Fusel alchohol production

[ancapgeko]

I'm sure most here would agree that fusels are part of the flavor profile of many beers, in fact are the defining characteristic in some styles.
However, I think it is entirely appropriate to discuss methods to reduce certain unwanted characteristics.

 

[MalFet]

There seems to be no recognition in this thread that there is no scientific proof that fusels cause any problems, in fact they are a key component of the flavour profile of many beers.

Uhh...what? My scientific proof is that when I drink beers with excessive fusels they taste bad.

I don't think anybody here has suggested that fusels are all bad all the time, but excessive fusels is a real problem that people run into.

 

[theredben]

MalFet - I meant "bad fusels" in the respect that people believe them to cause hangovers. I completely understand not liking the taste of butanol , but unfortunately it seems we are stuck with them.

 

[vicratlhead51]

Fusel Oils are by definition bigger, they have one extra carbon atom. But you are correct in assuming that removing things in the size range of fusels will remove flavour compounds. You cannot filter beer on that level and still have beer come out the other end. But this product does not work by filtering based on size, it works with adsobtion.

There seems to be no recognition in this thread that there is no scientific proof that fusels cause any problems, in fact they are a key component of the flavour profile of many beers.

Yeah we kind of got off track a bit. I started the thread because a coworker asked if my homebrews ever gave me a headache. I assumed it would be overproduction of fusels but I was also curious if there were any mistakes somebody could make to brew a beer that caused bad hangovers or headaches. I'd love to hear any other reasons or causes.

 

[theredben]

All the evidence says that the most important factor in hangovers is the way you drink. Drink a beer with a glass of water before the next one and you will be better off regardless of what is in the beer.

 

[cklages]

There are numerous theories on what actually causes hangovers, here is a website that disusses a bunch of them:

http://hamsnetwork.org/hangover/

The one that I kind of subscribe to is the following

The Congener Hypothesis
Congeners are chemical compounds other than alcohol and water which are found in alcoholic beverages and which contribute to giving them a pleasing color and flavor and smell. Examples of typical congeners are amines, amides, acetones, polyphenols, methanol, and histamine.
In 1970 Dr. LF Chapman did an experiment to see whether congeners increase the likelihood of people having hangovers. Dr. Chapman gave one group of subjects bourbon whiskey, a beverage which is very high in congeners. Another group of subjects were given vodka which is very low in congeners. Both groups were given the same dosage of alcohol (1.5g/kg). 33% of the subjects who received the bourbon reported hangover, whereas only 3% of subjects who received vodka reported hangover.
There are a couple of studies (Woo et al, 2005, Bendtsen et al 1998) which suggest that the congener methanol may be involved in hangover. Methanol is also known as methyl alcohol or wood alcohol and is a highly poisonous compound which can cause blindness or death. The human body breaks methanol down into the toxic components formaldehyde and formic acid. Trace amounts of methanol are found in alcoholic beverages, but they are also found in orange or apple juices.
In order to test the hypothesis that methanol is responsible for hangover it would be necessary to conduct the following experiment: a mixture of pure ethanol and water would need to be compared to a mixture of ethanol and water which contained a trace of methanol and both of these should be compared to water containing a trace of methanol. If such an experiment were conducted it would work to confirm or disconfirm the methanol hypothesis of hangover. There are several other congeners which are also hypothesized to contribute to hangover, including isopentanol, ethylic acetate, and ethyl formate, etc. The hypothesis that these congeners contribute to hangover could be tested the same as the methanol hypothesis above. Such experiments have yet to be carried out.

 

[MalFet]

All the evidence says that the most important factor in hangovers is the way you drink. Drink a beer with a glass of water before the next one and you will be better off regardless of what is in the beer.

Hydration is certainly a part of the issue, but there is significant evidence to suggest that various kinds of toxicity are also at play. This article suggests that acetaldehyde is partly to blame. This article talks correlates hangover duration to rates of methanol metabolization. There are tons of other papers out there that identify other potential metabolites.

As for fusels: There is a lot of anecdotal evidence to suggest that beers with high fusel levels lead to headaches, but there isn't much evidence to back it up one way or another. One paper did explore the issue and even found that fusels lead to decreased headaches in mice (supposedly), but their sample was very small and I found their methodology a bit suspect. There is enough anecdotal evidence (including my own) correlating fusels and headaches that I'm still somewhat convinced by the link, but I'd don't think there is decisive info one way or the other.

The move to realize that dehydration is an important factor in hangovers certainly appears to be correct, but I would hesitate to say that it is "the most important factor" without some evidence. I've not seen anything that ranked these things, but would love to read anything you might have seen that says otherwise.

Edit: Good find cklages. The bourbon vs. vodka thing is very suggestive. Unfortunately, the decisive research has not yet been carried out, and (thanks to university IRB boards) likely never will be.

Edit2: One thing in favor of hydration, at least, is that it is something you can control. You can't easily make your kidneys or liver metabolize toxins faster, but you can make yourself have a big glass of water before you go to bed.

 

[theredben]

MalFet - While it would seem from my reply that I was infering that I think dehydration causes hangovers, what I really meant was that it both reduced the physical amount of beer you can consume and spread it out over a longer period of time. Same thing as drinking a big glass of water 30 minutes before a meal. No special chemical sequences, just less physical space for food.

I will see if I can find the link an interesting report on wine consumption. Seems that people say that when they go to europe they don't have a hangover afterwards, obviously because the wines are far superior /superiority complex. But when they look into the issue, people can drink the exact same bottle of wine in North America and get totally wasted, but it is mainly due to the way that it is consumed.

Found what I thought to be the link, but it doesn't seem to cite anything, I'll keep reading. The information about comsumption style is about 2/3 of the way down.

 

[theredben]

cklages - slightly off topic, but holy cow! 1.5g/kg of alchohol.

average person =~72kg x 1.5g = 108g alchohol. Spirits are 40% so, 108/0.4=
270g vodka/brandy. Given that with the alcohol it will be a little bit lighter than water you are still looking at around 3/4 cups!!!

 

[MalFet]

I will see if I can find the link an interesting report on wine consumption. Seems that people say that when they go to europe they don't have a hangover afterwards, obviously because the wines are far superior /superiority complex. But when they look into the issue, people can drink the exact same bottle of wine in North America and get totally wasted, but it is mainly due to the way that it is consumed.

Found what I thought to be the link, but it doesn't seem to cite anything, I'll keep reading. The information about comsumption style is about 2/3 of the way down.

I don't think anyone would dispute that hydration and manner of drinking is an important factor. But, I do think that people dismiss the importance of toxicity far too quickly these days. The proverbial baby got thrown out with the bath(tub gin), as it were.

 

[theredben]

Found a good one - http://pubs.niaaa.nih.gov/publications/arh22-1/54-60.pdf

When you read stuff like that, and they can't come up with a good answer, then you get an idea that there is no one "magic bullet" that makes a hangover. In that paper they reported that even mice injected with pure ethanol suffered a hangover the next day.

 

[MalFet]

Found a good one - http://pubs.niaaa.nih.gov/publications/arh22-1/54-60.pdf

When you read stuff like that, and they can't come up with a good answer, then you get an idea that there is no one "magic bullet" that makes a hangover. In that paper they reported that even mice injected with pure ethanol suffered a hangover the next day.

Interesting read. I very much agree that there is no one magic bullet. I suspect all of these are significant factors. Related to the dehydration is electrolyte imbalance. Where I live in South Asia, people suck lemons to beat a hangover. Slightly off topic, but I've got to say that the guy who figures out if mice are hungover or not has a really weird job.

 

[theredben]

The glory life of a grad student.