If you’re looking for the best brews for your beer money, where you shop could have as much impact as what you’re shopping for. This point was made for me a couple of weeks ago when I bought some bad beer at the supermarket. Not surprising perhaps, but I’d done the necessary due diligence. The beer was from a major brand, Stone Brewing’s Go To session IPA, and the date code said it was fresh (really fresh actually, canned just three weeks prior.) But when I got the six pack home and cracked a fresh can I quickly saw that something was amiss, and the beer’s aroma confirmed it. The Go To was cooked.

It’s been hot in Southern California, and I’ve been drinking more session IPAs than usual. I really love the high levels of hop character, the dry finish and the low ABV of this trendy style, and while Firestone Easy Jack or Pizza Port Ponto are usually my ahem, go-tos, I’d just finished a six pack of Stone’s Go To that was some of the best SIPA I’d ever had. Just two weeks old when I bought it from Cap N Cork in Los Feliz, the beer was eye-opening. Tons of tropical fruit and citrus flavors on top of a lean body with a bitter finish. It was a beautiful beer too, the palest gold color and brilliantly clear. So fresh. So refreshing. The six bottles did not last long, and I resolved to start buying more Go To — especially if I saw it fresh.

You can imagine my surprise a few weeks later when I poured the fresh can of Go To, and what I got was a hazy, almost murky, glass of beer that smelled distinctly of marmalade and cardboard. It wasn’t vibrant and bright — in flavor or appearance, and each can in the six pack was the same cloudy, oxidized mess. I suspected that some time during these cans’ short life they were exposed to high temperatures for a prolonged period. The heating had forcefully oxidized the beer and caused haze-forming proteins to link together into long chains.

Perhaps I should have suspected something when the beer was on-sale at Pavilions for just $9, but I figured that at only a couple of weeks old, I’d be safe. I was wrong, and I was pretty irked about it. This was the second time in recent memory I’d been burned by buying fresh beer at a supermarket that turned out to be mishandled and flawed in flavor. (I’d purchased a mixed 12-pack of Firestone Walker beers at Ralphs for a 4th of July party — the beer was all bottled between June 10th and June 14th, yet the lighter styles in the box also tasted oxidized and cooked.) I started formulating an editorial on the pitfalls of craft beer shopping at major retailers, and I stopped by a local bottle shop to buy another bottle of Go To so that I could show off the haze in the affected bottles with a side-by-side photo.

Unfortunately, in the darkness of the beer aisle at Vendome Liquors in Toluca Lake, I misread the date code printed on the bottle’s neck. What I thought said “Bottled: 06/06/16” actually read “05/06/16” (or maybe “05/08/16” — why are these so hard to read?). Nevertheless, I know that Vendome cold-stores their inventory, so I figured it’d be okay for the photograph. Well, I was surprised again when I poured that beer: it was much darker than the canned Go To (canned on 6/15/16 for reference). Flavor-wise, it was clearly past its prime and fairly oxidized but still much more palatable than the cooked can. But the color difference was striking, and I made some calls to Stone Brewing’s Quality Assurance team to ask about what would cause it.

“A textbook example of forced oxidation in the bottle,” was the answer from Rick Blankemeier — Stone’s QA Manager. Blankemeier has been with Stone for over six years, and after he moved over from the production side of the brewery he’s helped to grow the QA team from 2 people to 10. The top-ten craft brewery now operates 3 breweries on 2 continents, and their Quality Assurance programs are detailed and thorough, including multiple sensory panels per day, an assortment of lab tests performed at multiple points on every packaging run, and extensive long-term studies.

Blankemeier explains that If a beer is subjected to repeated heating and cooling cycles, from fridge temperatures to over 80 degrees fahrenheit, more haze will form in the beer. Oxygen found in the headspace of a package is forced into the beer as it warms and expands, and this forced oxygenation has all manner of detrimental effects on the appearance, aroma and flavor of a packaged beer. One effect produces the tell-tale wet newspaper or cardboard flavors found in oxidized beer through the transformation of fatty acids in the beer (from malt or yeast) into (E)-2-nonenal (aka trans-2-nonenal for the Cicerones out there). This compound is responsible for the well documented darkening of oxidized beer (which can increase the SRM of a stale beer by several points). Blankemeier points out that in the case of Go To, which is specified by the brewers at between 4 – 8 SRM, even a slight darkening is very noticeable.

Of course oxidation is also detrimental to the volatile compounds that make up hoppy flavors and aromas — compounds maximized in Go To through the “hop bursting” technique used by Stone. This all adds up to a delicate beer with relatively low shelf stability.

To recap, the early May bottle of Go To was darkened by oxidation from the time spent in the bottle, and while oxidative flavors were present, the beer was still drinkable — just a touch stale. The can from mid-June, on the other hand, was a cooked mess — hazy, off in flavor and with little hop aroma left. It had clearly been left in a hot warehouse before the supermarket chain stocked it in the cooler and slapped a big SALE! sign on it. But there’s one other little twist to the story that Blankemeier revealed: as some commenters on Instagram and Facebook had suggested when I posted the comparison photo, Stone had changed the Go To recipe in early May. The bottle in the photo was the old version, while the can and that initial stunningly delicious six pack that started this whole investigation was the newly tweaked recipe.

It was right there on the packages if I’d bothered to look closely: the old Go To was 4.5% ABV, while the new formulation was bumped up to 4.8%. Blankemeier insists that this has nothing to do with the color difference between the two samples, but why the recipe change? The suggestion came from Greg Koch who’d heard complaints that Go To was a little too thin and watery. He recommended bumping the ABV up slightly with a dextrinous malt to slightly increased the perceived body, and so more carapils was added to the Go To malt bill. As much as I enjoyed the original Go To recipe, and as little as I mind a very light body in my session IPAs, I have to agree with Stone on this call. The extra body gives the beer more presence on the palate and seems to make the hop flavor “pop” a little more.

The point of all this is simply cavet emptor — buyer beware. It’s not enough to buy local, fresh beer — you need to understand the pitfalls of the craft beer supply chain and buy from trusted sources. Even beer that’s just a few weeks old can have noticeable flavor degradation because of mishandling. Rick Blankemeier performs many tests, controlled aging, and shelf life studies, and he says flavor degradation happens relatively quickly: “from my experience, it would be about a week at room temperature. Hot temperatures will increase the rate of flavor deterioration exponentially.” Hop flavors are the first to go of course, so if you’re into the hop bombs, proper cold storage is even more important.

I’ve often quipped that friends don’t let friends by beer at BevMo!, as their mishandling and warm storage is infamous, but the more important point is why are we shopping for local, independent craft beer at major chains anyway? With vanishingly few exceptions, big chain markets don’t care about the beer they’re selling, they just care about the sales of the beer. I encourage you to seek out and support your local craft-focused retailer who treats their inventory with the respect that you do (i.e. keeps as much inventory cold as possible).