What To Do if Your Kettle Sour Beer Isn’t Souring

One of the most popular beer styles of the past decade is sour beer. Traditional Belgian Lambics and other classic sours take months, if not years, to make. Kettle souring is a much quicker process that leads to similar results, but what do you do if your kettle sour beer isn’t souring?

If your kettle sour beer isn’t souring, you must check that you used the correct ingredients. Once you’ve checked to be sure you used the proper yeast, wort, and other components, you want to ensure your brewing conditions are suitable and there aren’t any outside contaminants. 

In this article, I will look at what ingredients you may have forgotten or misused, what conditions may have been less ideal for souring your beer, and other potential problems that resulted in your kettle sour beer not souring, and what you should do differently. 

How Do You Know if Your Kettle Sour Beer Isn’t Souring?

One of the telltale signs that you kettle sour beer isn’t souring is if it doesn’t taste sour. But a more objective way to measure this is to test the PH. 

While it is often important not to let your PH get too low, in the case of sour beers, you are actually going for a lower PH than usual. So if you taste your beer and something isn’t quite right or see the wrong PH, you’ll know that you need to do some things differently. Let’s take a look.

Check Your Ingredients If Your Kettle Sour Beer Isn’t Souring

Sour beers are an enjoyable treat that can be lite, dark, or somewhere in between, but above all else, a sour beer needs to be sour! So, if I’m brewing a kettle sour and it isn’t souring, I need to ask myself why. The first thing I do is check the ingredients I’m using and ensure everything seems ok.  

Ingredients You Should Check if Your Kettle Sour Isn’t Souring

Check your ingredients and be sure that nothing has spoiled or was chosen incorrectly if your kettle sour beer isn’t souring. Some of these ingredients include:

  • Lactobacillus. Lactobacillus is one of the essential ingredients when souring a kettle beer; the bacteria is what produces lactic acid after the bacteria eats the sugars. If your lactobacillus is a weak strain or has been compromised, it may not correctly sour your beer. So choose a different lactobacillus and try again. 
  • Sugar. If you don’t add enough sugar to your beer, the lactobacillus won’t have enough to eat in the fermentation process. As a result, it will produce less lactic acid, and your beer will not be quite as sour as you like it to be. Try adding more sugar.
  • Malts. One thing you might want to check if your kettle sour isn’t souring is your malts. Acidulated malt is one of the most common malts people use when brewing kettle sours because you increase the chances of sourness using a malt with higher acidity. So when I’m not getting the sour results I want from my beer, I turn to the malt with higher acid. 

Best Ingredients for Kettle Sour Beers

Here is a quick look at what I consider some common best ingredients for kettle sour beers:

Best MaltBest Sugar Best Lactobacillus 
Any higher PH MaltFine Table SugarLactobacillus Plantarum

I suggest using these ingredients if your kettle beer isn’t souring because they are common ingredients found in kettle sour beers. If you’ve been experimenting with more obscure ingredients, I recommend going back to the basics! Try using these and see if your kettle beer sours.

Other Reasons Your Kettle Sour Beer Isn’t Souring

Besides ingredients, there may be other common reasons your sour beer isn’t souring. The beer’s environment being brewed or stored can directly impact whether your kettle sour gets sour enough. Here are several things that may prevent your kettle sour beer from souring that you might want to change.

Time Is Still a Factor With Kettle Sour Beer

Even though kettle sours don’t take nearly as long as beers like Belgian lambics or other sours, they still take some time. One of the reasons I love brewing kettle sours is that they don’t take nearly the hours and effort of other sours and can save you a lot of money. 

It is another example of how brewing my beer can save me a lot of money while producing great results, like in this video:

But, if I taste the beer the same day I brewed it, it most likely hasn’t soured enough yet. Even kettle sours need a day or two for the lactobacillus to do its job and make the beer nice and tart. So, if your kettle sour beer isn’t souring, try giving it more time!

Too Much Oxygen Can Impact Your Kettle Sour Beer 

You must ensure that your beer isn’t overexposed to oxygen. If you don’t do this, all kinds of microbes could enter the beer, and it might give you off-flavors that take over. The off flavors might distract from the sour taste and make the beer undrinkable. 

Like when you’re sanitizing your equipment, avoiding getting unwanted growth in your beer from oxygen is essential.Many lactobacilli are anaerobic, so they thrive in conditions that don’t have oxygen. 

This factor is important to know because you will eliminate the chance of further bacterial growth and give your lactobacilli an environment they crave. So make sure you’re not allowing too much oxygen into your brewing environment if your kettle sour beer isn’t souring! 

Temperature Can Affect How Long Kettle Sour Beer Takes to Sour

Another reason your kettle sour beer isn’t souring could be the temperature at which you’re brewing it. If your temperature is too hot or too cold, it might not be the optimal temperature for the souring agents to survive. 

Ensure you’re brewing at optimal conditions if your kettle sour beer isn’t souring. Lactobacillus does best under a specific range of temperatures, so try adjusting the temperature if you suspect your microbes aren’t thriving. 

Always Consult an Expert if Your Kettle Beer Isn’t Souring

Brewing should be a community activity. Whenever I have a question, I reach out to people and ask! If you’re having an issue with your kettle beer not souring, don’t hesitate to consult some friends online or in person and find out what might be your problem. 

You can also brush up on some brewing basics! Do this when your kettle sour beer isn’t souring, and maybe you’ll figure out why in less time. 

Final Thoughts

When brewing a kettle sour, I want a quick fix for a beer style that can sometimes take much longer to brew. I enjoy the fact that I can produce similar results to centuries-old styles that are much more complex in a fraction of the time.

It is essential to understand, however, that there are still lots of things to pay attention to that will impact if your kettle beer sours. Ensure you have the right conditions and ingredients when brewing a kettle sour to achieve the right sourness.

About HomeBrewAdvice

Hello, my name is Simon. Together with a group of writers I write about brewing beer and making wine. We all share a passion for the great things in life, such as making stuff from scratch.

The business of HomeBrewAdvice is to bring you great information, stories and product reviews from brewing at home, and making wine


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