Low Enzymatic/Cold Mash/Low alcohol beer

[beersk]

I just started steeping a small test batch in my fridge. Will mash and pitch it tomorrow. Will report back.

@beersk How did you batch come out?

Not sure if folks are aware, but there is a really good thread on brewing sub 1030 beers here: https://www.homebrewtalk.com/forum/threads/sub-1-030-beers.378450/

Brewing it was good. Mashed in with 40F water and mashed for 13 hours in my fermentation fridge set to 38F. Checking the temp after mashing in and the next morning, it pretty much stayed right at about 45F. I didn't seem to get as much liquid out of the mash as normal and the resulting wort was super turbid. I held it at 150-155F for 30 minutes then brought up to a boil. The wort was really nice and clear at that point. I had to make sure to stir the bottom of the kettle as it was heating up as there seemed to be stuff wanting to stick to the bottom and would burn if I didn't make sure to keep it stirred. There was a lot of crazy protein in the boil that looked egg drop soupy. I've that before with low o2 brewing, this was similar, but the color of it was darker. I got about 25% efficiency over all and the wort tasted and smelled like normal with 1.020 OG. We'll see how it comes out in 2 or 3 weeks.

A lot of people will say this is a waste of grain, but I'd argue that it's really not. You're still getting out of the grain what you want, which is flavor, color, body and most important of all, beer. Alcohol doesn't have to be the end all be all of it. It's not a waste to me if I'm getting an enjoyable beer that is very low in alcohol.

 

[mwill07]

Brewing it was good. Mashed in with 40F water and mashed for 13 hours in my fermentation fridge set to 38F. Checking the temp after mashing in and the next morning, it pretty much stayed right at about 45F. I didn't seem to get as much liquid out of the mash as normal and the resulting wort was super turbid. I held it at 150-155F for 30 minutes then brought up to a boil. The wort was really nice and clear at that point. I had to make sure to stir the bottom of the kettle as it was heating up as there seemed to be stuff wanting to stick to the bottom and would burn if I didn't make sure to keep it stirred. There was a lot of crazy protein in the boil that looked egg drop soupy. I've that before with low o2 brewing, this was similar, but the color of it was darker. I got about 25% efficiency over all and the wort tasted and smelled like normal with 1.020 OG. We'll see how it comes out in 2 or 3 weeks.

A lot of people will say this is a waste of grain, but I'd argue that it's really not. You're still getting out of the grain what you want, which is flavor, color, body and most important of all, beer. Alcohol doesn't have to be the end all be all of it. It's not a waste to me if I'm getting an enjoyable beer that is very low in alcohol.

Looking forward to an update!

 

[bracconiere]

It's not a waste to me if I'm getting an enjoyable beer that is very low in alcohol.

YMMV

 

[kmarkstevens]

Grain is cheap and time is precious! Plus as any serious homebrewer knows, you need backyard chickens to eat the spent grains, turn it into fertilizer that is primo for the hops you grow for the beer you brew...it's the brewing cycle of life.

@beersk You ain't kidding about the egg drop soup. V1 yesterday I simply poured in all the cold steep water for ~4# grain. V2 today I cold steeped 5# grain, but tossed out the last 1-2 quarts of super trub. The trub truly looked like egg drop soup. v1 OG = 1010 (4# grain and 2.5 gallons total volume), v2 OG = 1020 (5# grain and 2.5 gallons total volume). Not sure why the OG is so different but certainly an extra pound of grain and corresponding smaller volume of water added up to such a big difference? Guessing that this is going to take a dozen tries to triangle in on a keeper method.

On top of that: You can do a 2nd running if you want and toss in 20% 6-row to make up for the lost enzymes. At least, that's my theory. Just did 3.5 gallon mash on the 5# of cold steeped grains today with 1# of 6-row, and the iodine test says it converted. Bringing to a boil right now and will toss in 2 ounces of tettnang for a 20 minute boil and targeting around BU/GU = .9. I'm sure will have to play with the second running and flaked whatever or additional crystal or some honey to make it worth while.

 

[jtrux]

To get a low ABV beer, what about brewing like normal, once fermentation is over cold crash then transfer clear wort back to kettle and boil the alcohol out of it. Once cooled, add back a small amount of leftover yeast from fermenter and priming sugar. Never done this, just thinking out loud

 

[shoreman]

To get a low ABV beer, what about brewing like normal, once fermentation is over cold crash then transfer clear wort back to kettle and boil the alcohol out of it. Once cooled, add back a small amount of leftover yeast from fermenter and priming sugar. Never done this, just thinking out loud

That's a possibility, but boiling a liquid with yeast and hops post-fermentation is going to result in some pretty terrible beer. That was how alot of the traditional NA beers were created, but there's now other more flavorful ways to get to the end result.

 

[shoreman]

I posted this in the general, but has anyone here used Wheat or Rye Middlings? Might be another tool in the toolkit along with cold extraction:

https://www.experimentalbrew.com/podcast/brew-files-episode-66-middling-beer

basically you get all the flavor but only about 20-30% of the fermentables.

I can't seem to find a source for them at all online.

 

[beersk]

I posted this in the general, but has anyone here used Wheat or Rye Middlings? Might be another tool in the toolkit along with cold extraction:

https://www.experimentalbrew.com/podcast/brew-files-episode-66-middling-beer

basically you get all the flavor but only about 20-30% of the fermentables.

I can't seem to find a source for them at all online.

Can't find them around and what I do find is crazy expensive.

 

[kmarkstevens]

My samples tonight were not good. The v1 sample, did a mash hop on this one, was nasty. A weird burnt hop flavor (used EKG), burnt grass flavor. Ugh

Worse still, the v2 sample, which I did the full mash and then a proper boil with tettnang hops, also had the burnt grass flavor although not as strong as v1. The aroma was more than off putting.

Both were in the same bathroom that was ~69F during the day, and dropped at night along with the ambient temp.

Any trouble shooting thoughts? I dumped v1, and highly doubt v2 will age into something tolerable.

 

[BrewnWKopperKat]

Any trouble shooting thoughts?

Burnt grass flavors would suggest you burnt something.

Both were in the same bathroom

If you provide a complete recipe and process for each batch (two separate posts please), I may have time to take a look. If you are doing cold extraction (briess) please try to use their terminology.

 

[seatazzz]

I'm intrigued by this as well. I'd like to brew a really low ABV blonde for my dad; a former alcoholic and alzheimer's patient, he really loves the taste of beer and misses it.

Thinking of the hops; wouldn't it work if you created a hop "tea" and added it late in the short boil, to possibly avoid the grassy/burnt/icky hop flavor? Something clean like Cascade or maybe some Chinook to give it some zing. I might be trying this on my next grain purchase.

 

[BrewnWKopperKat]

I'm intrigued by this as well. I'd like to brew a really low ABV blonde for my dad; a former alcoholic and alzheimer's patient, he really loves the taste of beer and misses it.

Cold extraction may not be the right process for brewing a traditional tasting low ABV beer. From slide 2 of the PNWHC17 presentation:

Why do this?

... new malt flavors!!

 

[BrewnWKopperKat]

The v1 sample, did a mash hop on this one, was nasty. A weird burnt hop flavor (used EKG), burnt grass flavor.

Thinking of the hops; wouldn't it work if you created a hop "tea" and added it late in the short boil, to possibly avoid the grassy/burnt/icky hop flavor? Something clean like Cascade or maybe some Chinook to give it some zing. I might be trying this on my next grain purchase.

EKG is often considered to be a "clean" bittering hops.

FWIW, I've used EKG a couple of times with cold extraction batches and didn't get grassy/burnt hop flavor.

 

[beersk]

My samples tonight were not good. The v1 sample, did a mash hop on this one, was nasty. A weird burnt hop flavor (used EKG), burnt grass flavor. Ugh

Worse still, the v2 sample, which I did the full mash and then a proper boil with tettnang hops, also had the burnt grass flavor although not as strong as v1. The aroma was more than off putting.

Both were in the same bathroom that was ~69F during the day, and dropped at night along with the ambient temp.

Any trouble shooting thoughts? I dumped v1, and highly doubt v2 will age into something tolerable.

Did you notice any burnt material to the bottom of the kettle while cleaning? I had to stir while it was heating because I noticed some stuff wanting to stick to the bottom (which would have burned). I'm guessing it was starches.

Also, maybe these lower gravity beers are more sensitive to fermentation temperatures. Maybe 69F was too high?

 

[BrewnWKopperKat]

FWIW, Bell General Store has a kit (instructions are online) for Bell's new "Light Hearted" IPA.

I find "cold extraction" to be an interesting technique - but with the focus on process and on new / different flavors. But, ...

... honestly, if I were looking to brew classic, yet tasty, 3.5%-ish beers without a lot of effort, I'd be looking in places other than "cold extraction".

edit: link to related topic: https://www.homebrewtalk.com/forum/threads/low-abv-ipa-ish-style-beer-thoughts.675409/

 

[kmarkstevens]

Did you notice any burnt material to the bottom of the kettle while cleaning? I had to stir while it was heating because I noticed some stuff wanting to stick to the bottom (which would have burned). I'm guessing it was starches.

Any???There was a ton. That will learn me to not sample the wort when pitching the yeast.

I scorched both methods. The bottom of my brewers edge had a thick layer I'm still trying to clean off completely. Also had to soak and clean out the sous vide.

Will try again. I guess I'll have to just constantly stir the pot for both the mash and the hop boil.

@beersk How is your test coming along?

@BrewnWKopperKat If you want a 2-3.5%, then I wouldn't try this method either! Here's a wealth of information on sub 1030 beers: https://www.homebrewtalk.com/forum/threads/sub-1-030-beers.378450/

 

[BrewnWKopperKat]

I scorched both methods. The bottom of my brewers edge had a thick layer I'm still trying to clean off completely. Also had to soak and clean out the sous vide.

FWIW, the pictures associated with the PNWHC17 presentation show traditional equipment (see p 9, ...), probably with false bottoms and most of the process diagrams include a Lautering step.

 

[beersk]

Any???There was a ton. That will learn me to not sample the wort when pitching the yeast.

I scorched both methods. The bottom of my brewers edge had a thick layer I'm still trying to clean off completely. Also had to soak and clean out the sous vide.

Will try again. I guess I'll have to just constantly stir the pot for both the mash and the hop boil.

@beersk How is your test coming along?

@BrewnWKopperKat If you want a 2-3.5%, then I wouldn't try this method either! Here's a wealth of information on sub 1030 beers: https://www.homebrewtalk.com/forum/threads/sub-1-030-beers.378450/

Man, that sucks. I haven't tried mine cold and carbonated yet. Planning to sample this weekend.

@BrewnWKopperKat I'm not sure that traditional lautering really applies to this method as it is nearly impossible to get clear wort from the mash. I think this starch scorching or sticking to the bottom of the kettle is just something one has to deal with in this method.

 

[bierhaus15]

A better process for very low ABV beers (0.5%) is via arrested fermentation. This process preserves much of the hop and malt character of beer and is the same way many breweries make NA without expensive alcohol filtration systems.

In short, you brew a 1.030 beer of any style you want - dark beers and ipa's seem to work best - and ferment the beer with a non-sulfur and low diacetyl forming lager yeast at very cold temps, around 38F. When the ABV reaches 1.0-2.0%, you cold crash the beer and stop the fermentation. The yeast is removed (finings) and the beer is blended with deaerated water to 0.5% or whatever ABV you want.

I've done the following to make 0.5-1.0% ABV hoppy lagers and they are better than the commercial stuff. I recommend fermenting in a corney keg (short diptube) and you can then easily transfer into another keg with DA water to fine and carbonate. There are other details that help, but that's the basic process.

 

[Vale71]

When the ABV reaches 1.0-2.0%, you cold crash the beer and stop the fermentation. The yeast is removed (finings)

Low temperatures NEVER stop fermentation, they only slow it down and finings don't even get close to completely removing yeast. The only sure way to avoid issues from severe gushing up to bottle bombs is filtration followed by pasteurization (at best bottle pasteurization as partially fermented beer has very low microbiological stability) which are techniques that are well beyond the reach of most if not all homebrewers.

 

[RPh_Guy]

Low temperatures NEVER stop fermentation, they only slow it down and finings don't even get close to completely removing yeast. The only sure way to avoid issues from severe gushing up to bottle bombs is filtration followed by pasteurization (at best bottle pasteurization as partially fermented beer has very low microbiological stability) which are techniques that are well beyond the reach of most if not all homebrewers.

His process obviously can't be applied to bottled beers.

 

[Vale71]

His process obviously can't be applied to bottled beers.

Not to kegged beers either. While it's true that you can vent excess pressure from a keg to prevent explosion this will not void the other effects of continued fermentation, such as attenuation and ABV increasing all the way to full attenuation. His claim that the beer is stable when processed in the way he describes is therefore still completely false.

 

[RPh_Guy]

Hold on chief, let's look at some additional facts.
Since you like to play the semantics game, he never said the beer was "stable". Also remember we're dealing with home brewing; the keg won't be sitting at room temp. Cold temperature drastically slows fermentation so further attenuation likely won't be an issue in the timeframe that the beer is consumed.

This method of temporary cold stabilization is also used by some cider makers who want a sweet lightly sparkling cider without the effort of pasteurization or fining + chemical stabilization + force carbonation.

Also consider the numbers.
If a 1.030 beer is fermented to 2% ABV, that's a s.g. of 1.015. dilute that to 0.5% ABV and you get 1.004, of which only 0.002 is still fermentable. 1-2 extra volumes won't cause a chilled keg to explode, right? Or is that "completely false" too?

 

[bierhaus15]

^^ Yep.

Not to kegged beers either. While it's true that you can vent excess pressure from a keg to prevent explosion this will not void the other effects of continued fermentation, such as attenuation and ABV increasing all the way to full attenuation. His claim that the beer is stable when processed in the way he describes is therefore still completely false.

And while this is not an ideal process, I can assure you there are micro brewers that are doing this same process without ANY pastuerization. And what's more, you can buy those products in cans. That sit on the shelf! Amazing.

 

[Vale71]

^^ Yep.



And while this is not an ideal process, I can assure you there are micro brewers that are doing this same process without ANY pastuerization. And what's more, you can buy those products in cans. That sit on the shelf! Amazing.

Sorry but I have to call bullcrap on that. Without any stabilization those cans won't last long stored at room temperature, period.

 

[Vale71]

Hold on chief, let's look at some additional facts.
Since you like to play the semantics game, he never said the beer was "stable". Also remember we're dealing with home brewing; the keg won't be sitting at room temp. Cold temperature drastically slows fermentation so further attenuation likely won't be an issue in the timeframe that the beer is consumed.

This method of temporary cold stabilization is also used by some cider makers who want a sweet lightly sparkling cider without the effort of pasteurization or fining + chemical stabilization + force carbonation.

Also consider the numbers.
If a 1.030 beer is fermented to 2% ABV, that's a s.g. of 1.015. dilute that to 0.5% ABV and you get 1.004, of which only 0.002 is still fermentable. 1-2 extra volumes won't cause a chilled keg to explode, right? Or is that "completely false" too?

I was addressing the general claim that "fermentation is stopped" and that finings "remove the yeast" which are of course total nonsense. Of course if you let the beer reach significant attenuation and then dilute that with 4-5 parts water to 1 part beer continued fermentation won't affect the resulting beverage much. This will become however completely irrelevant as said beverage will taste so awful (like heavily watered-down, partially fermented beer as a matter of fact) that nobody will care to drink it anyway. As for storing the beer so cold that fermentation will slow down, he proposed fermenting at 38°F. Unless you serve your beers colder than that you will have to warm the keg up sometime prior to tapping it and how is that going to do anything but accelerate fermentation?

While partial fermentation has been extensively tried in commercial operations this is always done with proper stabilization prior to packaging. This has also been largely abandoned as the resulting beverage tastes exactly like partially fermented beer, which is not that great after all.

P.S. As for him never saying that the beer was "stable" then what did he mean when he claimed that he could stop fermentation and remove yeast? Who's playing the semantics game now, chief?

 

[bierhaus15]

Again, this is a home brewing forum where people are largely making beer with plastic buckets. Obviously my previous 50 word post didn't get into the nitty-gritty details of the whole process. Thanks for pointing that out though. Wouldn't want a person who is making NA beer in their basement with toilet parts to think their beer was completely shelf stable!

And if you have a better method for making home brewed NA beer that doesn't involve crossflow filtration technology, do go ahead and share that info with everyone.

 

[RPh_Guy]

I was addressing the general claim that "fermentation is stopped" and that finings "remove the yeast" which are of course total nonsense.

Your point is taken, however a guy over in the cider forum has successfully stabilized ciders solely by cold crashing and racking (repeatedly), so it's not impossible.
The point also stands that the beer is plenty stable enough to keg. His method is valid for the purpose at hand. However I think a high flocculation low attenuation ale strain like WLP002 is way better suited for that method. I would almost guarantee that once you crash and rack that it wouldn't start again.

I agree commercial beers need some kind of chemical/mechanical/thermal stabilization beyond cold crash.


Back on topic...

I'm not sure that traditional lautering really applies to this method as it is nearly impossible to get clear wort from the mash. I think this starch scorching or sticking to the bottom of the kettle is just something one has to deal with in this method.

I'm a little curious about this statement. It's unclear to me (no pun intended) exactly what lautering method you used. I'm thinking you didn't use a traditional mash tun with extensive vourlaufing or recirculation, right?

 

[Vale71]

Wouldn't want a person who is making NA beer in their basement with toilet parts to think their beer was completely shelf stable!

Yes, we wouldn't want that as this could result in something blowing up in their face and possibly causing serious injury...

I would also like to know where you think somebody making beer with toilet parts is going to get de-aerated water for post-fermentation dilution?

 

[Vale71]

And if you have a better method for making home brewed NA beer that doesn't involve crossflow filtration technology, do go ahead and share that info with everyone.

At the risk of going too much off topic I'll bite.

Buy yourself a Unitank. Any one of the currently availbale models is fine as long as it is pressure-capable and has some form of temperature control (either jacket or coil).

Brew your beer as you normally would (adjustments such as lower IBUs and more Caramalts to compensate for lack of alcohol will have to be implemented by trial-and-error) but only spund to minimal pressure (say 0.1 bar) at the end.

When the beer is fully fermented and conditioned (then and only then as this process WILL kill the yeast and stop maturation) switch from cooling to heating the fermenter by circulating 90°C water instead of glycol. Slowly increase the temperature to about 84-85°C while leaving the spunding valve set to minimal pressurization. Temp increase should be slow to avoid CO2 being released too violently possibly leading to excessive foaming. At the target temperature CO2 solubility will be almost zero so almost all of the dissolved CO2 will be released through the spunding valve while at the same time preventing any oxygen ingress.

Hold target temperature while regularly taking samples and measuring FG. To avoid excessive losses it's best to use a refractometer. As alcohol evaporates redings will steadily increase (with a hydrometer) or decrease (with a refractometer). Once the reading has been stable long enough (drawing a graph can help detect an asymptotic condition) turn off heating and start cooling rapidly while applying pressure with a CO2 bottle to prevent implosion.

The resulting NA beer will have to be force carbed once fully cooled as carbonation will be nearly zero at the end of the process.

This process will have the added advantage of pasteurizing the beer thus compensating for the reduction in stability resulting from alcohol removal.

It's not something you can do with plastic buckets but it's certainly withing the reach of advanced homebrewer who might even already be working with Unitank-style fermenters.