Beer — an alcoholic beverage brewed with hops, malt and barley; once referred to by Keats as “sweet liquid bread” — has a half life of about three months. Six months from the date of brewing, beer turns from inebriating mana into hobo swill. Then why is it that most American beers do not display their expiration dates, so consumer’s can pick the freshest brew possible?

According to this article, beers actually do — it’s simply written on each bottle in a secret code to confuse alcohol-addled consumers.

A loaf of bread has it. So does a carton of milk. But if you’re looking for the expiration date on a bottle of beer, forget about it – for many brewers, that information is a closely guarded secret.

There are now more bottles of beer on the store wall than ever – more than 2,000 domestic brands alone – making it harder for both stores and consumers to steer clear of the stale stuff. Age is critical: Nearly all beer begins to deteriorate before it even leaves the plant, partly due to oxygen in the bottle, and many experts say most brews are well past their prime after six months.

To identify when bottles and cans need to be yanked from the shelves, many brewers imprint them with cryptic letters and numbers that distributors can translate. The trouble is they look more like hieroglyphics to beer drinkers, and most makers don’t decipher them for consumers. But with the help of industry insiders and analysts, we cracked the codes, studying bottles purchased across the country to determine the key dates for 18 big brews.

The way the code works is this. Letters from A-M represent the month of the year. The next four digits are the day and year the beer was first brewed, and the last two letters are the state code where it was brewed. So you may want to stay away from that fifty cent close-out special at the local liquor store marked M0787DE. Oddly enough, Irish brews have clearly marked expiration dates… and our local off-license sells a variety of off-peak beers in foul-smelling wicker baskets for discount prices. Hobo’s delight.

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