Anyone that is into properly aged beer, whether they dabbled with a 6-month-old stout or curate a beer cellar going back decades, can tell you the exact beer that started it all for them. For me, it was a 2009 Avery Mephistopheles I drank in 2012. The velvety mouth feel, mellowed booze, smoothed out bitterness, and heightened caramel made it a near perfect experience.

Since then, I’ve cultivated a small, but hand-picked, group of beers that I look forward to diving into soon, because really what’s the point of aging beer if they’re just going to be unearthed in the year 2145 by the roving hordes of Lord Humongous and converted to fuel. I intend to enjoy them while civilization and I still stand.

With that in mind, I delve deeper into my hobby of not drinking beer and secluding it in the dark like Paul Dano in Prisoners, and turn to the studies of smarter men than me to determine just what is going on inside that bottle. To apply this knowledge, I also drink an 18-year-old Barleywine to taste nearly two decades worth of science. Here’s what I found.

To learn about the science of aging beer, go to She Aged You with Science section.

To skip to the old beer, go to Barleywine of Brewing Past section.

To sneak into the witch’s hut, go to page 41.

She Aged You with Science

Anyone that’s done research into the technical aspects of aging beer has probably noticed a wealth of overly-complicated scholarly articles that spend 30 pages analyzing a single chemical compound of beer, but fail to provide consumer level context as to how it translates to our taste buds. However, there are at least a few helpful reports for us beer drinkers.

One that is frequently referenced is the 1977 report from C.E. Dalgliesh, former Brewing Research Foundation director. While there is plenty of merit to Dalgliesh’s findings, the report took a one-size-fits-all approach, looking at aged beer (specifically an ale) in the broadest of terms and noting general beer changes without real regard to beer style or aging conditions.

In a 2006 report, the quality assurance obsessed Bart Vanderhaegan aged several Belgian beers of varying qualities (dark, lager, high ABV, etc.) and measured 15 compounds multiple times over a one year period. A panel of expert tasters also sampled each at the time of measurement, offering their observations.

If we take the generalities of the Dalgliesh report and marry it to the specifics of Vanderhaegan’s findings, we can get a better picture of time versus beer flavor. As there are already plenty of articles the get into the chemical compositions and “nitty-gritty” of these studies, I’ll try to sprinkle my version with the slightest dusting of science, but at a level that is useful to beer drinkers.

For a frame of reference, we can look at Dagliesh’s data, as shown in the graph above. Based on this, the general progression of aged beer flavors can be described thusly:

As time increases, the following elements INCREASE:

Ribes (catty, or as the royals say, cat pissy notes)

Sweet smells and tastes, such as toffee

“Cardboard” smell/flavor

Diacetyl (buttery slickness)

As time increases, the following elements DECREASE:

Ribes (cat pissy notes)

Bitterness

Esters (fruity aroma/flavor)

I think this confirms what many of us have experienced to varying degrees in our aged beers, but let’s look a little closer and highlight some causes for these changes. To a large degree, oxygen can be blamed for a lot of it. Like just about all of it. It is the enemy of hop flavors and aroma, leading to the sharp decrease over time shown in the graph. I’ve laid this issue out in greater detail in my Why Not of Aging IPAs article and followed it up with Stone’s Enjoy By Enjoyed Later article applying the theory to several past date Enjoy Bys. I suggest checking those out if want to know more info. (spoilers: if yummy hops matter to you, don’t age it).

You’ll also notice that ribes, a quality associated with blackcurrant, is on both lists. Ribes sharply increase with a small amount of age, but take a dive off the moon as it continues to mature. The ribes rise is partially attributable to the oxygen in the bottle headspace. A deeper look into the research shows the peak and downfall of ribes takes a matter of weeks and will mostly like be gone in half a year’s time, making it only a minor nuisance to beer hoarders. There is a great article to reference if you want more detail here.

Another element to consider is why aged beers get sweeter with time. After performing a wealth of research, I have determined this: it’s fucking complicated. From what I gather, some of it comes down to Strecker aldehydes, like phenylacetaldehyde, a compound that occurs naturally in apples, flowers, raisins and so forth, which contributes a honey and rose like taste/aroma. The phenylacetaldehyde in a beer increases over time due to the degradation of L-phenylalanine, formed during the brewing process. Other aspects of Strecker aldehydes contribute a whole wealth of chemical changes, for instance the dreaded (E)-2-noneal, a compound that results in the flavor of cardboard. It gets far, FAR too complicated for an article like this, but at least it provides some minor insight.

Another contributor to sweetness comes with the increase of diacetyl compounds (buttery slickness and toffee/butterscotch flavors). There are many reasons for an abundance of diacetyl in a beer, from bacteria to the over production of diacetyl during the fermentation process, but in aged beer, it can come from alpha acetolactate, which coverts into diacetyl over time due to “chemistry.” Without active yeast to turn the diacetyl into a flavorless compound, it can overrun the beer.

All of this barely scratches the surface on the science of aged beer and probably has chemists on the verge of suicide, but if you take away anything, let it be this: The warmer the beer is during storage, the quicker the chemical actions I discussed will occur. So a beer aged at room temperature for 2 years can potentially show greater effects of aging, both good and bad, than a beer kept at cooler temperatures that is almost twice as old. Keep in mind the conditions around your aging bottles when you are deciding how long to hold it. Which brings us to a Barleywine that is almost old enough to start drinking other beers.



Barleywine of Brewing Past

Now, I take the science of aging and apply it to some real world experience. To this end, I was able to secure a Barleywine that made it to the tender age of 18 years, old enough to legally marry in most states without parental consent. In this case, it will be married to my liver, but it’s a marriage not made to last. Regardless, this glass time capsule is a rather special beer now and not just because it was brewed the year I graduated high school.

To my detriment, I haven’t had the chance to try an un-aged version of John Barleycorn, so I can’t make any direct comparisons. If I thought ahead I probably could have secured one, so that’s on me. On the plus side, I brought this to a local bar and shared it with the bartender and some of the regulars to spread the love and get more than just my opinion.

John Barleycorn 1997

Brewery: Mad River Brewing

Style: Barleywine

ABV: 8%

Cost: No Idea then or now (bought in a larger group of bottles)

Glassware: Snifter, Teku

Temp: 55°F

Availability: Not so much

Purchased @: Sabatini’s Pizza

Appearance: The thickest, most luxuriously fluffy head to ever be poured is a description that no one will ever use for this beer. It’s a flat pool of oil that slicks around in the glass. The color is amber gold with a deeper tawny brown on a full glass pour. There is a mild cloudiness that reminds me of an unfiltered homebrew with some chill haze, but the clarity is surprisingly intact and not as pond murky as I anticipated.

Aroma: The aroma isn’t particularly strong, limping out of the glass and into my nostrils, but there is a burnt/chemical smell that reminds me of a freshly opened pack of rubber bands (or “gum” bands for you heathens in Pittsburgh. Go drink your pop!). This mixes with a bready caramel sweetness that is odd, but not entirely unpleasant. The aroma lacks depth or subtleties, although they may not have been there to begin with.

Taste/Mouth Feel: This blast from the past has a ridiculously slick, buttery mouth feel, like a Slip ’N Slide (by Whamo) coated in vegetable oil. This doesn’t translate to a syrupy thickness, but more a medium body with a bit of weight. The flavor continues the voyage into the unknown with a distinct tart/sour caramel apple and cherry that finishes burnt raisin bread. Some astringency is there, but fairly low. Sandwiched in the middle of the sweet and sour is a flat malt element that is too light and simple to yield deeper layers of complexity.

While these flavors are not unheard of in beer, the level of sour in a Barleywine does confuse the palate. Without a fresh version for comparison, I can’t speak to specific changes, but this is easily the most unique Barleywine I’ve ever had.

Age Analysis: Let’s consider our flavor versus time discoveries to determine what happened here. Just about everything seems to be in line with the reports I read. Even if this beer originally had the ribes quality, as highly unlikely as that is, it has long since aged away. While I wouldn’t necessarily consider the taste to be cardboard, the malt was definitely on the bland side. Any presence of the cardboard (E)-2-noneal was probably covered up by the sour apple, something I attribute to an abundance of alcedyhyde rather than fruit esters.

Without a doubt, the diacetyl qualities are in full effect, making this the slippy-est beer I’ve ever drank with a huge toffee presence. Given the sour element in conjunction with the diacetyl, it’s possible that pediococcus bacteria played a role, but that probably isn’t the case. Apart from the burnt bread element, possibly associated with the yeast crust at the bottom of the bottle, this is a textbook example of aged flavors taken to the extreme.

Wrap-It-Up

While you might not be able to get an 18-year-old Barleywine, I think this exercise demonstrates the appeal of leaving beer to the ravages of time. The general rules are just that, general ideas of what will happen. Due to the variety of malts, the kilning process and many other factors, every beer has a unique chemical composition, which means that no beer will age the same. It’s for that very reason that aging beer is such a fascinating and rewarding hobby and one that you can never start soon enough.

If you want to get into aging beer, know this: it’s 10% acquisition, 20% storage, and 70% patience. Buying multiples and opening one a year can make the waiting easier, but not everyone has the access or finances to hoard beers. Even if you just buy a local stout, put it away in a cupboard and forget about it. You’ll be surprised just how quickly it can turn into something great.