How to Pasteurize at Homebrew Scale

[biertourist]

When the "big guys" ferment batches with wild yeast (well lab-purchased lacto, pediococcus, and brett anyway) and then blend it with another batch that has only been fermented with saccharomyces, they first pasteurize the "bug" batch so that the bugs don't continue to work on the new added batch. -How should we do this on a homebrew scale?

Obviously UV pasteurization is out, and anything involving temps approaching 70C is probably going to boil off the ethanol, so we can't have that.

I've talked to my friend who's finishing his PHD in Food Sciences here in Ireland and he's recommending that I use the "Low Temperature, Long Time" pasteurization technique which involves heating the "bug" batch to 63C for 30 min.

I think this is a great idea as it should kill the bacteria and yeast in the bug batch without boiling off any of the precious ethanol, but I'd love to find out how everyone else is doing this.(Including the small craft brewers.) -Is this the technique that is used to blend at these breweries?

My friend isn't in a brewing sciences course, but a food sciences course, so I want to make sure that it's application does make sense here. (I'm really just looking for that warm and fuzzy feeling that comes from knowning that someone else is doing this and it works.)

Thanks,
Adam

[biertourist]

Can anyone even direct me in a direction where I might get more information?
(I'm thinking maybe Babblebelt)

Thanks,
Adam

[brewinhard]

I am not so sure how many breweries do actually pasteurize their wild brews. Why do you feel the need to pasteurize them? If you are worried about packaging them, simply have separate hoses/tubing/autosiphon/kegs/bottling bucket for those brews. If you are trying to create a "stable" final product then your best bet is to achieve this through adjusting your mash temps to determine a low enough FG for your wort profile. This will limit the activity from the critters in the long run. But half of the fun of brewing wild beers is seeing how they change over time...and yes, the BBB could have some extra tips over there for ya! See ya there!

[biertourist]

I am not so sure how many breweries do actually pasteurize their wild brews. Why do you feel the need to pasteurize them? If you are worried about packaging them, simply have separate hoses/tubing/autosiphon/kegs/bottling bucket for those brews. If you are trying to create a "stable" final product then your best bet is to achieve this through adjusting your mash temps to determine a low enough FG for your wort profile. This will limit the activity from the critters in the long run. But half of the fun of brewing wild beers is seeing how they change over time...and yes, the BBB could have some extra tips over there for ya! See ya there!

If I'm looking to create a blended wild brew, as soon as I blend the "bugged" portion with the "unbugged" portion, the bugs will start fermenting the residual sugars from the bugged portion. -If I bottle, I'll end up with bottle bombs. Blending gives me the ability to control the funkiness and sweetness/sourness levels, but only if I can pasteurize.

-This is the method that Rodenbach Klassiek and many other's use, I'm just curious how to do it on a homebrew scale. (Wild Brews recommends many, many instances over and over where you should be pasteurizing beers at this point, but never talks about the available methods.)

So, yes, you could say its about creating a stable product, but I feel more like it's about gaining a degree of control over the process/bugs.

Someone at BBB will definitley know.


Adam

[andy77]

You could set up an actual pasteurization system. Set up two counter-flow chillers in line. Through the water lines run hot water through the first, and cold water through the second. Run your soured beer through the wort line with a flow-rate such that the beer entering the hot 'chiller' reaches 160-165F for 15-30 seconds, and then enters the second chiller and is immediately chilled back to room fermentation temps. Voila' evaporation free flash pasteurization.

From there, I suppose you could go straight to a keg for blending.

[Mylo]

If I'm looking to create a blended wild brew, as soon as I blend the "bugged" portion with the "unbugged" portion, the bugs will start fermenting the residual sugars from the bugged portion. -If I bottle, I'll end up with bottle bombs. Blending gives me the ability to control the funkiness and sweetness/sourness levels, but only if I can pasteurize.

This is exactly why most guezes (that contain blends from 1, 2, and 3 yr old "buggy" beer) are not very carbonated. Better to err on the side of less carbonation. Unless you're making Orval, excessive (or even normal) carbonation is not really necessary.


Mylo

[biertourist]

You could set up an actual pasteurization system. Set up two counter-flow chillers in line. Through the water lines run hot water through the first, and cold water through the second. Run your soured beer through the wort line with a flow-rate such that the beer entering the hot 'chiller' reaches 160-165F for 15-30 seconds, and then enters the second chiller and is immediately chilled back to room fermentation temps. Voila' evaporation free flash pasteurization.

From there, I suppose you could go straight to a keg for blending.

Wow, what a REALLY great idea! Throroughly impressed.


Adam

[brewinhard]

I still think your best bet is to mash the normal half batch at a lower temp so it will finish out more at a lower FG than the bug half. This will give you some control over the finished product. I have been doing sour beers for about 2.5 yrs now (quite frequently) and never had any of them really get over attenuated (even in the bottle over time). But like Mylo said, just account for some extra fermentation after packaging and lower your priming rate a tad. NOt a big deal. If you are kegging, then pasteurizing really does not have any need especially as once the beer is blended and chilled down the wild yeast/bacteria will pretty much come to a halt in terms of their growth and continued fermentation.