Dear Mr. Wizard,

Over the years I have collected a variety of rare bottles of beer that I am currently storing on the bottom shelf of my refrigerator for consumption in the future. Some of these bottles, such as the Samichlaus and Stille Nacht, may be in there for a couple of years before I get around to drinking them. Is this the best place to be storing them? Should I also wrap them in paper to keep the light from the refrigerator from spoiling them? I also have a room in my basement that is dark and usually stays around 50-55 ºF (10–13 ºF) in the winter and 65 ºF (18 ºC) in the summer — would this be a better place to keep them? Finally, is there a way to determine by alcohol content or beer type what beers will last longer in storage than others and how long they will last?

Josh Davis
Boalsburg, Pennsylvania

Mr. Wizard replies:

This question reminds me of an article written by G. Bruce Knecht and published in the Wall Street Journal on January 30th. In his simple-minded article, Mr. Knecht criticized breweries that use cryptic code dates on their bottles and suggested that beer should have clearly printed expiration dates like bread and milk. “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.”

Something about this declaration triggered my gag reflex and pointed me toward my kitchen in search of expiration dates on the various items in my freezer, refrigerator and pantry. I left my kitchen and went to a grocery store for a more complete survey of food packages. As I expected the Wall Street Journal author used a bit of hyperbole in his opening paragraph. I found many “best before” dates and some “sell by” dates on the items in my kitchen and at the store, but no “expiration” dates. I even found some packages with dates stamped on them that are clearly in the future with no explanation of the date . . . consumers are left to interpret these dates as either best before or expiration dates and if the product sits around long enough the same stamp may appear to be a packaging date. One can even had a “born on date” on it and for a moment I thought perhaps I was supposed to burp it!

The shelf life of beer, like food, is hard to predict because several factors contribute to its deterioration. Furthermore, many food products can be safely consumed when their freshness begins to fade and the point in the decline of freshness where a food is no longer palatable is a matter of opinion. Some items — e.g. bread — get old and stale to the point of being totally disagreeable and then become the ideal ingredient for something truly delicious like a crouton.

Unfortunately, beer is not as forgiving as bread and when beer is passed its prime, it just tastes old and the consumer wishes they had consumed it earlier. I am, like Mr. Knecht, simple-minded but I view beer storage from the perspective of the brewer. When most beers leave the brewery they are ready to be consumed . . . otherwise no well-run brewery would put the beer out on the shelf to be purchased. In fact, the freshness clock begins ticking for most beer at the time of bottling. All the nurturing that the brewer feels is required is complete and it’s time to bottle and drink the darn stuff!

The rule for these types of beers is to get ‘em in the fridge and drink ‘em as soon as possible because for certain, nothing good will happen to the beer by hanging on to it. The exceptions to this rule are with bottle-conditioned beers and some high alcohol beers. Obviously, with bottle-conditioned beers, the beer must carbonate in the bottle and this takes time. Meaning the beer improves for some time and then begins its downhill slide.

Some high alcohol beers improve with age and much of the improvement with these beers is actually a product of oxidation. Many aged big beers, such as barleywines, take on flavors reminiscent of sherry (that also gets much of its flavor from oxidation). I know of no rule of thumb matching the alcohol content of beer with its ability to age gracefully. I typically try to imagine how a beer would taste if it was “rounded out” by age. Many strong beers that do seem to benefit from age are big, malty and balanced by assertive hop bitterness when young. I think this is why many strong ales seem to improve with age. Strong lagers get their aging in the brewery and, to my palate, are best consumed when fresh.

The only reliable way to monitor a beer and determine when it reaches its peak is to taste it. This requires a whole bunch of the same beer and persistent quality control. Meaning you have to drink your stash and take notes on its progress. Ideally you will note the point when the beer is ever so slightly passed its peak and you can finish off the remainder before the flavor really begins to suffer. The same is true of many wines that are held in storage and many a collector has cursed himself for holding on to an excellent bottle of wine too long.

Aside from microbiological spoilers, the main things to keep away from beer during storage are oxygen, heat and ultraviolet light. Your question is about bottled beer and there is not much you can do to keep oxygen out of the beer other than not storing it for really long time periods. Remember that oxygen migrates into beer bottles through the crown liner and that carbon dioxide migrates out through the same line over time. Some liners contain molecules that scavenge oxygen, but you cannot differentiate these by sight.

Heat speeds up all chemical reactions, so whatever is going to happen to your precious bottle of brew over time will simply happen quicker as the storage temperature is increased. In my opinion, the only time a bottle of beer should be stored warm is if it is being bottle conditioned. Once the conditioning phase is complete, storing it cold will prolong its age. If you store your collection in your basement, aging will simply accelerate, especially in the summer when the temperature climbs to 65 ºF (18 ºC). I always store beer cold! Finally there is UV light, the causative agent of skunky beer. Brown bottles do a very good job of filtering UV light. I have had skunky beer from lightly tinted brown bottles, but that has been a rarity for me. If you are concerned about the bottle color, a bag will work great to protect your prized beer from light.