Sometimes beer doesn’t turn out as expected. There are a few ways to tell if your beer has gone bad at each step of the process. What can you do with bad beer? When is it beyond saving?
A bad batch of homebrew beer can be used for cooking, baking, or making your own garden fertilizer rather than dumping it out. To confirm that the beer has gone bad, be sure to actually taste or smell the beer and check for any visual signs of infection whether the beer is in the fermenter, bottled, or kegged.
Keep reading for signs your beer has gone bad and what you can do next.
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How to tell if your homebrew beer has gone bad
Things may seem a little off while you’re brewing or after you’ve bottled or kegged your batch, but don’t go throwing it all out just yet! There are a few signs your beer isn’t turning out quite right, ranging from visual clues to funky flavors.
Thankfully, since it’s highly unlikely bad beer can cause illness (more on that later), be sure to sample your batch before dumping it all down the drain.
In the fermenter
When your batch is fermenting normally, you’ll notice plenty of off-white foam that shows the yeast is doing its job converting sugar into alcohol. The krausen, or yeast cake on top, could also contain hop particles, which may make it look kind of funky but it’s perfectly fine. It’s the life of your beer!
Things have gone awry if there’s little to no foam (although you may just need to give it another day or so) or if you notice mold growing on the top. You’ll know your beer is infected if there’s a slick white sheen to the surface and it smells awful.
Signs bottled beer has gone bad include residue around the bottle top or if it smells musky when poured into a glass. That smell indicates your beer is skunked, which was likely caused by prolonged exposure to light.
Storing your beer in clear bottles, rather than brown ones, can exacerbate this issue.
If kept in the right conditions, a keg can remain fresh for a couple of months. Air and heat are enemies of beer. If the temperature fluctuates or if the keg is improperly sealed, you’ll end up with bad beer on your hands.
You’ll know the keg is bad if the beer has a foul smell, an overly cloudy appearance, or a flat or stale taste.
Three things to do with bad homebrew beer
Okay, so you’ve figured out what’s wrong with your beer.
You have a few options to give your bad beer a second chance that doesn’t include the kitchen sink.
Adjust the ingredients
If your yeast is underperforming or you accidentally underpitched your yeast, you’ll end up with a sweeter, lower-gravity beer. That’s because the yeast was unable to eat all of the sugar, thereby the beer wasn’t able to reach its full alcohol potential. Is this automatically ‘bad beer’?
But you still have time to experiment with this batch, either by repitching your yeast or adding hops of your choice to enhance aromas. Check here for a list of hop varieties and their tasting notes, and consider this an opportunity to experiment.
And if mold is growing on the top? Just skim it off with a (sanitized!) spoon. Siphon off some beer and give it a taste — you’ll be able to tell if it’s still worth saving because infected beer will be undrinkable.
Unfortunately, infected beer is only destined for the drain. Skunked, flat, or otherwise less-than-appetizing beer has other applications.
Cook with it
You can use skunked or flat beer to marinate meat or boil sausages. This way, you can take advantage of the flavors you’d developed before the beer went bad. In addition, the enzymes in beer help to tenderize the meat while adding all that flavor. Make sure to take into account just how skunked it is and adjust tastes accordingly.
You can also bake bread with beer you don’t want to drink. If your beer still has carbonation, it will act as the rising agent for the dough.
Flat beer, however, will require yeast or baking powder in order for the bread to rise.
Use it in your garden
You can make your own fertilizer using beer and other household items.
Beer has nutrients like potassium and phosphorus that can help your grass grow, and when mixed with substances that produce nitrogen and ammonia, together they make for a seriously happy yard! Additionally, the carbohydrates in beer feed microbes in the soil. These microbes stimulate plant life in turn.
Try it out on a small patch first before spraying it throughout your lawn. If nothing else, pesky slugs love beer. Set a small dish in a shallow hole in the ground and fill it with beer to attract and drown those plant-destroying slugs.
Can bad homebrew make you sick?
We’ve covered it here before, but the quick answer is no. Infected beer could make you sick to your stomach due to the smell and taste, but the alcohol content and low pH kill off germs that can make you ill.
So feel free to taste your beer to appraise before dumping it without fear of food poisoning.
How do I keep this from happening again?
Review your sanitation and storage practices. Remember that cleaning and sanitizing aren’t the same thing – cleaning removes dirt and germs from surfaces while sanitizing kills pathogens. Some equipment may need to be replaced, like scratched-up plastic pieces that can harbor germs.
Keep your beer in a dry, cool place in brown bottles rather than clear ones, and be sure to drink your beer within its shelf-life. Check the seal on your keg and remember that heat and air will quickly ruin your beer.
It’s disappointing when a batch doesn’t turn out as expected, but in almost every case you’ll be able to give that beer another life, whether it’s with patience, mixology, or thinking outside the box. Even infected beer, while undrinkable, provides a learning opportunity.
So don’t fret over a beer that is imperfect – you’ll know better for next time, and might get a loaf of delicious bread or a pest-free garden out of it in the meantime.