The Keys to Getting Great Results with Kettle Sours

Follow these tips and techniques to take your quick sour beers up a notch.

Jamie Bogner Dec 30, 2016 - 4 min read

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While sour beer “purists” might scoff at the idea of making great sours with quick souring methods (we’re looking at you, James Howat of Black Project and your “Death to Kettle Sours” T-shirt), others have found creative ways to get award-winning results that don’t take years to produce. But doing so requires a bit of effort (nothing is easy, is it?) and the right gear. Follow these tips and techniques to take your quick sour beers up a notch:

1. Boil before you pitch.

It is possible to go straight from mash out into a vessel for Lactobacillus souring, but award-winning professionals such as Funkwerks’ Gordon Schuck always boil after the mash and before they sour in order to kill off any latent Lacto that might have come from the grains themselves and to lock in their fermentable sugars. You don’t need to boil long—10 minutes or so—but Lacto souring with a pure culture that you pitch typically produces better results than souring with your pitch plus whatever was living on the grains.

2. Get rid of oxygen before pitching Lactobacillus.

While this is easier for commercial brewers who can seal and purge their kettles with less effort, there are a few methods homebrewers can use to achieve the same results. On the cheap and easy side, some brewers purge with CO2 and place plastic wrap over the top of their kettle once they’ve pitched to prevent ingress of additional oxygen. If you have a lid for your kettle, that can work, but consider a silicone ring for it that can provide a more airtight seal. If you’re handy and plan to kettle sour frequently, it may make sense to drill out your kettle and place a carbonation stone in the kettle to push a continuous blanket of CO2.

Yet another method is to load your wort into a non-kettle external vessel for souring—after your mash, run off your wort into your kettle, and while you’re giving it a quick 10-minute boil to kill off any latent Lactobacillus, clean out your mash tun then chill to your Lacto pitch temperature and move the wort into a mash tun or fermentor with a temperature controller that provides for heating, such as the Brewjacket Immersion Pro, the Ss Brewtech Infussion mash tun with heating element, the Ss Brewtech Chronical fermentor with temperature control coils, or even the 40W heating element from Cool Zone wrapped around a glass carboy.


If you brew with gas, these are your best solutions for maintaining consistent temperature as you sour, as you don’t want to leave a gas burner on for 24 hours or more. If you brew on an electric system, you have more options for keeping consistent temperature in the kettle itself.

3. Find the right temperature for your Lactobacillus.

120°F (49°C) seems to be the standard temperature for kettle souring with Lactobacillus, but pro brewers we’ve talked to each have their own magic temperature, from 90°F (32°C) up to 120°F (49°C), that provides the best mix of flavor and speed for their quick sour beer. Some folks swear by the lower and slower 100°F (38°C) temperature while others find that 120°F (49°C) gets it down to their target acidity faster with less time for off-flavors to develop. Experiment in that temperature range with the culture you use, and find the temperature that fits your taste.

For more information about the kettle souring process, best practices, and successful results, see Craft Beer & Brewing Magazine®’s online class featuring Funkwerks’ Gordon Shuck.


Jamie Bogner is the Cofounder and Editorial Director of Craft Beer & Brewing Magazine®. Email him at [email protected].