Best Before and Use By are daily mantras; the first focussing on quality, the other a more serious indicator of safety. But when it comes to beer, in particular bottles and cans where labelling is so diverse, sometimes it can be more than a little confusing if like me, you prefer to purchase beer not readily found in large supermarkets. Beers from a startling number of countries are now readily available in bottle or can (if you know where to look), and offer countless options in terms of strength, style and inventiveness, as well as unique and often exquisite labelling or artwork which draw the drinker in. However, this diversity can sometimes bring its own issues, particularly on non-UK products when attempting to decode the product information on the label. To help ensure a consistent experience for all consumers, some breweries use date codes; but because there are no standards or requirements for indicating beer age, each brewery employs its own method for dating its beers. (Regrettably, some foreign breweries don’t offer any date stamps whatsoever, leaving you completely in the dark about the freshness of their products). But is this really an issue you ask? 
Basically, beer is liquid bread, and bottle / can conditioned beer is that artisan loaf that is meant to be eaten right away. With beers going unfiltered, unpasteurized, and still stored more often than not in bottles instead of cans, their shelf life is limited. The longer they stay on the shelf, the less they are like the beer that was originally brewed. For stronger beers, this can often be a good thing, with flavours maturing and mellowing, but for most, oxidation, being light struck, poor storage, and more can turn that beer into a less than pleasurable experience. On cans, most dates are printed on the bottom; on bottles check the neck, bottle top or label. But sometimes, deciphering the age of a beer can prove more difficult than locating it! The most common types of dates are packaging dates (bottled on) and shelf-life dates (best before). However; ‘enjoy by’, ‘consume by’ or ‘sell by’ are also often used. For most beers, the optimum date is 60–120 days after packaging but this can vary based on the style. US production date codes are a whole different animal and use a Julian date which has the following format: For example, the code may be 9340554B14 Which actually means: Position 1 = year (9 = 2009) Position 2, 3 and 4 = day of the year (340 = 340th day) Position 5, 6 and 7 = country code (554 = NZ) Position 8 = filling line (B = filling line B) Position 9, 10 = hour (14 = 2pm) For more info freshbeeronly.com is a handy decoder for US Breweries’ production code dates, or if in doubt contact the brewery direct.
