Lagering is useless

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No it doesn't do that at all. The paper shows that lager beer that is fermented relatively warm and then undergoes a diacetyl rest (15°C for 5 days) does not undergo significant changes during 1 moth of cold storage (either with yeat or without) as far as non-volatile substances suck as VDKs and acetaldehyde go. Bamforth himself openly admits that changes in volatile substances, which could have a very large impact on perceived flavor, were not investigated at all.
So I'd more accurately say that the study concludes that if you're a commercial brewery intent on producing a bland, light lager and only care about the most fundamental fermentation products but not aroma or flavor then cold storage for you is definitely useless.
 
No it doesn't do that at all. The paper shows that lager beer that is fermented relatively warm and then undergoes a diacetyl rest (15°C for 5 days) does not undergo significant changes during 1 moth of cold storage (either with yeat or without) as far as non-volatile substances suck as VDKs and acetaldehyde go. Bamforth himself openly admits that changes in volatile substances, which could have a very large impact on perceived flavor, were not investigated at all.
So I'd more accurately say that the study concludes that if you're a commercial brewery intent on producing a bland, light lager and only care about the most fundamental fermentation products but not aroma or flavor then cold storage for you is definitely useless.

Relatively warm? They used BSI Czech Lager yeast the manufacturer has two versions, paper doesn't specify which one was used but for either strain their 10C fermentation temp would have been in the low end of the range specified by the manufacturer...

BSI–800 Czech Lager 1
Apparent Attenuation: Medium to High
Flocculation: Medium
Fermentation Range: 48-60°F
Description: Original Czech Pilsner Lager strain. Somewhat dry with a malty finish.
Compares to WLP800 Pilsen Lager**

BSI–802 Czech Lager 2
Apparent Attenuation: High
Flocculation: Medium
Fermentation Range: 48-55°F
Description: Produces dry, crisp lagers with low diacetyl. Best for Bohemian pilsner lagers.
Compares to WLP802 Czech Budejovice Lager**
 
I agree that certain parameters must be addressed upstream as opposed to downstream, but simply reading the conclusion indicates that if they are so addressed, then Lagering is of no benefit. (I.E, useless)

They also use terms such as nefarious whereby to describe the ethereal and mystical connotations historically assigned to Lagering, which their study did not find. They clearly paint Lagering in highly negative terms.
 
Yes, 10°C is warm fermentation if compared to traditional lager fermentation profiles which have the yeast pitched at 4-6°C and the temperature never rising above 8°C and then slowly dropping to around 0°C once FG is reached, never ever even coming in the vicinity of higher temperature such as the 15°C reached in the experimental batch. Commercial breweries don't even look at the manufacturer's recommendations.
If you follow such a profile and then cut lagering short you will most definitely have issues with VDKs and acetaldehyde. I've experienced my shares of diacetyl bombs in small German brewpubs who clearly followed a tradional cold fermentation profile but then cut the lagering short for reasons of cost cutting. In some quite severe cases I could smell the waitress coming to my table the stench of diacetyl emanating from the beer she was carryng was so bad. In the interest of full disclosure I must say that not only am I trained in sensory analysis but my sensitivity to diacetyl has been tested and it's as low as 0.06 mg/l which is half the threshold quoted in the literature, which is of course an average for the general population.

P.S. I'm not saying this type of fermentation profile is never used in commercial brewing, just that it already counts as a more modern, accelerated fermentation and maturation profile even though it does not go all the way to warm pressure fermentation and maturation.
 
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I agree that certain parameters must be addressed upstream as opposed to downstream, but simply reading the conclusion indicates that if they are so addressed, then Lagering is of no benefit. (I.E, useless)
Again, they have been proven to be useless only if you choose to ignore the flavor and aroma aspects, which Dr. Bamforth did as he himself states in the conclusion. I'm sure this if more than enough for the likes of Miller and Coors but that still does not mean the statement can be generalized to all aspects of beer maturation.
 
In the opening statement paragraphs as well as in their conclusion it is specifically flavor impacting chemical changes that they were trying to detect, albeit that they did not detect any statistically meaningful changes. I quote:

As reported in the present paper, we have been unable to show that there is a convincing change in the level of any flavour relevant substance in maturation of pilot scale and commercial brews.
 
The statement after that reads:

The present paper has not focused on volatile sub-
stances; however, it is amply documented that the key entities
such as the esters, sulphur containing molecules, vicinal diketones
and carbonyl substances (such as acetaldehyde) should be con-
trollable by competent fermentation and upstream process prac-
tices

What it basically says is: "There is no impact on volatile flavor-active substances because they can be addressed during other phases of beer production and that's what you should do, period." It's a bit self-serving IMHO. What if you follow a more traditional cold fermentation profile which will result in reduced fermentation vigor paired with an increase in the production of, for example, sulphur compounds? According to Dr. Bamforth this is solely your fault because you were not "competent" in your practices which is judgemental and also a bit offensive IMHO.
 
The intentionally inflammatory language sounds like Bamforth trolling the internet to me. Anyone else and the editors/peer reviewers probably would have taken it out. Bombastic conclusions aside, the analytical technique involved was pretty interesting. A 600 MHz Bruker NMR is a serious piece of equipment. I had to google metabolomic analysis and found this article: NMR Analysis to Characterize Beer Profiling

Be interesting to see more studies like these.
 
Interestingly, I recently heard Charlie remark that he had actually "lost count" of the number of flavor active compounds in beer.
 
I remember a talk I heard Bamford give where he spent a lot of time talking about the research showing how cold lagering/conditioning made a difference, and there was a big difference between 38F and 32F (the colder the better was his conclusion).

Science is iterative and communal - it is seldom absolute truth, but our best efforts. That doesn't demean or devalue it, in fact, it elevates the enterprise.

Anecdotally, I find a couple of weeks of cold conditioning does my beer a world of good, but I've also made beer that was just fine without it.
 
I remember a talk I heard Bamford give where he spent a lot of time talking about the research showing how cold lagering/conditioning made a difference, and there was a big difference between 38F and 32F (the colder the better was his conclusion).

Science is iterative and communal - it is seldom absolute truth, but our best efforts. That doesn't demean or devalue it, in fact, it elevates the enterprise.

Anecdotally, I find a couple of weeks of cold conditioning does my beer a world of good, but I've also made beer that was just fine without it.

Bamforth's research and discussions about cold conditioning were why I opted for a fermentor in a freezer instead of glycol. I cold crash everything at below 30F these days. As I remember it the research pointed out that the cold crashing at below 30 for 1 day was better than 35 for a week. Something like that. But this wasn't about lagering on yeast.

Even in the linked experiment in this book the "unlaggered beer" was filtered to remove all yeast and the stored at -1C for a month. The lagered beer was unfiltered and stored a bit warmer, 2C, for a month before packaging and testing.
 
The English have a saying about making lager, "Have a few pints of ale and then visit the loo to make lager" or something to that effect.
I'm sure BMC would pay for a study to show that lagering is useless, that would certainly save money. He was Annheuser-Busch endowed prof at UC Davis til 2018.
 
As I remember it the research pointed out that the cold crashing at below 30 for 1 day was better than 35 for a week.
It was probably about chill haze. For effective chill haze formation (a prerequisite step for later removal) you need to get as close as possible to the freezing point in order to get those protein-polyphenols complexes to really bunch up permanently. Considering homebrewed beers are usually not filtered and cannot achieve the clarity of commercial filtered beers it is questionable whether this is really worth the effort of possibly slowing down other processes that contribute to flavor maturation and development.
 
I'm sure BMC would pay for a study to show that lagering is useless, that would certainly save money. He was Annheuser-Busch endowed prof at UC Davis til 2018.

I'm sorry I don't follow the rationale here. BMC can't market a Bamforth NMR study to their customers. I don't think this was the result they would have been hoping for.

The BMC brewer has to decide just like anyone else whether or not to follow the process indicated by the data. Someone has a way to save cost on production, will it impact the quality of the product and if so by how much? If the data had shown a flavor compound fingerprint that changed over time with lagering they might have used this as a quality control test to confirm the beer was ready to package potentially saving days or weeks of conditioning time. But the experiment was a bust and no such signal was found.
 
It was probably about chill haze. For effective chill haze formation (a prerequisite step for later removal) you need to get as close as possible to the freezing point in order to get those protein-polyphenols complexes to really bunch up permanently. Considering homebrewed beers are usually not filtered and cannot achieve the clarity of commercial filtered beers it is questionable whether this is really worth the effort of possibly slowing down other processes that contribute to flavor maturation and development.

haha yep that was the study. you are right it was a study about precipitating haze forming particles in lager beer and probably not relevant to production of modern IPAs where haze is more or less expected. But I'll keep doing it for now I guess.
 
I'm sorry I don't follow the rationale here. BMC can't market a Bamforth NMR study to their customers. I don't think this was the result they would have been hoping for.

The BMC brewer has to decide just like anyone else whether or not to follow the process indicated by the data. Someone has a way to save cost on production, will it impact the quality of the product and if so by how much? If the data had shown a flavor compound fingerprint that changed over time with lagering they might have used this as a quality control test to confirm the beer was ready to package potentially saving days or weeks of conditioning time. But the experiment was a bust and no such signal was found.
Can still lager and tell the customer you lager...just do it for a much shorter time. Money saved.
I know AB makes a big deal about keeping it real like Adolphus used to brew...but honestly they're a LONG way from the way Adolphus used to do it.
 
AFAIK you could legally sell an ale as a lager as in general there is no binding definition of what constitutes one or another. As a matter of fact, all mass-produced lagers have moved or will move shortly to warm pressure fermentation although they still use yeast strains that are bottom-fermenting but I don't think there would be anything legally preventing them from using an ale yeast other than the fact that the beer will no longer taste like a mass-produced lager which could cause customer acceptance to decline.
 
(Sigh) Yet another foundation of beer and brewing knowledge that has been upheld for centuries being mocked and questioned by this generation. Do they ever lighten up? Seriously

Philosopher Arthur Schopenhauer made this rather astute observation:
All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident.
 
What it basically says is: "There is no impact on volatile flavor-active substances because they can be addressed during other phases of beer production and that's what you should do, period." It's a bit self-serving IMHO. What if you follow a more traditional cold fermentation profile which will result in reduced fermentation vigor paired with an increase in the production of, for example, sulphur compounds? According to Dr. Bamforth this is solely your fault because you were not "competent" in your practices which is judgemental and also a bit offensive IMHO.

But Bamforth is right, though. ;)

I understand your point as well. Bamforth should not be promoting his *opinion* as *fact* in a scientific paper.

Still I do agree with him. All that stuff can and should easily be knocked out as part of fermentation. Perhaps traditional lagering is flawed.
 
Interesting read and great debate. @Vale71 your observations and insights are very much appreciated.

I, for one, will continue to lager regardless.

Some amount of post fermentation cold conditioning is obviously beneficial to the flavor of all beers and more importantly because I enjoy taking part in the tradition.
 
It's sort of ironic how for Covid-19 the mantra is to "follow the science", while for beer brewing the mantra is effectively the opposite, or rather it is something akin to "don't follow the science, follow the tradition".

Traditionally, the earth was the center of the universe, and the sun and planets revolved around the earth (which was flat).
 
It's sort of ironic how for Covid-19 the mantra is to "follow the science", while for beer brewing the mantra is effectively the opposite, or rather it is something akin to "don't follow the science, follow the tradition".

Traditionally, the earth was the center of the universe, and the sun and planets revolved around the earth (which was flat).

There's a difference between a traditional process and an archaic belief. Taking an argument to its most extreme logical ending serves only to derail the argument and escalate it to a series of extreme analogies, it doesn't add benefit.

But as you've already agreed, this study does not prove that lagering is useless, only that is it useless for reducing VDK's and acetaldehyde. I would be more inclined to believe a (well constructed) study using a trained sensory panel tasting pre Lagered and post Lagered beer.

There are simply too many flavor active compounds in beer to say that lagering has zero effect on all of them based on this study. Additionally taste is a complex neurological process and is unique to the individual. So the best statement we could ever prove or disprove is that

"On average, an individual with sensory training cannot distinguish between a beer that has been Lagered and one that has not"
 
Still I do agree with him. All that stuff can and should easily be knocked out as part of fermentation. Perhaps traditional lagering is flawed.
In that case Dr. Bamforth is kindly invited to prove it and not just postulate it. Also, flavor development goes well beyond VDK and actatldehyde abatement.
 
But as you've already agreed, this study does not prove that lagering is useless, only that is it useless for reducing VDK's and acetaldehyde.
That's not even what this study proves. VDKs and acetaldehyde were not even measured as part of the study. Their reduction was just assumed a priori. The study only measured the effects of yeast's metabolism on some clasees of non-volatile substances and showed that at lagering temperature there is no effect, as proven by the two test beers (one with yeast removed before lagering, one at the end of lagering) being identical in that respect. In a sense both beers were still lagered, just under different conditions.
 
It looks like roughly 80 flavor related markers (substances) were tracked via NMR for this study. Not just a couple. One might presume that they chose these 80 for good reason.
 
One interesting fact that emeges from the study though is the aspect of yeast autolysis. Autolysis is clearly detected but already at the end of fermentation. It then does not increase either in the filtered (as would be expected) or in the unfiltered beer. Keep in mind that the unfiltered beer was still removed from the bulk of the yeast by transferring from the fermenter to kegs. This show that even at a small scale (127 lite batch) autolysis is indeed a factor, with temperature being very effective at preventing further autolysis after primary. The unfiltered beer was stored at near freezing temperature whereas fermentation was conducted at temperatures as high as 15°C.
 
It looks like roughly 80 flavor related markers (substances) were tracked via NMR for this study. Not just a couple.
Only non-volatiles. Volatile substances have a much greater impact on flavor and aroma perception as they can actually get to your nose without you having to inhale the beer which would be rather unpleasant. :p
 
A couple thoughts this morning...

According to the definition used by the authors of this paper it would seem virtually all unfiltered kegged homebrew could be considered to have been lagered for some period of time. Doesn't make them all lagers but they have all been lagered.

My take on the authors interpretation of the results is that while lagering may have been historically useful for for cleaning up flaws in beer, current brewing practices are capable of eliminating those flaws during mash and fermentation. Improvements in ingredients and processes have reached point where it is possible to brew beer that simply does not have the flavor or aroma defects. Once the beer has reached the point of "cleanness" there is nothing left for the lagering process to "clean" and so it has no impact on defects that aren't there.

But I think it also says that for homebrewers and craft brewers who perhaps don't have same level of control over the ingredients or the process, lagering might still provide a useful safety net.
 
That's not even what this study proves. VDKs and acetaldehyde were not even measured as part of the study. Their reduction was just assumed a priori. The study only measured the effects of yeast's metabolism on some clasees of non-volatile substances and showed that at lagering temperature there is no effect, as proven by the two test beers (one with yeast removed before lagering, one at the end of lagering) being identical in that respect. In a sense both beers were still lagered, just under different conditions.
It looks like roughly 80 flavor related markers (substances) were tracked via NMR for this study. Not just a couple. One might presume that they chose these 80 for good reason.

You're right I apologize, I should have read the article completely. Vale I think your categorization of the substances as non-volatile is still too broad since he is specifically looking at the impact of yeast metabolites during lagering, not all non-volatile substances are metabolically active, yet may still have a flavor impact (such as polyphenols and some other hop derived compounds). So Silver, I think it might be more accurate to say

"The full scope of the flavor effects due to lagering are unknown, however it is not a process affected by yeast metabolism, assuming you have eliminated sulfur compounds, VDK's and acetaldehyde via your primary fermentation regime"

rather than "lagering is useless" (which I recognize as being an attention grabbing title, so bravo to that).
 
I would say the most RELEVANT study would be to have a trained panel of sensory homebrewers taste pre-lagered and post-lagered beer, NOT BLIND.
All my tastings of my own beer are not blind...I know what I did.
Usually if I have to cut corners, I beat myself up about it and think I can tell the difference. It's just who I am.
Lager I will.
 
I would say the most RELEVANT study would be to have a trained panel of sensory homebrewers taste pre-lagered and post-lagered beer, NOT BLIND.
All my tastings of my own beer are not blind...I know what I did.
Usually if I have to cut corners, I beat myself up about it and think I can tell the difference. It's just who I am.
Lager I will.
I think you are supposed to use green font here.
 
It seems to me like lagering might be insurance. Much like the advice the 1-2-3 rule for homebrewing. Sounds neat, but at the end of the day the beer is done when it's done in both cases. Pascal's Wager
 
I would like the same study to be done with the entire stages needed to make a great Eisbock to say lagering has no bearing.
 
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