Lambic. And yes, I’m calling it that. Part 4 – Recipe and Brewday

In part 1 of this series, I covered what lambic is. In part 2 I covered how to recreate lambic processes more easily, at least on a homebrew scale. In part 3 I covered a variety of questions and ideas that I wasn’t able to cover in the first two parts.

Today, in part 4, I’ll cover my recipe and brewday.

Recipe Creation

A basic lambic grist is comprised somewhere between 50/50 and 70/30 pilsner/wheat. I went with a roughly 65/35 split. I used Pilsner malt and Wheat malt from the folks over at Riverbend Malthouse in Asheville, NC. If you’re ever in that area, give them a call and see if they’ll give you a tour. It’s a fantastic experience. My experience with the pilsner malt has been that it has a great earthy flavor, but is a little prone to tannin extraction if the pH isn’t just right. So lambic that might benefit from some tannin seemed like a great way to use it. The wheat malt has been fantastic in all the beers I’ve used it in and it’s what I had on hand.

Mashing with Wheat Flour

I found a scholarly article that indicated that up to 25% of the mash could be wheat flour with no ill effects. So with that in mind, I decided to mash 8oz of wheat flour in the main mash and add about 8 oz in the sparge to get the starch I want. I was using a brew bag in my cooler so I wasn’t worried about lautering. I use a comically large whisk to stir my mash so I wasn’t really worried about dough balls either. So I just added the first 8oz of flour in with the rest of the grain. This worked pretty well.




I decided to mash at a high temp (161F) instead of adding carapils malt. I’m still not sure which would be better. Perhaps giving the Saccharomyces strains more simple sugar to easily ferment would be better than giving them some assumedly more complex sugars from a higher mash temp. I may try carapils for another iteration of this in future years. For this one I just decided to keep things simple.

You may notice some small white flour balls in the second picture. These were a result of just dumping the flour into the strike water. They eventually were well integrated. That giant whisk I mentioned earlier definitely helped. It makes stirring the mash and integrating the grain with the strike water very quick and easy.

I was able to sparge at the extra hot temp of 178F, which is great for lambic. Should be plenty of tannins for the bugs to do interesting things with.


Lautering was fairly normal, but I had some issue with the brew bag getting stuck to the outlet. Eventually I just lifted the bag slightly with a rope and an eye bolt and it ran off fine.


I decided against melanoidin malt in the interest of simplicity. I was brewing this on a weeknight which meant it needed to be a relatively quick brew, but I was able to get my water heated a little faster than normal by using my boil kettle temp controller to pre-heat the water. I ended up boiling for a little over 2 hours, which is fine, since Cantillon reportedly boils for 2 hours. I collected 14 gallons and flamed out with a touch over 11.


This was definitely the fun part. I had never coolshipped a beer before, but i read a lot about it on the Milk The Funk Wiki and the Milk The Funk Facebook group. Consensus seemed to be that trying to scale down a commercial coolship was a bad idea because it didn’t provide the correct cooling rate and it didn’t have the correct surface area to volume ratio. Apparently a standard boil kettle was a closer approximation, and some insulation could be used to slow the cooling rate to appropriate levels. The target coolship dimension, regardless of volume is that the wort should be approximately 1.5 feet deep.


I used a bottom draining keggle for my coolship and wrapped it in 3 layers of Reflectix insulation. My wort depth was not ideal as it was probably a little over the 1.5 foot mark, but this was the best I could do. I used a couple pieces of scrap wood to hold the lid over the top of the keggle to keep any large debris from falling in, but still allow the wind to blow through and bring any microbes with it that it could. The coolships used in Belgian Lambic breweries are in large rooms with louvered windows, so these openings seemed appropriate to me.

I sat my keggle up on some bricks on the stairs at the back of my house so I could run off via gravity into my fermenters. I cut a circular piece of reflectix to go under there and also stuffed a towel under it to keep the wind from blowing through and cooling the beer too quickly. Coolshipping is reported to work best when the nighttime temperatures are very cold, so I picked a night (2/10/16) that had a low of 21F. I thought I recalled hearing Jean Van Roy recommend that the daytime high should be below 45F, but the MtF wiki indicates it would be a maximum nighttime low of 45F for coolshipping. Either way, the day I picked fit the bill.

The only mistake I think I made was I over insulated the coolship. The beer entered the coolship at 11PM and had only reached 79F at 11AM the next morning when the sun had already come up and began to warm the environment up beyond temperatures I was comfortable with. I think that lambic brewers target 8-12 hour cooling times. In the future, I would use maybe 2 layers of reflectix and possibly not protect the bottom of the coolship so much, especially if the night were warmer. Getting the beer into the coolship earlier in the evening might help too.



I decided against hazarding a ferment in the whiskey barrel I have kicking around. I think the risk of getting too much oak and whiskey flavor is too great to chance it. I’m just going to ferment in the old standby Better Bottles. I didn’t bother sanitizing them. Just cleaned with PBW and rinsed well. Afterall, beer that was exposed to the great outdoors was about to go into them. I’m using S airlocks and plasticoid bungs because S airlocks are less likely to go dry and plasticoid bungs have the lowest oxygen permeability of the common and cheap closures for carboys.

The next evening after coolshipping, I drank a bottle of Drie Fonteinen Geuze, my favorite, and added the dregs to one of the carboys. The other one will stay purely spontaneous.

Interestingly both carboys started fermenting right around the same time Saturday morning. If anything the 100% spontaneous carboy may have started first and has had a slightly more vigorous fermentation the entire time. Both carboys are still fermenting away as of Monday night 2/15/16. Fermentation is occurring around 68F.

Well, that’s going to be it for the lambic series for quite some time. I might be able to taste this one in 6 months or so. I’ve got warning stickers on it not to taste it for at least 2 months to be sure that any nasty enteric bacteria have died.

Here’s the recipe! Cheers!

Lambic, Deal With It.

Recipe Details

Batch Size Boil Time IBU SRM Est. OG Est. FG ABV
11 gal 120 min 8.7 4.03 1.057 1.003 7.09

Style Details

Name Cat. OG Range FG Range IBU SRM Carb ABV
Lambic 23 D 1.04 - 1.054 1.001 - 1.01 0 - 10 3 - 7 0 - 0 5 - 6.5 %


Name Amount %
Riverbend Pilsner 17 lbs 65.38
Riverbend Appalachian Wheat 8 lbs 30.77
Wheat flour 1 lbs 3.85


Name Amount Time Use Form Alpha %
Lambic Blend 4 oz 60 min Boil Pellet 1.2


Name Lab Attenuation Temperature
- - Default 95% 66°F - 72°F
Spontaneous Fermentation 0% 32°F - 32°F

3 thoughts on “Lambic. And yes, I’m calling it that. Part 4 – Recipe and Brewday

    • I just brewed my year two and took some tasting notes on year one. I’m super behind on posts, but I hope to write one about year two and tasting year one soon. Thanks for the feedback!

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