If you didn't like reading that milk shipped to Hawaii supermarkets is not refrigerated, you're not going to like learning that there is formaldehyde in your canned beer. Not just in Hawaii, but across the country.

Worse, beer manufacturers say that you (collectively) wouldn't like your beer unless it had that characteristic whiff of formaldehyde flavor. So they make sure that it does, "or else people aren't going to accept it." In fact, referring to the emulsion used to wash the can and impart that special scent, an article in Notre Dame Magazine  states that in the manufacture of the cans, "Extensive tests are run to make sure the lubricant and additives taste like formaldehyde." The article begins:

What's in those cans beside beer?

It can now be revealed why bottled beer and beer from a tap tastes different from beer in a can.

Be forewarned: if you're a six-pack enthusiast, you're not going to like the explanation.

When you sip a can of your favorite brew, you are savoring not only fermented grain and hops but just a hint of the same preservative that kept the frog you dissected in 10th-grade biology class lily-pad fresh: formaldehyde.

What is formaldehyde doing in beer? The same thing it's doing in pop and other food and drink packaged in steel and aluminum cans: killing bacteria. But not the bacteria in the drink, the bacteria that attacks a lubricant used in the manufacture of the can.

Read the article. It doesn't get better, it gets worse. The article is a good explanation of can making, though. And at the very end it confirms what I've long suspected--that the can costs many times more than the cost of the beverage inside it.