The Not So Mysterious Case of the Stale Beer

Update 3/24/16 - We've had some retailers and distributors contact us about this. The good news is almost all of this beer is gone now. There are some pockets in the suburbs that might have some left, we're looking into it. Also, NOT ALL CANS have staled. Why? Not sure. We think it might be based on how long the beer was kept cold, but not certain. These are the challenges that a brewery faces when it starts bottling or canning. We're getting it all figured out. 

Additionally, as of yesterday, all 4-packs will have a grocery story type sticker on top with the packaging date. The newest batch of cans of Entrenched won't have the stickers as we didn't have the pricing gun yet, but yesterday we were able to sticker the first batch of Phobophobia cans. Can't do individual cans yet as date printers cost $$$, but this will work for now. Also, the newest canned batch of Entrenched is awesome. No issues at all. We got this now.

Let's discuss that first canned batch of Entrenched, shall we?

First, real quick: the first batch was undercarbonated. Dumb mistake, easily solved. New batch of cans is dead on with carbonation. The new batch of cans is also dead on with not doing this....

I wanted to get all the data first from laboratory analysis, but until then, I wanted to address this stupid, stupid mistake so you people don't think we're just all hype and no beer. Don't let your eyes glaze over. There is a point here.

We brewed the first canned batch of Entrenched over a period of 2 days. 20 bbl on day one. 20 bbl on day two. We canned it on Feb. 12. Both batches went into the same fermenter (we have 40 bbl fermenters). This is a common way of brewing depending on a brewery's schedule and the amount of yeast cells available to pitch into the fermenter. 

During the process of boiling wort (unfermented beer), most of the oxygen in the wort goes out of solution and into the air. The problem is yeast cells need oxygen during the first part of their fermentation phase. Yeast absorb the oxygen and use it to create healthy cell membranes by creating sterols. Biochemist words, not mine. So you have to get some oxygen back into the wort. for this to happen. BUT ONLY DURING THE FIRST 24 HOURS AFTER YEAST HAS COME IN CONTACT WITH WORT*. We'll come back to that in a sec. It's a biggie.

When you brew, you have to induce oxygen into the wort (unfermented beer) on its way to the fermenter from the boil kettle. We do this with a stainless "stone". It has very tiny holes, we run pure oxygen through it, the cooled wort passes by the tiny bubbling oxygen, the oxygen dissolves into the wort, and the wort proceeds to the awaiting fermenter.

The yeast now absorbs this oxygen during the first 24 hours or so, as mentioned earlier. This is called the "lag phase". After the oxygen is absorbed (and other compounds like nitrogen), the yeast cells create healthy cell walls and then proceed with the rest of their fermentation stages.

We had never brewed two consecutive days in a row into the same fermenter. So we were out of our normal process, and that's when problems seem to happen for us.

We fully understood the fermentation cycle of yeast. When the time came on the second day of brewing, we said to ourselves, "Should we aerate the wort this time?". We went back and forth and then somehow, someway, we rationalized that we should.

Dumb, dumb mistake.

The left is good. The right is bad. In more ways than one.

The left is good. The right is bad. In more ways than one.

See that photo? The left is fresh Entrenched. The right? Well that was poured from the first batch of cans about two days ago. Brown. The foam is almost gray. 

That is called staling. Hyper-staling. We managed to accelerate the aging/staling of our beer by MONTHS when we added oxygen on that second day.

Beer and oxygen do not mix. There are a few exceptions to this rule including barrel aging , but only in certain circumstances. The ONLY time oxygen should be present in the standard brewing process is during that first 24 hours, so the yeast can pull all that oxygen in. After that, no more oxygen. Ever.

When beer is packaged in kegs/cans/bottles, breweries go to great lengths to purge oxygen out of the container with CO2. When we transfer from a fermenter to the brite tank, we purge the brite with CO2 and then use pressurized CO2 to push the beer over. No oxygen. Ever.

When we introduced that oxygen on day two, it stayed in the wort. It combined with various compounds in the wort and formed staling compounds. Normally this would take months in properly packaged beer sitting on a shelf. In our case it took about two weeks.

When beer stales/oxidizes lots of stuff happens and all of it bad. First, for beers with lots of hop flavor and aroma, it all goes away. No hop flavor, no aroma. And the beer turns color. And the beer can taste like cardboard, but not always. It can taste caramelized, iced tea-like, and well, just bad. Real bad.

We are going to have the old and new cans of Entrenched analyzed by a large, local brewery with the facilities to do this. Once we have some data, I'll post an update. 

Until then, here's the deal. If you bought those cans, and your beer looked like that, send me a message on the contact page and we'll arrange to get fresh, non-oxidized beer to you. If you come by the brewery, we'll throw in a free tour. 

We apologize greatly for this stupid, stupid mistake. It will never happen again, trust me. That photo will be framed and mounted on the brewery wall as a warning to all employees about the importance of keeping oxygen out of beer. Also, the importance of not being stupid. 

*For high gravity beers like barley wine, imperial stout, etc, it can be beneficial to aerate the wort with oxygen on the second day of fermentation, due to the stressful environment the yeast is under.  But never for normal gravity beers, like Entrenched.