When I started drinking craft beer a decade ago, there was a vigorous debate happening: Bottles or cans? Is the ultimate answer to that question about mere preference? Portability? Sustainability? Quality? At the time, there were relatively few craft beers in cans, and there was a lot of skepticism about them. To some extent, cans were still considered containers for cheap beer, and canned craft was more novel curiosity than anything.
In 2018, it’s a can’s world. Many new breweries today are canning exclusively, and old stalwarts like Sierra Nevada and New Belgium have an abundance of canned craft offerings. Even the beer patriarch of Ohio, Great Lakes Brewing, recently introduced its first cans. But what are the real arguments in favor of cans or their glass predecessors?
For years, one of the central arguments in favor of bottles over cans was glass kept beer tasting better, longer. Many people thought cans made beer taste tinny or metallic, though it’s unclear why. Perhaps it’s the fact that cans were for so long filled mostly with cheap beer that didn’t taste great to begin with. Since American brewers began canning beer in the early 1930s, beer cans have been lined with various substances to keep the liquid from coming in direct contact with the metal, which prevent corrosion and corruption of flavor. Since at least the 1980s, all aluminum beverage cans in America have been lined with BPA, a polycarbonate epoxy-resin that’s run afoul of some controversy in recent years: First created as a synthetic estrogen in 1891, it’s acknowledged to be slightly toxic even by breweries (like Sierra Nevada), who have no choice but to rely on cans lined with the stuff. There’s just no other game in town right now.
So what about the other big beer quality factors: Heat, light and oxygen? Light is a great enemy of hoppy beer, as it oxidizes hop oils and creates that familiar skunky aroma. Brown glass is good at protecting beer from light, but cans, being opaque, are far better. Regarding heat, which is anathema to beer freshness and flavor, cans offer less protection than bottles—glass is a much better insulator than aluminum, so if you shamefully leave your beer in a hot car, canned beer will cook much faster than bottled. When it comes to oxygen, beer cans are hermetically sealed when the lid portion is seamed onto the rest of the can, essentially becoming one airtight unit. Bottles, obviously, are capped, and typically retain more oxygen in their headspace than do cans. That residual oxygen stales your beer faster.
Here’s where cans unquestionably outshine bottles. They’re lighter, easier to transport, faster to cool and unbreakable. You can take them camping, canoeing, picnicking, to festivals, etc., much more easily and discreetly than bottles. And while we’d never endorse such behaviors as the ole slip that can o’ IPA into a koozie and you could probably even drink it in public—it’s a little more subtle and marginally classier than the bag-and-bottle approach. It’s no coincidence that Oskar Blues, one of the first American craft breweries to invest heavily in canning, has deep ties to the backpacking and outdoor-lovin’ culture of their native Colorado Rockies. Cans of their signature Dale’s Pale Ale still bear the signature backpacker’s dictum: “Pack It In, Pack It Out.”
When it comes to taking delicious draught beer with you on the go, glass was for the longest time the best and only option. The 64oz glass growler has indelible iconic associations with craft beer. In recent years, however, many breweries and taprooms have invested in the Crowler (can plus growler). Essentially a 32-oz version of the humble 12-oz aluminum beverage can, a Crowler comes to your local brewery as a headless aluminum tube, which is then filled with beer from the draught faucet just as a normal glass growler would be. A specialized piece of equipment known as a can seamer is then used to then affix a lid to the top of the can, making in an airtight container very similar to a normal beer can. Et voila—draught beer to go that’s much easier to cart around than an unwieldy half-gallon glass jug. Once you pop, however, you can’t stop—or at least, you can’t reseal a Crowler once it’s opened. While with a glass growler you can screw the cap back on, it’s diminishing returns every time, and your beer is still going to go flat quickly.
Historically, one of the strongest arguments for cans over glass has been the cumulative environmental impact. Cans have a smaller carbon footprint, depending on how you measure the proverbial shoe. They are lighter than the equivalent glass containers and thus require less energy to ship them, not to mention the fact that more “flats” (four six-packs in a cardboard tray or one case of beer) can in theory fit on a standard pallet than can bottles, so more can be shipped at once, necessitating (again, in theory) fewer truckloads overall. Additionally, recycling cans is more efficient—cumulative energy savings of 96% when you recycle a ton of aluminum versus approximately 27% for a ton of glass, according to Slate. How far the end product travels to you the consumer matters, as well: "Once a cross-country truck journey is factored into the equation, a bottle ends up emitting 20 percent more greenhouse gases than a can.” In this regard, at least, drinking local can be an uncomplicated good—or at least more carbon-neutral than drinking the equivalent beer from half a world away. When it comes to draught beer to go, glass growlers may have the environmental edge over Crowler cans—you can reuse that half gallon bottle over and over, after all. Just doin’ Mother Earth a solid.
Recycling is a business, and recyclable materials are commodities, and when the price of waste commodities drops, less recycling takes place—though aluminum and glass are somewhat spared from the vagaries of the market by dint of being lucrative enough (usually) to recycle domestically. It remains to be seen how the Trump administration’s proposed aluminum tariffs will affect the bottle versus can equation. Though the tariffs have yet to be actually implemented, the Beer Institute notes that in the wake of the announcement, the delivered price of a pound of aluminum increased some 30%. If Trump’s “good,” “easy to win” trade war is actually prosecuted, bottles could look more and more attractive to domestic brewers—assuming they can afford brewing equipment under the similarly-proposed steel tariffs.