24 replies to this topic

[3rd party JKor]

This is why I love you guys. I first heard about cold pitching on this board, about a month ago. I've pitched the yeast for my last two batches straight out of the fridge. Both batches have taken off faster than any batch I've done before. They've both shown signs of activity within about 3 hours. Not having to remember to take the yeast out of the fridge is just one more hassle avoided on brew day.

[ncbeerbrewer]

+1

[Slainte]

Interesting. Haven't heard this. What is the benefit? Why does it work better?

[BarelyBrews]

Interesting. Haven't heard this. What is the benefit? Why does it work better?

I have been doing this for a couple of years, mostly because i try to re-use a slurry of yeasties if i have them on hand. Basically ,your introducing your yeast into a nice warm environment that is hopefully sterile and they can dominate.Going from forty degrees to sixty degrees(my wort target) really awakens the yeast.That is my un-scientific view.

Edited by Kegdude, 27 September 2009 - 03:13 AM.

[3rd party JKor]

Interesting. Haven't heard this. What is the benefit? Why does it work better?

Apparently, there is some literature out there that explains it, but I haven't seen it yet. There's a post in the FAQ section about it that CJ put together, although it doesn't have any detailed scientific explanation.FAQ

[ThroatwobblerMangrove]

I do it - it works.

[boo boo]

I do it - it works.

Yup, me too, and that's a fact jack.

[denny]

Interesting. Haven't heard this. What is the benefit? Why does it work better?

The basic theory is that yeast builds up nutrient reserves. If you warm the yeast before using it, it starts to consume those reserves before it goes into the wort. By pitching cooler yeast into warmer wort, the reserves aren't used until the yeast is in the wort.

[Iceman]

Yes, it works great. CJ turned me on to it years ago - haven't looked back. He's a wealth of knowledge on the subject.

[BrewerGeorge]

I do it on the rare occasion I use liquid. It works. I'm not sure why.

[consumptionjunction]

I really find Denny's theory compelling.This is just speculation, but based on what I've heard about "shocking" the yeast, and how it's really only a problem if you pitch warm yeast into a cooler liquid (and not the converse: cool yeast into a warm liquid), by pitching cool you would pretty much avoid shocking the yeast altogether.

[stellarbrew]

Whatever the reason, I know it works.

[Jimmy James]

The basic theory is that yeast builds up nutrient reserves. If you warm the yeast before using it, it starts to consume those reserves before it goes into the wort. By pitching cooler yeast into warmer wort, the reserves aren't used until the yeast is in the wort.

Makes sense. Plus the yeast are likely in an environment that doesn't support growth when they are in the tube/slurry. They are crowded and the wort is likely exhausted. Warm them up and they'd probably just wake up and then go dormant at temp. Pitching cold they'd wake up in a wort that encourages growth.

[maxieboy]

Took my cue from the practice of a microbrewery I used to work at. They took slurry from the bottom of cold crashed fermenters and pitched directly to fresh wort. The pros do it, why not us?

[denny]

Makes sense. Plus the yeast are likely in an environment that doesn't support growth when they are in the tube/slurry. They are crowded and the wort is likely exhausted. Warm them up and they'd probably just wake up and then go dormant at temp. Pitching cold they'd wake up in a wort that encourages growth.

Thanks, man....I was beginning to wonder if I'd really posted!

[Thirsty]

Uh, not working here. I pitched 3 week old slurry of wyeast 3522 Ardennes into 64 deg 18P wort. Took the mason jar out of the fridge, had about 1 inch of slurry, shook it all up to suspend, and pitched at 3pm yesterday. Todasy, still no signs. I have more to pitch if I need to, so I am not too worried- however I did not experience the famed faster than normal or rigorous fermentation this is supposed to give.

[3rd party JKor]

I don't know what you're normally pitching, but that seems like a little bit low of a pitch rate to me. I took a look at a mason jar, and I'd guess that 1" is approximately 150 mL. I've heard that harvested slurries lose about 25% viability/week, so you're probably under 50% viability. Let's be conservative and assume a 50% viability. Using Jamil's calculator, the recommendation is 250 mL of slurry for 5.5 gallons and 500 mL for 11 gallons.I don't know what your batch size is, you were probably too low on pitch rate which is extending your lag time.

[MakeMeHoppy]

I just got a stir plate and used my first started from it today. Based on this thread I left the starter in the fridge until time to pitch. I decanted more than half the beer of the starter until it started to look cloudy and then pitched everything else. I see activity after only 2 hours where in the past with rehydrated dry yeast it would take overnight.Cold pitching from now on!

[ThroatwobblerMangrove]

I just got a stir plate and used my first started from it today. Based on this thread I left the starter in the fridge until time to pitch. I decanted more than half the beer of the starter until it started to look cloudy and then pitched everything else. I see activity after only 2 hours where in the past with rehydrated dry yeast it would take overnight.Cold pitching from now on!

I don't know if comparing liquid yeast with a starter to dry yeast is really a fair comparison but a 2 hour lag time is pretty solid so I'd say keep doing what you are doing!

[beach]

I've making starters and cold pitching for about 9 months and I have very fast starts to my fermentations. I recently picked up a mini fridge, addded a temp controller, and put my stirplate inside. Now I have a temperature controlled fermentation chamber dedicated to yeast starters. After the starter ferments out, I turn off the stirplate and turn down the fridge. By the time I'm ready to pitch I just decant and serve. Beach