Cold crashing and bottling - question

[Popey]

On the basis that there is no such thing as a dumb question, here goes...

My Wilko triple hopped IPA has finished fermenting and I want to cold crash it to clarify it before bottling.
I'm planning on reducing the temperature in my fermentation fridge to 4 degrees for a few days.

My question is: should I let the temperature of the beer in the fermentation vessel come back up to ambient before bottling?

Thanks!

 

[Mavroz]

No, bottle away. When i used to make kits, i bottled straight from cold crash around 6 to 8 degrees (natural outside temps at the time).
The temperature when in the bottles will rise to ambient (keep in a warmer place), meaning carbing and conditioning should take place just fine.

 

[An Ankoù]

On the basis that there is no such thing as a dumb question, here goes...

My Wilko triple hopped IPA has finished fermenting and I want to cold crash it to clarify it before bottling.
I'm planning on reducing the temperature in my fermentation fridge to 4 degrees for a few days.

My question is: should I let the temperature of the beer in the fermentation vessel come back up to ambient before bottling?

Thanks!

I don't, but further to your question: when you're using a carbonation calculator, what do you enter in the temperature field, the temperature before cold crashing or the bottling temperature?

 

[Mavroz]

I used the approx ambient temperature the bottles will be stored in for carbonation.

 

[Popey]

Thank you everyone. I really appreciate your help.

 

[Drunkula]

what do you enter in the temperature field, the temperature before cold crashing or the bottling temperature?

It would be the temperature the beer was at when it finished fermenting and was kept at after that. If it finished at 20c and then you cold crashed you'd put in 20c. If it finished fermenting at 20c after 5 days but you didn't bother bottling until 10 days and for the last few days it warmed up to 23c you'd use 23c because some of the co2 would have been driven off.

 

[An Ankoù]

It would be the temperature the beer was at when it finished fermenting and was kept at after that. If it finished at 20c and then you cold crashed you'd put in 20c. If it finished fermenting at 20c after 5 days but you didn't bother bottling until 10 days and for the last few days it warmed up to 23c you'd use 23c because some of the co2 would have been driven off.

Correct. Although it was a question for Popey. The beer has finished fermenting and so no more carbon dioxide will be produced, which is a shame as it is more soluble at lower temperatures. That's assuming that the fermentation would continue fermenting at cold-crash temperatures anyway, which for most ale yeasts, it won't.

 

[Popey]

Correct. Although it was a question for Popey. The beer has finished fermenting and so no more carbon dioxide will be produced, which is a shame as it is more soluble at lower temperatures. That's assuming that the fermentation would continue fermenting at cold-crash temperatures anyway, which for most ale yeasts, it won't.

To be honest, I haven't used a calculator yet. I was going to add 7.5g of dextrose solution per 500ml (the recommendation on a video from Lovebrewing). Having looked at the calculator on this site (while somewhat sleep-deprived due to a new puppy), this would give me 4.2 volumes of CO2 at 20 degrees and 4.89 volumes at 4 degrees C. Both figures are way more than suggested for an English ale.
Based on what I have read on the calculator page, I fear that the beer will be too heavily carbonated.

So, if I'm reading the calculator correctly and I bottle directly from the FV in the fridge (it has a tap which can take a bottling wand), then to achieve a target CO2 volume of 2.0, then I need to add just 1.1g of Dextrose sugar per 500ml bottle.
If I then leave the bottles to rise to ambient temperature (say 21 degrees C), then I will still end up with a CO2 volume of 2.0.

Please do correct me if I am wrong!

 

[An Ankoù]

Not sure about this dextrose solution- it depends on how much dextrose is present in said solution. Anyway, don't waste your money. Use ordinary table sugar. the yeast has the necessary enzymes to invert the sugar into its constituent monosaccharides and will do so at a fraction of the cost. You need about 4½ g per litre at 20C to end up with 2 volumes of carbon dioxide dissolved in the beer. I'd go for a tad more than that through personal preference. I like to pour a big head, which flattens the beer.

 

[terrym]

To be honest, I haven't used a calculator yet. I was going to add 7.5g of dextrose solution per 500ml (the recommendation on a video from Lovebrewing). Having looked at the calculator on this site (while somewhat sleep-deprived due to a new puppy), this would give me 4.2 volumes of CO2 at 20 degrees and 4.89 volumes at 4 degrees C. Both figures are way more than suggested for an English ale.
Based on what I have read on the calculator page, I fear that the beer will be too heavily carbonated.

So, if I'm reading the calculator correctly and I bottle directly from the FV in the fridge (it has a tap which can take a bottling wand), then to achieve a target CO2 volume of 2.0, then I need to add just 1.1g of Dextrose sugar per 500ml bottle.
If I then leave the bottles to rise to ambient temperature (say 21 degrees C), then I will still end up with a CO2 volume of 2.0.

Please do correct me if I am wrong!

If you are using the calculator do what @Drunkula has advised in post #6 i.e. use the highest temperature the beer achieved after it finished fermenting. So if you fermented at 20*C and then crash cooled use 20*C (not 4*C).
Otherwise do what @An Ankoù has said above i.e. use table sugar at the rate of 4.5g/litre, or one half level tsp sugar per 500ml bottle, or slightly more if you like a fizzier beer.

 

[foxy]

Brewers Friend calculator tries to calculate the amount of co2 drawn back into the fermenting wort, (colder the better I keep mine at -1 C) I have seen a sealed s/steel fermenter lid destroyed by the power of the sucking in back of shrinkage of the beer and the dissolving of the co2 back into the beer. But I just use the fermenting temperature 18 C to calculate the carbonation until someone can tell me how much co2 is present in the beer.

* Temperature of Beer used for computing dissolved CO2:
The beer you are about to package already contains some CO2 since it is a naturally occurring byproduct of fermentation. The amount is temperature dependent. The temperature to enter is usually the fermentation temperature of the beer, but might also be the current temperature of the beer. If the fermentation temperature and the current beer temperature are the same life is simple.

However, if the beer was cold crashed, or put through a diacetyl rest, or the temperature changed for some other reason... you will need to use your judgment to decide which temperature is most representative. During cold crashing, some of the CO2 in the head space will go back into the beer. If you cold crashed for a very long time this may represent a significant increase in dissolved CO2. There is a lot of online debate about this and the internet is thin on concrete answers backed by research. We are open to improving the calculator so please let us know of any sources that clarify this point.

 

[ExpatBrewer]

However, if the beer was cold crashed, or put through a diacetyl rest, or the temperature changed for some other reason... you will need to use your judgment to decide which temperature is most representative. During cold crashing, some of the CO2 in the head space will go back into the beer. If you cold crashed for a very long time this may represent a significant increase in dissolved CO2. There is a lot of online debate about this and the internet is thin on concrete answers backed by research. We are open to improving the calculator so please let us know of any sources that clarify this point.

I don't think any CO2 will be reabsorbed during CC unless the FV is 100% sealed tight.

 

[foxy]

I don't think any CO2 will be reabsorbed during CC unless the FV is 100% sealed tight.

It definitely does get absorbed with the drop in temperature, seal a vessel tight is asking for trouble.
Not sealed tight then air is drawn from the atmosphere.

 

[ExpatBrewer]

Yes. In a fully sealed situation the container can ultimately suffer the collapse illustrated in your photo due to a drop in pressure when the beer is cooled and also some CO2 may be reabsorbed as a consequence. However, in an unsealed container (FV) air is instead drawn in as the liquid cools and because that happens the CO2 won't get reabsorbed.