Do you really need to take a vial of White Labs yeast out of the fridge 3-6 hours?

[linusstick]

3-6 hours before making a starter? If that's the case, I've never made a starter correctly.

 

[solavirtus]

I think they just don't want too much of a temp shock to the yeast. I would think that the main goal is just to have the yeast close to the same temp as the starter or wort it's going in.

 

[BrewForMe]

we all know what happens to "the boys" when we jump into the cold swimming pool...

 

[erkwist]

It's all about not shocking them, so its better if you do it, but don't worry about it to much.

 

[corncob]

I disagree.

There were a bunch of threads on here a year or so ago about "cold pitching." Many became convinced that the yeast are only "shocked" by sudden decreases in temperature. A sudden temperature increase at the time of introduction of huge amounts of malt sugar supposedly either made no difference or actually got them going faster.

I find it makes no difference and pretty much go straight from the fridge to the wort all the time now. Don't forget to shake them into suspension, though.

 

[ArcLight]

I disagree.

There were a bunch of threads on here a year or so ago about "cold pitching." Many became convinced that the yeast are only "shocked" by sudden decreases in temperature. A sudden temperature increase at the time of introduction of huge amounts of malt sugar supposedly either made no difference or actually got them going faster.

I find it makes no difference and pretty much go straight from the fridge to the wort all the time now. Don't forget to shake them into suspension, though.

Has this been scientifically proven?
It doesn't sound correct.
I don't think living things like rapid changes to their environment.
It may not kill them, but it may stress them.
I think at best it might not have much negative impact, but I don't see how it's good for the yeast.


Can you post a link or two showing scientific evidence backing this up?
If its true, it will save me several hours

 

[samc]

The well known and highly regarding Denny Conn is as I recall a proponent of pitching yeast cold. I tried it a few times with my starters and everything worked fine. I really had no way to do a side by side, but it works.

http://hbd.org/brewsandviews/messages/15516/19349.html?1070691958

http://www.danstaryeast.com/library/pitching-temperature-and-nutrients

 

[corncob]

Can you post a link or two showing scientific evidence backing this up?

Can you post a link or two showing scientific evidence that homebrew won't make you go blind?

In the end, there is no difference between scientific evidence and anecdotal evidence, other than tonnage.

 

[ArcLight]

In the end, there is no difference between scientific evidence and anecdotal evidence, other than tonnage.

Yes there is. Anecdoital evidence is not worth nearly as much. I don't say its not correct or worthless, just that it is suspect.

Its also hard to measure small differences in success rate.

You would have a hard time saying a .280 basesball hitter has a higher batting average than a .260 hitter if you didnt kepe track of hits and at bats.

Sam for beer making.
For example -
If two processes A and B give the same results 49 out of 50 times, but on the 20th A produces a ruined product. It would be extremely hard to identify that A is inferior because you would have mostly " I did A and it works great for me, never had a problem" type posts.



Samc,
Thank you very much for those links :rockin:

>>By Denny Conn Tuesday, December 02, 2003:
Nope, putting it in the fridge to drop the yeast out is the preferred method. Freezing will kill the yeast, but cooling won't. I don't even bother warming the yeast back up before pitching, after reading some recent study that implies that cold yeast will take off better. If I can just remember where I read it (maybe HBD), I'll post it.


> Danstar
If I had to take a guess it would be centered around the Trehalose content in the yeast cell. Trehalose seems to be an all around stress related factor. Almost immediately upon the cold storage of the yeast, trehalose begins to build up to help the yeast to adapt to its new environment. Upon pitching this stress factor assists the yeast to adapt to its new environment; warmer temperature and higher osmotic pressure. If the pitching yeast is allowed to warm up for any appreciable time before pitching the carbohydrate reserve, trehalose being one of them will be quickly used up as an energy source. The yeast would then take a longer time adapting to its new environment in the wort thus increasing the lag phase.

 

[SpanishCastleAle]

I always cold-pitch now and it does seem to take off quicker. Whether it's a pack/vial into a starter, decanted starter yeast into a carboy, or washed yeast into a carboy, I always cold-pitch. Other than a slightly quicker start I don't notice any other difference (other than it being a little easier to just pull it out and put it in). You don't want to go from warm yeast into cold wort but cold yeast into cool wort seems to work fine.

 

[corncob]

Scores of (internet) people brewing multiple batches seems like enough tonnage in the face of:

It doesn't sound correct.

That's why I tried it, several times, and found it to work for me--as best I can tell, with my admittedly small sample size. Before you take me to school on statistics, ask yourself how many batches it takes you to decide something does or doesn't work, like a recipe, for instance. The point I was trying to make is that data is data, whether collated by "scientists" or mere mortals.

 

[corncob]

I'm not trying to be a dick.

 

[TTB-J]

Scores of (internet) people brewing multiple batches seems like enough tonnage in the face of:

That's why I tried it, several times, and found it to work for me--as best I can tell, with my admittedly small sample size. Before you take me to school on statistics, ask yourself how many batches it takes you to decide something does or doesn't work, like a recipe, for instance. The point I was trying to make is that data is data, whether collated by "scientists" or mere mortals.

I think the point isn't so much whether you've replicated the results, but that some people want to know why the yeast would behave differently from a cold pitch state. Anecdotal evidence can be fine for purposes of feeling comfortable in getting to a certain result, but you generally need something more scientific to figure out the path between A and B.

 

[MNDan]

I've pitched cold for years - works every time.

 

[SpanishCastleAle]

Just curious, but what evidence (other than anecdotal) do you have that pitching at the same temp is best? Are you basing your belief on any scientific studies that prove this or just because several books said so?

 

[redcoat_or_rebel]

i don't a variation in temperature is the concern how big the variation is and what can the yeast withstand. If your yeast in in the fridge at say 50*F and you pitch that into 70*F wort, that's not a very big difference.

now if you pitched into 160*F wort, i would think it might kill the yeast. but a temp swing in general, in either direction, probably won't effect anything.