Thursday, September 5, 2013

Sour Mash Wit

There are many ways to add sourness to the finished beer.  Simply adding lactic acid, long fermentation with wild yeast and bacteria, acidulated malt and the only method I have yet explored till now the sour mash.
I have used straight lactic acid to add sourness to a Berliner Weiss that didn't get as sour as I had hoped with the bacteria alone.  While this worked and was very easy, it lead to a sourness that was one dimensional and somewhat flat.

I have also conducted long fermentation's (2+ years) with a mixed culture of sacc, brett and bacteria to add sourness to the beer.  While these beers had the most complex sourness and aroma it was time consuming and also a gamble.  You never know when the correct level of sourness with be were you want it or if it will ever get there.  It also is a very good possibility that it could get too sour for your liking using this method because you have so little control.

The final method I used for today's batch of Sour Wit is to conduct a sour mash. Lactobacillus bacteria are naturally found on grain husks so it is fairly easy to culture that up to use in your mash.  The benefits of a sour mash is much greater control of the final acidity.  As soon as you are happy with the level of acidity you increase the temperature to kill the bacteria.  Another benefit by killing the bacteria you don't have to worry about the acidity increasing with time or the fear of infecting future beers.

I made a 2000ml starter with no hops and boiled for 10 minutes.

Chilled to 110F

Add 1 cup of crushed grain and keep at 100F-120F.  I used the plate I use for making yogurt.

I let it go 48hours till all the grain dropped to the bottom and it had a distinct sour milk smell

I then mashed my grains for my beer like normal, quickly brought it up to a boil and then chilled it down to 110F.  I then added the majority of the bacteria rich liquid from my starter to my mash and let it sit for 14 hours at 110F till the mash had a white pellicle confirming it is lactobacillus doing its thing. Another benefit of brewing with electricity is the ability to set the temp to whatever I need and walk away knowing it will hold that temp for as long as needed.

I then boiled the wort and hopped as normal.  The boil was stinky boiling off all of that spoiled milk smell.  But the final wort smelled normal and tasted very tart.  Very excited to try this one out, if it works well it will allow me to quickly sour beers with a high level of control.

Sour Wit

Recipe Specifics
Batch Size (Gal): 5.50
Total Grain (Lbs): 9.5lbs
Anticipated OG: 1.041
Anticipated SRM: 3.3
Anticipated IBU: 11.9
Brewhouse Efficiency: 70 %
Wort Boil Time: 60 minutes

47% - 4.5 lbs Pale Malt
47% - 4.5 lbs Wheat Malt
6% - 8 oz Flaked Barley

.75 oz Ahtanum ( 4.5AA ) Boiled for 60 min

14 hr sour mash held at 110F inoculated with a lacto start from grain husks

WLP400 Belgian Wit
Homemade Lacto Starter

Mash Schedule
Sacch Rest 60 min @ 148

Mash Out 10 mins @ 168

Sour Mash 14 hrs @ 110F

9-4-13 - Wort tasted sour but very clean.  Boiled and hopped as normal.  Pitched with WLP400 directly from the tube.

9-7-13 - Fermenting nicely


  1. I can't wait to hear how this turns out. Been looking into sour mashing, but haven't gotten there yet. Send me a bottle!

    1. I will certainly send you a bottle once ready. I was impressed with the level of acidity I got and how clean it tasted, the smell on the other hand....