The latest batch of Stone Brewing's "devastatingly fresh" Enjoy By 4.01.13 IPA hits shelves this week, and the brewers are so serious about the freshness of their beer that they've built an April 1 deadline into the beer's name. But why is it so important for this beer to be consumed within the 35-day freshness window?
Stone packs so much hops into their Enjoy By beer that they will pull it from retailer's shelves 35 days after the beer was bottled to prevent anyone from buying a past-its-prime bottle. While well-brewed beer isn't going to spoil if you leave it sitting around, it is a product that is best consumed fresh, and beer's flavors and aromas begin to degrade just days after being packaged. You may have heard of people laying beer down, wine-like, to cellar, but only a small subset of beer styles will actually improve over time. The vast majority of popular beers, especially anything where the hops take center stage, should be treated more like milk than wine. Keep it cold and drink it promptly.
Time leads to oxidation, and this will dull a beer's flavor. The first casualty will be the prized hop aroma and flavor, then the beer's bitterness will begin to mellow, any spice or flavor additions will fade, and -- in extreme cases -- the beer can begin to develop off-flavors like wet cardboard. Keeping the beer cold will mitigate the effects, but the best defense against fading flavor is to avoid storing beer for much longer than a month or two.