Homebrewers Association | AHA Forum

General Category => General Homebrew Discussion => Topic started by: Richard on March 22, 2019, 02:03:25 AM

Title: Cold crash - how cold is cold enough?
Post by: Richard on March 22, 2019, 02:03:25 AM
I have been testing a new cooling system and although I am pleased with its performance overall, I am a bit disappointed in its lowest achievable temperature. My old system could cool down to 34 F, but the new one can only get to 36 so far. Is that good enough? I can work on getting it lower, but it would be quite an effort. I usually keep the beer at the low temperature for 3-4 days before packaging.
Title: Re: Cold crash - how cold is cold enough?
Post by: Robert on March 22, 2019, 02:22:00 AM
Most yeast drops pretty quickly anywhere below 40°F.  Really there's not much difference between 34°F and 36°F.  Both are cold.  I wouldn't worry. 
Title: Re: Cold crash - how cold is cold enough?
Post by: ynotbrusum on March 22, 2019, 11:22:54 AM
Also make sure your thermometer is reading correctly - you could be colder or warmer than you think!  I would measure with an accurate probe in a glass of water for best results.  Cheers!
Title: Re: Cold crash - how cold is cold enough?
Post by: Richard on March 22, 2019, 03:30:08 PM
Also make sure your thermometer is reading correctly - you could be colder or warmer than you think!  I would measure with an accurate probe in a glass of water for best results.  Cheers!

Accuracy is not a problem. I have a PT100 RTD probe that is accurate to better than 0.5 degree F checked across the entire range from freezing to boiling.
Title: Re: Cold crash - how cold is cold enough?
Post by: ynotbrusum on March 22, 2019, 05:02:10 PM
Sounds like you have it dialed in - my point was that relying on the thermostat of the cooling chamber (refrigerator or freezer), as some folks do, for temperature settings can be somewhat unreliable.  By all means, proceed with what you have, it is way more than appropriate and you have confirmed with full temp range readings.

Cheers.
Title: Re: Cold crash - how cold is cold enough?
Post by: Bob357 on March 23, 2019, 08:46:29 AM
I crash at 40F. It takes a bit longer, but still able to go grain to glass in 14 days for most beers.
Title: Re: Cold crash - how cold is cold enough?
Post by: majorvices on March 23, 2019, 12:43:44 PM
Under 38 has been best for my experience and certain fining agents like BioFine need to be close to 32 to really work well.
Title: Re: Cold crash - how cold is cold enough?
Post by: MattyAHA on March 23, 2019, 05:30:22 PM
i cold crash @32F-34F serve at 38F
Title: Re: Cold crash - how cold is cold enough?
Post by: Richard on March 23, 2019, 08:23:26 PM
i cold crash @32F-34F serve at 38F

Wow, that is a pretty cold serving temperature. If I remember correctly in England they serve their local beers at something like 50F, which is called "cellar temperature" or "cold", and they serve American beers closer to 40F, which is called "ice cold". As with wine, the temperature affects the volatility of aroma compounds, and too low a temperature will reduce the aroma and flavor you get from the beverage.

My cooling system will produce lower temperatures, but the water in the heat exchange block began to freeze and clog the hoses with ice when the beer was at 35.5. I could go lower if I use propylene glycol to lower the freezing point of the cooling liquid, but I don't want to do that unless it is absolutely necessary.
Title: Re: Cold crash - how cold is cold enough?
Post by: MattyAHA on March 23, 2019, 09:58:34 PM
i cold crash @32F-34F serve at 38F

Wow, that is a pretty cold serving temperature. If I remember correctly in England they serve their local beers at something like 50F, which is called "cellar temperature" or "cold", and they serve American beers closer to 40F, which is called "ice cold". As with wine, the temperature affects the volatility of aroma compounds, and too low a temperature will reduce the aroma and flavor you get from the beverage.

My cooling system will produce lower temperatures, but the water in the heat exchange block began to freeze and clog the hoses with ice when the beer was at 35.5. I could go lower if I use propylene glycol to lower the freezing point of the cooling liquid, but I don't want to do that unless it is absolutely necessary.
i can let the beer warm up if need be in the glass, i prefer cold beer for the styles i brew plus the colder the beer is stored the fresher it stays
Title: Re: Cold crash - how cold is cold enough?
Post by: Robert on March 23, 2019, 10:31:26 PM
^^^^
My preferred serving temperature is 45°F; I keep my keezer set at 40°F, on the assumption that the beer will warm up a good 5°F when poured into the glass/mug and allowed to sit for a minute.  Same basic idea.
Title: Re: Cold crash - how cold is cold enough?
Post by: Richard on March 24, 2019, 03:56:05 AM
OK, then I would say that the 38 - 40 F temperature is the STORAGE temperature, not the serving temperature. US refrigerators can't be set to temperatures above 42 F because that is the max temperature for food safety. After various attempts to force mine to regulate higher I have given up. I store the beer at a low temperature but generally let it warm up a bit (how much depends on the style) before I serve it. I don't really measure the final temperature in the glass, but now I might start doing that just for fun!
Title: Re: Cold crash - how cold is cold enough?
Post by: Robert on March 24, 2019, 11:21:55 AM


I don't really measure the final temperature in the glass, but now I might start doing that just for fun!
It's fun once.  You know, just for reference.  After that it may be pathological.   ;)
Title: Re: Cold crash - how cold is cold enough?
Post by: hopfenundmalz on March 24, 2019, 02:01:04 PM
If you keeping kegs at 38F, one trick is to rinse your glass with hot water when making it beer clean.
Title: Re: Cold crash - how cold is cold enough?
Post by: MattyAHA on March 24, 2019, 05:03:39 PM
OK, then I would say that the 38 - 40 F temperature is the STORAGE temperature, not the serving temperature. US refrigerators can't be set to temperatures above 42 F because that is the max temperature for food safety. After various attempts to force mine to regulate higher I have given up. I store the beer at a low temperature but generally let it warm up a bit (how much depends on the style) before I serve it. I don't really measure the final temperature in the glass, but now I might start doing that just for fun!
i use a chest freezer with a bunch of damp rid so i can get my beer as cold as i prefer, my dry stout i prefer warmer then my G pils but still colder then people say you should serve, i have measured the temps in the glass but IMO it is not that important i just use my senses, there is recommendations for temps according to style i dont believe any of it its all up to what the drinker wants
Title: Re: Cold crash - how cold is cold enough?
Post by: Robert on March 24, 2019, 05:20:02 PM







 i use a chest freezer with a bunch of damp rid so i can get my beer as cold as i prefer,

Same here

its all up to what the drinker wants

I'm American, I even like my British ales cold and fizzy
Title: Re: Cold crash - how cold is cold enough?
Post by: MattyAHA on March 24, 2019, 06:39:59 PM







 i use a chest freezer with a bunch of damp rid so i can get my beer as cold as i prefer,

Same here

its all up to what the drinker wants

I'm American, I even like my British ales cold and fizzy
yup exactly
Title: Re: Cold crash - how cold is cold enough?
Post by: Richard on March 24, 2019, 09:53:02 PM
I'm American, I even like my British ales cold and fizzy

Yeah, my British ales are quite Americanized, too. I like them stronger and with more foam than the Brits do.

That reminds me of my last visit to the north of England in 2016. I was dismayed to see that all the pubs carried American beers in addition to local ales and cask ales. One evening I was at the bar waiting for a refill and a guy asked for a Coors. The bartender pulled the handle and just got a hiss and a spit or two of foam from an empty keg. The customer then asked for a Bud Light, and the bartender again got just a dying sigh from an empty keg. I turned to the guy next to me and asked "I wonder what his third choice is when his first two were Coors and Bud Light?" The answer was Foster's.