Cold Crashing - please clarify some things for me

Before finding this forum, my impression of cold crashing was that it was done on a carboy to help clarify.

After reading on this forum, it seems like I was mistaken. I haven't heard it described here, but the context leads me to believe it is used for stopping fermentation on bottled drinks, or at least that this is an additional purpose for it.

I'll admit, that one doesn't really make sense to me because I didn't think it would get the temps cold enough to kill yeast, but that really seems to be what some people are talking about (correct me if I'm wrong).

So please clarify the uses of cold crashing for me. And one critical reason I want to know this: I want to make sparkling drinks such as cider or beer, but the whole process makes me a bit nervous. I'm reading the methods of pasteurization which seem somewhat ... imprecise, and dangerous. Other people interject cold crashing into this discussion as if it stops the fermentation and thus stops the building of carbonation. I just want to be sure I understand what is being discussed, and plan my "experiments" accordingly.

Cold crashing (at least here in home brewed beerland) is quickly lowering the temperature of beer to near freezing for 24-72 hours. The cold temperature and fast temp swing help to take dissolved solids out of solution - it helps to clarify the beer. It's basically the same process as lagering, although lagering is usually done for weeks or months, not days. Many people will add gelatin finings to the beer just before cold crashing to improve the process.

Pasteurization does not enter into the equation. If you want to kill yeasts and stop fermentation altogether, I believe sulfates are the preferred method.

if you want to make you bear clearer you could use a fining agent such as irish moss or cold crash.

i believe irish moss helps precipitate the protein out of the beer, which makes it clearer. irish moss and protein have opposite charges, so they bond. then the moss sinks to the bottom and you siphon the beer off the top.

cold crashing doesn't kill the yeast. ale yeast is top fermenting. if the yeast is still active and you are trying to speed up the process of clearing the beer out, you can cold crash and the active yeast will stop being active and sink to the bottom. then you siphon the beer off the top.

My understanding of cold crashing is to get yeast out of suspension to get a clear-er product, regardless of the container it is in. My understanding is that it does not necessarily kill the yeast so not all carbonation stops.

Thank you for the answers. So to be sure people understand what I'm asking, when I talk about pasteurization, I'm talking about posts like this:

https://www.homebrewtalk.com/f32/dishwasher-pasteurization-experiment-update-35873/

https://www.homebrewtalk.com/f32/easy-stove-top-pasteurizing-pics-193295/

The stove top pasteurization in the last link is referenced in some sweet recipes such as this one:

https://www.homebrewtalk.com/f81/5-day-sweet-country-cider-265986/


But I saw other posts along the way (and actually also in the stove-top pasteurizing post) where it sounded like cold crashing would stop fermentation and thus carbonation. That didn't sound right to me, but I'm a novice. It sounds like you're saying the same thing.

So then, if I understand correctly, if I want a sweeter drink, and don't want all the fermentables fermented out, and don't want bottle bombs, I really need to look at one of the pasteurization processes? Whereas with a dry brew, I can let all the fermentables ferment, then just add the priming sugar - careful to not add too much - and not get the bottle bombs. Am I summarizing that correctly?

another way to sweeten your brew or cider or whathaveyou is to use a sugar that beer yeasts can't eat. Maltose (also called "milk sugar") should be available at your LHBS.

Cold does not kill yeast, at least temperatures above freezing. Freezing will tend to kill yeast and other single-celled organisms because the formation of ice crystals in the cell will tend to burst the walls.

Irish moss is not a fining agent; it is a kettle coagulant. It has the same effect, but it is not used post-boil. You're thinking Isinglass.

Cold-crashing will stop bottle-conditioning, but once the bottle becomes warm the yeast will perk up and start all over again.

If you want to make cider and beer, put the whole pasteurization thing out of your head. Relax. It's not as hard as you're making it out to be. Just follow some basic instructions, find a tried-and-true recipe from a veteran denizen of HBT, and brew it. Don't worry about back-sweetening until you figure out you need to do it.

We have a saying, which we normally shorten to an acronym: Relax, Don't Worry, Have A Home Brew. RDWHAHB - literally, it means, "Quit obsessing. It's beer; nine times out of ten it'll figure itself out."

Don't obsess yourself into never starting! RDWHAHB and brew some beer!

Bob

P.S. Or cider. Same thing holds: RDWHAHBedCider.

I don't really care why, but these days I put my carboy(s) into a refrigerator to get them as cold as possible 2-7 days before I plan on kegging. When I don't my beer is less clear... so I do it. In the winter I put the carboy outside if the temps are likely to go below 40 f.

FWIW

Usually i dont cold crash, but i just kegged an oktoberfest, and its clear as day! well it was lagered for 5 months. i would like to cold crash some of my ales and bottle them, if you cold crash for 3 days, you will still have enough yeast to bottle carb right?

pablo1337 said:

My understanding of cold crashing is to get yeast out of suspension to get a clear-er product, regardless of the container it is in. My understanding is that it does not necessarily kill the yeast so not all carbonation stops.

Click to expand...

This is what I do with starters a day or so before brewing, so I can decant the beer and get most all of the yeast in the bottom..

muthafuggle said:

another way to sweeten your brew or cider or whathaveyou is to use a sugar that beer yeasts can't eat. Maltose (also called "milk sugar") should be available at your LHBS.

Click to expand...

.
Actually, beer would really really suck without maltose (malt sugar). You are thinking of lactose.

OP, if clear beer is what you want, you might try looking up gelatin fining