Pediococcus Beer Infection: What is It & How to Prevent It

Pediococcus beer infection is the worst because it is so common. It is the primary reason to keep your brewery highly sanitized as it can infect and spoil a batch of beer in a matter of weeks. But what is pediococcus? What does it do? And how can you prevent it?

What Is Pediococcus?

Pediococcus is lactic acid bacteria that is actually highly beneficial to the human microbiome. It is a probiotic that lends itself to excellent gut health in the human body, and gut health is the key to all health. Various strains of pediococcus are employed in the fermentation of meats and vegetables, creating the vinegary or souring effect.

Sadly, they do not do wonders for beer and wine. Instead, they wreak havoc.

How Does Pediococcus Get into Beer?

Pediococcus is a highly prevalent bacterium that can be found around virtually all food sources. It gets right to work feeding on sugars in vegetables, grains, and fruits, and turning them sour. This prevalence is why our ancestors were able to ferment foods for our health. Sauerkraut, kimchi, yogurt, and more have been brought to us by the amazing ability of pediococcus to attract to food and ferment it.

Thus, it is no wonder it gets into beer more often than any other wild yeast or bacteria.

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It is present in the environment, so any chance it gets to sneak into beer, it will. You might find it in cracks and scratches in equipment, lingering on un-sanitized spoons, stoppers, vials, measuring tools, or bottles.

Once it gets into your brew, it is impossible to get out. It will reproduce rapidly and infect your entire brew.

What Is a Pediococcus Beer Infection?

A pediococcus infection shows up in two ways – visually and through taste. Visually, it will appear as ropes or strands in the beer. Pediococcus is a rod-like bacteria, and once multiplied, those bacteria string together to form the strands you will see in beer.

At first, the beer might appear hazy, but over time the strands will grow bigger to form actual ropes in beer. It does the same thing in wine.

In terms of taste, you will taste a buttery flavor when you drink the beer that is off-putting. Interestingly, it does not turn beer to vinegar. Something about the interaction of this lactic acid bacteria, the grains, the hops, and the yeast, create a buttery or buttered popcorn effect instead.

Still, it clearly does not belong in beer.

It is important to note that pediococcus in beer will not harm you. In fact, it might do you some good. Sadly, the flavor is too intense for most people to enjoy it.

What to Do About a Pediococcus Beer Infection

Unfortunately, most of the time with a pediococcus infection in beer you must throw the whole batch out. Very few people want buttered popcorn beer.

At the same time, you might find that the infection in your beer is not entirely undesirable. In the case of only light buttery flavor, you might want to bottle or keg your beer and drink it immediately, before the flavor grows even stronger.

It is entirely up to you, and it may be worth at least sharing it with friends with open minds, so you don’t waste an entire batch.

How to Prevent a Pediococcus Beer Infection

To ensure you don’t run into this problem again, clean, clean, and clean some more.

The cleaner you keep your brewery, your equipment, and even your personal attire, the less likely you are to have an infection of any sort.

It would be much worse to have an infection that actually makes people vomit. No one wants that.

Thus, clean all of your equipment with a sodium percarbonate solution, throw out any equipment that has even the tiniest scratch or crack on it, and run your bottles and their caps through the dishwasher on the highest setting.

Follow these instructions, and you can all but guarantee that you leave the butter to the popcorn and out of your beer.


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