bottle temps

[well_bucket_brews]

i have seen while looking at some threads here that the fermenting temps and bottling temps are different animals. it appears that you can control the fermenting temps with swamp coolers and the like, but how do you control bottle temps, or even get a reading of the temp of beer in the bottle?

thanks!

 

[Mojzis]

You don't need to get a reading of the temperature of the bottles. Because fermentation is exothermic it produces heat, which is why you need to control the temps. Very little fermentation is going on in the bottles. They will be whatever your house/apartment temperatures are. Keep in mind that they will also absorb and lose heat slower than air so their temps should remain stable if you don't have large fluctuations in house temp.

Lastly, keep in mind that you don't really have to control the bottle conditioning temp. If its higher or lower than the suggested 70F its not the end of the world. It may take longer or it may not. It all depends of the amount of yeast in the bottle, time, temp, alcohol content, etc. But in the ideal model 3 weeks at 70 is suggested.

 

[dozer5454]

Room temp is usually appropriate for most beers I do. The room sits about 70 degrees. 3 weeks at 70 degrees is a good rule of thumb.

 

[unionrdr]

Since the beer in bottles in in a sealed container,the normal temp range dosen't apply. The beer is well past initial fermentation at this point where temps are more critical. Hence keeping the bottles near 70F to carbonate & condition,since so little fermentables are used with the smaller amount of yeast still present/needed for the carbonation to commence.

 

[Mojzis]

Since the beer in bottles in in a sealed container,the normal temp range dosen't apply.

Not debating, but may you demonstrate the science of this? You learn something new everyday and this may just be mine for today.

 

[unionrdr]

Not debating, but may you demonstrate the science of this? You learn something new everyday and this may just be mine for today.

Most of the off flavors in beer come from by products of fermentation that are normally produced. But in such small quantities that they aren't percieved. But get initial ferment temps too high,too much sugar in the recipe,shock the yeast or underpitch,etc & these chemicals can be produced in sufficient quantities to be smelled &/or tasted. Brining the temp into normal range somehow helps at the begining of initial fermentation to prevent all this from happening in great enough quantities to be percieved.
Then when FG is reached,I've found on average it takes 3-7 days after FG (when all the fermentables have been eaten by the yeast) for them to then turn their attention to these by products of fermentation. If they aren't in large enough quantities to keep the yeast from converting them to harmless products,or normal ones depending,you get cleaner tasting beer. Hope this clears it up a little.
Now,after all this goes on in the fermenter,with it's airlock or similar device that can release excess gasses & is still in contact with the yeast cake,it cleans up & the perios of harm is past. This is in regard to ferment temp ranges where cleaner beer is produced,or high temps etc can still effect it during said initial fermentation. After that,these dangers are past,but can still be cleaned up. just not produced anymore.
The bottles being capped,is the "sealed environment" I'm referring to,opposit the fermenter environment that can off gas,etc. It seems that at this point,past initial fermentation,only the yeasts low temp range can effct it while carbonationg & conditioning the beer. Higher temps,like the 70F mentioned for this step of the process,will not hurt the beer in any way,since it's past initial fermentation where these excess amounts of by products are produced. The sealed bottles force the co2 to pressurize the head space,7 start going into the beer. The 3-4 weeks mentioned is the normal amount of time it takes for the yeast to eat the priming sugar,produce the co2 that makes the bubbles,& a small amount of additional alcohol. Being trapped,it gives carbonation during fridge time,since cold liquids more readilly absorb it than warm ones. It basically seeks equalibrium between the gas in the head space & that absorbed into the beer.
Sp low temps at bottling can slow the yeasts' matabolism,but high temps just make them work faster at this point. And such a small amount is in activity at this point,no worries as during initial fermentation.

 

[Mojzis]

Right, I know that most secondary products of fermentation are catabolized once initial fermentation is complete. That's if you didn't ferment too high or brew with chlorinated water, etc. I was wondering on how the sealed system would change the temp range. With the amount of fermentation going on (minimal) the secondary products created by elevated temps during bottle conditioning won't be noticed. Is that what you meant? Not the fact that it's a sealed system, but rather that the amount of fermentation going on is too small in order to generate a perceivable off taste?

 

[BlackGoat]

Just adding that the bottle conditioning temps are just a guide, its not as much of a hard-and-fast rule as worrying about your fermentation temps. Most of us don't bother controlling the conditioning temps, we just store our beer in a part of our house as close to 70 as possible. For me, I have a closet that sits at about 68-70 throughout the year and that is where I do my conditioning.

 

[unionrdr]

Right, I know that most secondary products of fermentation are catabolized once initial fermentation is complete. That's if you didn't ferment too high or brew with chlorinated water, etc. I was wondering on how the sealed system would change the temp range. With the amount of fermentation going on (minimal) the secondary products created by elevated temps during bottle conditioning won't be noticed. Is that what you meant? Not the fact that it's a sealed system, but rather that the amount of fermentation going on is too small in order to generate a perceivable off taste?

Since most fermentation by products that are percieved as off flavors in larger quantities come in from initial fermentation,that threat is gone at this point. Being a sealed system keeps any chance of air out of the equasion. You need food,air & warmth for nasties to propogate. Thes chemicals can also be "cleaned up" to a smaller degree in the bottles as well. If the 3-7 days clean up time were allowed in primary,this extra time can help finish up the "cleaning" process a little.
The amount of fermentation going on in the bottle is small,so combined with the lack of air,the little nasties don't stand a chance. & being past initial fermentation,no by products would be produced in percievable quantities.