Found out today that you can use a nylon hop bag over the racking came to reduce hop sediment into beer. Does anyone do this? Seems to be a better and quicker alternative to cold crashing.
Cold crashing is about making the beer clear of yeast and possibly insoluble protein. I often cold crash and use a nylon bag during racking to filter out hop particles.
This will not fix any of the yeast/haze issues, as they are far smaller then the holes in the hop bag. Using certain finings at room temp like polyclear(i believe) is the only option compared to cold crashing or filtering.
Jeff
Not a cold crash fan for a few reasons:
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Rapid temperature swings (up or down) are stressful on the yeast. May help them floc, but it also may cause them to release stress compounds. Even if flavor profile is unaffected, stress reduces vitality of the slurry for the next pitch.
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Cold crashing in your fermentor increases exposure/uptake of oxygen. Cooling liquid increases gas solubility and reduces total volume (increases headspace in the vessel). In an atomspheric environment, the headspace gained by reducing the volume is filled with air, and the oxygen in that air is more soluble at the lower temperature.
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Cold crashing before bottling means (at least) longer carbonation times and (most likely) stunning the bottling yeast.
#2 is not an issue in a purged keg on CO2, but you still can stress yeast left in suspension with a rapid temp drop.
I’m sure there are tons of great homebrewers that make award winning beers by cold crashing in the fermentor. Its just not something I do. Its definitely not necessary.
The purpose of cold crashing is not to clear the beer. It’s to set chill haze so that filtration/finings/time can remove it. Completely different objective from keeping particulates out (which just requires keeping the siphon off the trub, IME).
Not to mention essentially all commercial brewers.
Would you say their is less stress on the yeast if the cold crashing happened over a 7 day period. For instance I took my beer from 65 deg. fermentation to 34 deg. cold crash over 7 days. So I took temperatures down each day in the morning 4.4 deg. I am bottling today and will let you know how this beer which is a kristallweizen comes out.
Have you personally tried cold crashing and experienced any of those negatives?
According to that other thread, Niva from White Labs says cold crash as fast as you can without freezing the yeast
IME time works pretty well to clear a beer, as does gelatin.
However, as Sean points out you need cold to set the chill haze if you want to remove it.
I don’t know that you need to crash to set the chill haze. You can probably cool the beer at whatever pace you like.
But you can’t remove chill haze at room temp.
I can see Kyle’s point if cold crashing in the fermenter, but we mostly all cold crash in the keg if we keg the beer at ferm temp then put it in the kegerator. I don’t think it makes any difference either way. I think yeast are resilient enough that cold crashing doesn’t hurt them or make them release off flavors while cold crashing.
I like to keg my beer at fermentation temperature, let crash in the kegerator for a day, then add finings.
Then it wouldn’t exactly be ‘crashing’ would it? 
Its not a necessary step but it does help in a few ways. I mainly cold crash to get the beer cold and ready for kegging. Only doing so after the beer is ready and is a finished product for the most part. Time at cold telps after kegging is where I see most of my clarity from.
The combo of Cold crashing and gelatin has done wonders for clarity in my beers with no noticeable negative flavor impact. In certain beers I have noticed an improvement of flavor. I personally attribute that to the decrease in suspended yeast. Admittedly that’s just an assumption and could be related to some other change in my process, however. At a minimum I’ve only personally noticed positive effects.
I currently overbuild and harvest from my starter, so no worries about impacts from cold crashing. I never noticed any issues with yeast viability when I was harvesting from primary, however.
Agreed. This ^^^^^
+2. The vast majority of beers just taste better with the yeast out of suspension. I like crashing + gelatin for most beers.
Just realized this was a zombie thread.
Great timing this morning for me. I almost forgot to start my cold crash. It totally reminded me to go out to my garage and turn the temp down on my ferm chamber.
Gotta love it.
Denny - I’ve experienced #1 with English, lager, and Kolsch ale strains. The lager was the last straw. It wasn’t side-by-side, but it was the same recipe, brewing and fermentation schedule. Cold crashed beer was noticeably inferior.
I think I’ve also experienced it in a saison, but I couldn’t rule out other variables.
#2 is more a physical than a sensory observation. When all of the liquid in the airlock gets sucked into the carboy after cooling, there is obviously air introduced.
Overall - NOT cold crashing has NOT negatively affected my beer or process. OTOH, a slow rise in temp to finish fermentation followed by a slow steady ramp down to maturation temp has, IMO, made huge improvements. Other than a short gain in time, I don’t see any benefits in a cold crash vs slowly cooling.
Not to mention cold crash lowers temp gradually , not like going from room temp to 32F in an hour. Once yeast are done, crash away and either keg or gelatin and keg works for me.
I have a theory that cold crashing to 30F its good for my chest freezer. Being able to run throttle wide open overnight once a month, seems to me, is a good thing. Its also been very good to my beer.
Could be right.