Food scientist extraordinaire Harold McGee explains that you can age certain canned goods to positive effect.

There must be many such minor treasures forgotten in kitchen cabinets and basements and emergency stashes all over the country. My own supply still being fairly young, I consulted the eminent Sacramento grocer Darrell Corti, who very kindly shared a few items from his storeroom. I compared a new can of French sardines in olive oil with 2000 and 1997 millésimes. The brands were different, and so were the size and color of the fish and the quality of the olive oils. That said, the young sardines were firm and dry and mild; the older vintages were fragile to the point of falling apart, soft and rich in the mouth, and fishier in a good way. A 2007 (70th anniversary) can of Spam was also softer than the 2012 (75th), less bouncy and less immediately and stingingly salty, though the aromas were pretty much the same. Some Corti Brothers mincemeat aged for a year under a cap of suet was delicious, its spices and alcohols seamlessly integrated. A five-year-old tin of French goose foie gras: no complaints. Two vintages of Corti Brothers bergamot marmalade: the older noticeably darker in color and surprisingly reminiscent of Moroccan preserved lemons. And 3-year-old Cougar Gold—still moist and not as sharp as open-aged cheddars—was deeper in color and flavor than the yearling version, with a touch of caramel and the crunchy crystals that are the hallmark of hard aged Goudas.
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I’ve found that braising cans change the flavors and textures within, but unpredictably so. It doesn’t seem to do much for sardines, but tuna in water loses its beefiness and becomes more pleasantly fishy and also a little bitter, while tuna in oil somehow gets more meaty and less fishy. Like its aged version, can-braised Spam takes on a softness that’s especially nice when you fry the surface to a crunchy crust.
I don’t recommend cooking foods in the can as a routine thing. Cans have various linings that may gradually release unwanted chemicals into foods, and this process will also accelerate at high temperatures. But it’s a way to explore how canned foods are capable of developing.

Amazing. Coming soon to a pop-up restaurant near you: a vertical tasting of 1988-1993 canned Spam. Excuse my while I go sous-vide a can of Chicken of the Sea.

[via The Browser]