the definition of lacquer can include plastics or not, and the two sites are from different countries, (so I’m not saying Cecil is wrong), but I think I’m going to do a little more research webwise on what the actual coating is, what kind of plastic or whatever. I guess I’ll post it here if I find anything. ---
**Author:** ![Fishhead](https://avatars.discourse-cdn.com/v4/letter/f/9f8e36/32.png) [@Fishhead](https://boards.straightdope.com/u/Fishhead)\ **Post date:** [November 9, 2002, 6:24am UTC](https://boards.straightdope.com/t/why-doesnt-coke-dissolve-the-aluminum-can/135580/8 "2002-11-09T06:24:52Z")
This from here: [http://es.epa.gov/techinfo/research/reduce/rrel508.html](http://es.epa.gov/techinfo/research/reduce/rrel508.html) _Liquid hazardous wastes are generated from the painting and inking operations in the form of excess paint and ink cleaned from machinery. Most of the paint wastes are from the water- based paint used to coat the inner can surfaces. Although the paints and inks are water-based, they contain ethylene glycol monobutyl ether, n-butyl alcohol, dimethylethanolamine, and 2-butoxyethanol; the paint wastes are considered hazardous and are shipped to a hazardous waste disposal facility._