COMMON INFECTIONS COMMON INFECTIONS

Written and photographed by Destilador Enmascarado

Welcome to the first appearance of the Destilador Enmascarado (Masked Distiller) — an occasional column dedicated to sharing knowledge and solutions to common challenges within the distilling industry that are maybe just a bit too taboo to publicly attach your name to. Written under a pseudonym, but full of good info. We’ve all dealt with it. Now let’s talk about it!

Is there something we don’t talk about that we should? Email info@artisanspiritmag.com and let us know.

“Every one of you reading this page, look out! Because soon — VERY SOON — the most horrifying monster menace ever conceived will be oozing into this distillation. It crawls! It creeps! It eats your fermentation alive! From then on there’s no stopping it as it spreads from ferm to ferm. How can it be stopped?! Mob hysteria sweeps one city. Before long, the nation! And then the WORLD could fall victim to the blood-curdling threat of… THE INFECTION.”

— Parodied from the trailer for 1958's “The Blob”

It’s happened to the best of us, even if we’re loath to admit it.

If your quality assurance is up-to-snuff, you should catch it relatively quickly.

Perhaps it starts out a slightly savory meaty note on your new make. Or maybe you catch it even sooner than that, noticing that your pH in your fermentations have been dropping a bit too precipitously.

It may be something visual — a chalky, skin-like growth growing across the top of your fermentation. Or a slimy bit of beer or wine, hanging like so much mucus from your sample port.

No matter how you may have discovered it, the truth is it’s here. An infection. But the good news is if you follow proper remediation procedures, you can eradicate your infection and get your production back on track.

B u T, FI r ST — WHAT CA u S e S AN INF e CTION?

Infections occur when fermentation-spoiling bacteria or wild yeast make it into your fermentation and start competing with cultured yeast for the sugars you've worked so hard to create.

Distilleries (as well as breweries, vineyards, meaderies, kombucheries) are full of sugar. Full of proteins. Chock full of carbohydrates. Positively brimming with vitamins and minerals. It’s warm. It’s moist.

All of these things create an ideal habitat for bacteria to set up shop.

It’s often said that distilleries typically don't have to adhere to as strict sanitization regimens as wineries and breweries do. There are a couple of reasons for that. A little bit of wild yeast can add complexity to aged distilled spirits. Maybe a bit of funk (from the correct and desirable bacteria) gives your spirits that bit of complexity you’re looking for. Having quicker, higher ABV fermentation also means the opportunities for infections to take hold are reduced.

It's one of the big reasons open-top wooden fermentation is so common in distilling.

However, this does increase the chance of an infection taking hold.

WHY DID YO u G e T ON e ALL OF A S u DD e N?

As mentioned above, in general distilleries don't typically need to adhere to the same sanitization level as (most) beer and wine production areas.

What that does mean is that we're naturally exposing ourselves to higher chances of infection. And it also means that by the time it's showing up in your sensory, the infection has sunk its talons into the process and it's a nightmare to unhook it.

You may then ask yourself: Why have you been able to consistently produce infection-free new make (other than maybe a couple of hiccups) for the past few days/ months/years without major issues? After all, you’re following the same cleaning regimen day after day after day.

Infection can set in anywhere: The mash tun. The heat exchanger. Hoses. Fermenters. Even your tri-clamps and gaskets. Infection can thrive in the humid nooks and crannies of our floor and floor drains. Splashing from the floor up into the production space could even be the source.

Climbing into the mash tun to rinse out left-over grain could bring it in on your clothes or the bottom of your boots.

The biggest reasons are what we’ll call the double Bs — Biofilm and Beerstone.

Biofilm

The American Society of Microbiologists defines biofilm as an organic structure that acts as a microbial catch-all. Biofilms form when a group of microbes sense a given surface and adhere to it. Bacteria then set up and begin propagation. The film is further solidified in a polysaccharide (sugar) matrix.

This matrix forms a channeled structure, protecting the bacteria from external environmental factors, while simultaneously forming a trough that force-feeds nutrients and waste byproducts to the bacteria, allowing for ongoing colonization and maturation of the embedded bacteria. It also works to protect the bacteria from attempts at cleaning and sanitization.

In super simple terms — think of biofilms like the lamination on a piece of paper. The paper is the bacteria that has set itself within your production space, and the biofilm is the laminate protecting the paper from any attempts to properly clean it. Because the bacteria can hide in the biofilm, traditional cleaning methods aren’t particularly effective in eradicating them.

Even more troubling — Early biofilm buildup is often invisible to the naked eye until it has aggressively built up. Which leads us to beerstone, a type of biofilm.

Contaminants Biofilm Matrix

Beerstone

Beerstone is “calcium oxalate” (C2CaO4). The build up of beerstone is largely due to a reaction between alkaline cleaners (e.g. caustic), hard water minerals (calcium and magnesium), and protein in the form of amino acids (from your feedstock and yeast).

The organic compounds found in the wort and beer will combine with metals in the water — i.e. calcium and magnesium. This forms the oxalate. Bacteria can then find a home in the calcium oxalate, allowing the microorganisms to avoid any sort of interaction with your standard cleaning regimen. Use of caustic directly on the beerstone then exacerbates the issue, forming a cover by creating additional precipitate because the caustic agents react with the CO2 given off by the fermentation process.

You'll begin to notice this inside the fermenters and even inside the mash tun. The oxalate begins to build up over time, leaving an unsanitary surface that offers an environment that can harbor microorganisms.

Add in little nooks and crannies from the welds where infections can hide (and perhaps a huge shadow caused by the inside lip of a manway where a CIP process can’t reach), and that build up over time is like getting into the car and not buckling your seatbelt.

Sure, we may be able to go to and from our destinations without any major issues normally; but, the law of averages tells us it's eventually going to catch up with us.

Biofilm can build up over time. By the time it's visible, you have an even larger challenge on your hands. Some vessel designs also create "shadows" that your CIP system can't reach — such as this example from a beer fermenter where an inside lip prevented standard CIP processes from achieving full efficacy. These areas require special care during cleaning and ensuring sanitization — oftentimes requiring hand scrubbing and additional rinsing.

Beerstone can creep up suddenly, as biofilm buildup can initially be invisible to the naked eye. It takes time after time after time of failing to break down the biofilm layer before you can really see it. And by then, it’s a nightmare to remove.

Which it obviously can! Because here we are staring at sepia-toned stainless.