Low Alcohol Beer by evaporation

I recently saw an article about creating a low alcohol beer by putting the finished beer into an oven at 180 degrees. The idea is, since alcohol boils at about 172, one could reduce the amount of alcohol in a beer.

As my fondness for IIPAs and other strong brews grows, my tolerance for alcohol is waning. So lowering the alcohol this way, unlike brewing a "lite" beer, would seem to be a technique that bears investigation. But there has to be some "gotchas". And I don't really understand the chemistry:

1. How long would it take to reduce the alcohol significantly?
2. At 180 degrees, what is likely to happen to the hop oils? I've read of people adding all the flavor hops at flameout, then delaying cool down in order to get good hop flavor.
3. Is there a relationship between the various hop oils to the quantity of remaining alcohol?
4. I would think aromatics could be re-added by dry hopping in the keg. Thoughts?

Anyone ever tried this?

Rich

Why not just reduce the grain bill?

Only thing i might be able to answer is question 4. Dry hopping shouldn't be an option after alcohol is removed because hop oils are only heat or alcohol soluable. The only possibility ,and i'm not sure if this is what you were suggesting or if you were talking about at the original brew session, but it would be to add hops towards the end of the cook in the oven. That should pull aroma and flavor just like flameout hops

ConnorPPrice said:

Why not just reduce the grain bill?

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The original article was about low to no alcohol beers. It was about the idea of making a drinkable N/A beer. lowering the grain bill would compromise malt flavor

I think this could work, but you'd lose beer in the process. While a lot of alcohol would evaporate, you'd also lose some water along with it which could lead to some unbalanced flavors in the resulting liquid. Unless you somehow adjusted the recipe accordingly. Maybe you could brew the recipe with the final volume in mind, but there's no way of telling what it will taste like without sacrificing a few batches first.

jester5120 said:

The original article was about low to no alcohol beers. It was about the idea of making a drinkable N/A beer. lowering the grain bill would compromise malt flavor

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My mistake, I misread the OP. I thought this was looking for a relatively small reduction in alcohol to bring a beer more into session territory.

jester5120 said:

Only thing i might be able to answer is question 4. Dry hopping shouldn't be an option after alcohol is removed because hop oils are only heat or alcohol soluable. The only possibility ,and i'm not sure if this is what you were suggesting or if you were talking about at the original brew session, but it would be to add hops towards the end of the cook in the oven. That should pull aroma and flavor just like flameout hops

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I was suggesting "maybe" doing flavoring hops while removing alcohol, although I'm not sure it's necessary. The article seemed to think one would lose all the flavor and aroma at 180 degrees. That doesn't seem right to me, judging from how you can get some flavor from FWH. As I understand it, by letting the hops steep in the wort prior to the boil, the volatile oils and resins release, giving them more time to oxidize to more soluble compounds. Thus a greater percentage are retained during the boil. So....


For the aroma, I find MUCH more aroma doing a dry hop than a late hop, which is why I dry hop in the keg. I wasn't planning a "no alcohol" beer, so it would still work, I think.

nefarious_1_ said:

I think this could work, but you'd lose beer in the process. While a lot of alcohol would evaporate, you'd also lose some water along with it which could lead to some unbalanced flavors in the resulting liquid. Unless you somehow adjusted the recipe accordingly. Maybe you could brew the recipe with the final volume in mind, but there's no way of telling what it will taste like without sacrificing a few batches first.

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I hadn't thought of that, thanks. May just pull a gallon off a future batch just to see. Carb it up and give it a try.

yeah if there's still alcohol then dry hopping should work. I didn't think of this until just now but I think a lot of what gets rid of aroma is the violent boil so 180 I think would be fine. I know the reason they tell you not to dry hop in primary is because the movement of co2 kicks out all the aroma. I would think the same principle probly applies to the boil

RichBenn said:

I recently saw an article about creating a low alcohol beer by putting the finished beer into an oven at 180 degrees. The idea is, since alcohol boils at about 172, one could reduce the amount of alcohol in a beer.

As my fondness for IIPAs and other strong brews grows, my tolerance for alcohol is waning. So lowering the alcohol this way, unlike brewing a "lite" beer, would seem to be a technique that bears investigation. But there has to be some "gotchas". And I don't really understand the chemistry:

1. How long would it take to reduce the alcohol significantly?
2. At 180 degrees, what is likely to happen to the hop oils? I've read of people adding all the flavor hops at flameout, then delaying cool down in order to get good hop flavor.
3. Is there a relationship between the various hop oils to the quantity of remaining alcohol?
4. I would think aromatics could be re-added by dry hopping in the keg. Thoughts?

Anyone ever tried this?

Rich

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1. Nobody has ever done anything like this and verified success by directly measuring the remaining alcohol and decreased the alcohol by more than 50%. People who say it works just assume it works and never verify.

2. The hop oils are extremely volatile, heat some IIPA and your nose will tell you what is happening to the hop oils.

3. There is more ethanol than hop oil in an IIPA by orders of magnitude. You will destroy the hop character trying to get a third or half of the alcohol out.

4. Sure.

I would just make a San Diego Session Ale type beer (think Stone Levitation) if I wanted a 4% beer with IIPA like aroma. I think what you propose is a lot of work for a mediocre result.

Problem with this method is that the mole fraction of EtOH is so low. In a 6% ABV beer it is only 2%. At 82 °C (180 °F) the vapor pressure of EtOH over a 6% beer is 0.02*884 = 17.7. At the same temp. the vapor pressure of water is 0.98*389 = 381 mmHg. Thus for every ethanol molecule driven off 381/18 = 21 molecules of water escape. And, of course, as the alcohol concentration goes down the ratio becomes even less favorable. This is why a column is used in distillation and I guess you could use a column to just get rid of the alcohol - i.e. don't condense the vapors coming out of the column. The heat would still ruin the beer.

The "best" low alcohol beers are apparently made using dialysis to separate out the alcohol. Have you ever had one you liked?

Thanks, all! I figured there were problems with this idea, and you've saved me the time experimenting with it. Guess it's back to the late hopped Pale Ales and lower consumption of the others...

There is this wonderful stuff called dihydrogen monoxide which will not only reduce the alcohol concentration but turns into free beer in the fermentor or keg or wherever you add it to the beer. The potential downsides are 3
1)It must be sterile before adding it to your beer
2)It must be free of dissolved oxygen
3)It reduces the alcohol content but also reduces the bitterness, hop flavor and malt flavors proportionally.

ajdelange said:

There is this wonderful stuff called dihydrogen monoxide which will not only reduce the alcohol concentration but turns into free beer in the fermentor or keg or wherever you add it to the beer. The potential downsides are 3
1)It must be sterile before adding it to your beer
2)It must be free of dissolved oxygen
3)It reduces the alcohol content but also reduces the bitterness, hop flavor and malt flavors proportionally.

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You are kidding, right? The MSDS for this stuff, among other things, lists:

CHRONIC HEALTH HAZARDS: May cause bloating, abdominal distension, frequent urinary activity, coughing, ear aches, epidermal distortions, and more.
SIGNS/ SYMPTOMS OF EXPOSURE: Extreme wrinkling of skin; gagging; coughing; responsible for injury, death, and property damage all over the world.

There is also group seeking to ban the stuff, with lines like: "Its basis is the highly reactive hydroxyl radical, a species shown to mutate DNA, denature proteins, disrupt cell membranes, and chemically alter critical neurotransmitters."

Not something the average Joe (or me) ought to be messing with......

Rich

RichBenn said:

I recently saw an article about creating a low alcohol beer by putting the finished beer into an oven at 180 degrees. The idea is, since alcohol boils at about 172, one could reduce the amount of alcohol in a beer.

As my fondness for IIPAs and other strong brews grows, my tolerance for alcohol is waning. So lowering the alcohol this way, unlike brewing a "lite" beer, would seem to be a technique that bears investigation. But there has to be some "gotchas". And I don't really understand the chemistry:

1. How long would it take to reduce the alcohol significantly?
2. At 180 degrees, what is likely to happen to the hop oils? I've read of people adding all the flavor hops at flameout, then delaying cool down in order to get good hop flavor.
3. Is there a relationship between the various hop oils to the quantity of remaining alcohol?
4. I would think aromatics could be re-added by dry hopping in the keg. Thoughts?

Anyone ever tried this?

Rich

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First, I think it'd take quite a while to remove a significant portion of alcohol from such a large batch, I've done distillation in lab and it takes about 5 minutes to distill about 100 mL. If you're going for a completely NA beer I'd try heating it on the stove for about 2 hours.

2. I don't think it would isomerize the hop oils so your flavor would be maintained, but aroma might be lost. The method you describe for more hop flavor is really just the same as doing a 15 minute addition. By gaining flavor you sacrifice aroma, and by gaining bitterness you sacrifice flavor. It is a continuum based on boiling time.

3. I don't really understand the question. If youre asking whether you'll lose hop oils from this method, I doubt it.

4. If you're concerned Witt the solubility of hop oils to gain aroma you can simply make a hop tea, no problem. Hop oils are still soluble in water just less so than alcohol.

Overall I think this method would work. If doing all grain I would recommend exploring high mash temperatures and minimizing your grain bill. This will help to make the gap between your OG and FG much smaller thereby maintaining malt flavor but decreasing alcohol. And combination between high temp mashing and distillation will likely yield and close to NA beer.

RichBenn said:

You are kidding, right? The MSDS for this stuff, among other things, lists:

CHRONIC HEALTH HAZARDS: May cause bloating, abdominal distension, frequent urinary activity, coughing, ear aches, epidermal distortions, and more.
SIGNS/ SYMPTOMS OF EXPOSURE: Extreme wrinkling of skin; gagging; coughing; responsible for injury, death, and property damage all over the world.

There is also group seeking to ban the stuff, with lines like: "Its basis is the highly reactive hydroxyl radical, a species shown to mutate DNA, denature proteins, disrupt cell membranes, and chemically alter critical neurotransmitters."

Not something the average Joe (or me) ought to be messing with......

Rich

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Listen, the dangers that people tell you about dihydrogen monoxide do NOT hold water. They are purportedly 'experts' about this chemical, however whenever asked to name sources for the claims they make on the supposed toxicity of this substance, they fall laughably short. While they are grasping at straws, trying to stir up fear about this harmless substance (which, might I add, has been around for YEARS) the research is not being done. Wake up, sheeple!

jester5120 said:

The original article was about low to no alcohol beers. It was about the idea of making a drinkable N/A beer. lowering the grain bill would compromise malt flavor

Click to expand...

It is all about balance. Experiment with smaller grain bills and higher fermentation temperatures. A 1.012 finishing gravity is a 1.012 finishing gravity. Obviously it won't be EXACTLY the same but the balance should still be there. Milds are one of my favorite styles and I mash on the high side.

RichBenn said:

You are kidding, right? The MSDS for this stuff, among other things, lists:

CHRONIC HEALTH HAZARDS: May cause bloating, abdominal distension, frequent urinary activity, coughing, ear aches, epidermal distortions, and more.
SIGNS/ SYMPTOMS OF EXPOSURE: Extreme wrinkling of skin; gagging; coughing; responsible for injury, death, and property damage all over the world.

There is also group seeking to ban the stuff, with lines like: "Its basis is the highly reactive hydroxyl radical, a species shown to mutate DNA, denature proteins, disrupt cell membranes, and chemically alter critical neurotransmitters."

Not something the average Joe (or me) ought to be messing with......

Rich

Click to expand...

I'm no expert on the compound, but I did look at the website for the organization attempting to ban dihyrdrogen oxide. There basis is that it proces hydroxyl radicals which truly are know to mutate DNA. But what you may not know is that these hydroxyl radicals are everywhere in our body, they're produced in the mitochondria during oxidative phosphorylation, and they're produced by immune cells to kill bacteria. Our bodies are equipped to handle using an enzyme who's specific name escapes me. It's also the active form of hydrogen peroxide, should we ban that? I'm just say that's a pretty stupid reason to attempt to ban a substance.

I too think the dangers are over stated but, and I don't admit this often, all my beers contain some DHMO. At the same time I must report that the father of a boyhood friend of mine was killed by it. So, as with many other things in life, one just has to be careful with it.

As for the hydroxyl radical - I remember a Brewing Network broadcast in which Charlie Bamforth talked about how destructive it can be in beer. So again, if you plan to use it in your beer, please be careful with it.

Yeah, guys, maybe "banning" the product is overkill, but NOT something ANYONE should recommend to a novice. It's something that should be dealt with MUCH more carefully than a common household chemical. When the word "death" appears on an MSDS, it's not something to be trifled with! A Material Data Safety Sheet is NOT some document put out by crackpots. It's required by law that the manufacturer have it.

Dealt with liability issues with far more innocuous chemicals -- it's the kind of stuff that can get you sued if you take a cavalier attitude.

OK, back on topic -- AJ, I realize now I don't fully understand one statement you made earlier -- "...heat would still ruin the beer". Why would 180 degrees in itself be harmful to the beer, as in "what way"? People that do no chill report success, and that beer is kept at similar temps for a significant period.

Rich

Let me respond to that with a question I asked earlier. Have you ever tasted a dealcoholised beer you liked? I don't think it really matters how you do it but when you remove alcohol you remove other compounds as well and some of those are responsible for what makes beer beer. With heat it's more or less clear how this works. Lots of the flavors, and certainly the aromas, of beer are caused by volatile substances. That very word implies that these are substances that will fly off. When you heat anything volatile components become more volatile. Plus heat accelerates other reactions such as staling reactions. Beer which has been heated tastes "cooked". That's why if I know something is pasteurized I don't buy it.

Maybe I am overly sensitive to this and that's why perhaps you will want to ponder the question in the last paragraph.

ajdelange said:

there is this wonderful stuff called dihydrogen monoxide which will not only reduce the alcohol concentration but turns into free beer in the fermentor or keg or wherever you add it to the beer. The potential downsides are 3
1)it must be sterile before adding it to your beer
2)it must be free of dissolved oxygen
3)it reduces the alcohol content but also reduces the bitterness, hop flavor and malt flavors proportionally.

Click to expand...

a+

ajdelange said:

Let me respond to that with a question I asked earlier. Have you ever tasted a dealcoholised beer you liked? I don't think it really matters how you do it but when you remove alcohol you remove other compounds as well and some of those are responsible for what makes beer beer. With heat it's more or less clear how this works. Lots of the flavors, and certainly the aromas, of beer are caused by volatile substances. That very word implies that these are substances that will fly off. When you heat anything volatile components become more volatile. Plus heat accelerates other reactions such as staling reactions. Beer which has been heated tastes "cooked". That's why if I know something is pasteurized I don't buy it.

Maybe I am overly sensitive to this and that's why perhaps you will want to ponder the question in the last paragraph.

Click to expand...

Thanks, AJ. I guess I haven't tasted a de-alcoholised beer I like. However, I'm not fond of high adjunct beers either, and most of those beers tend to be that way. And I've never meant "no-alcohol", but rather "low alcohol".

It's the interaction of the alcohol and hops that I suspect is one key here, as beers like Pliny the Elder, Stone Ruination, and other highly rated IIPAs do not use darker, less fermentable malts and α-amylase saccharification to counteract the high hop bitterness and flavor, but rather avoid using much crystal and colored malts while using beta-amylase friendly 149-150 degree rests with sugar added late in the boil to help increase the quantity of fermentable sugars. Basically, alcohol is used to highlight the hops.

I'm well aware of the idea of increasing maltiness and mouthfeel and relying on late hop additions to make a relatively lower alcohol beer accept more hops. But that's a different tasting beer. Possibly a 3-4%% beer with 90 IBUs is going to taste bitter/wrong regardless of the technique to get it 3% alcohol.

In terms of the volatile compounds, that's the second suspicious area that originally got me to post here in the Beer Science area rather than General Techniques. But, like I said, the "no chill" movement, which keeps the temps high post boil(pre-fermentation), got me wondering about what kind of components actually get driven off/modified at sub boiling temperatures. There is even a group of individuals dumping in all their flavoring hops at flameout and letting it steep for an hour before cooling. (Bittering - boil, flavor - sub-boil, aroma - dry hop).

However, there is ethanol (and other compounds) in the post fermentation product, so it's possible that the same temperatures (170-200 F) will have a totally different effect when trying to drive/distill the alcohol off.