Cold Pitching -- good read

[jsullivan02130]

The next thing you're going to tell me is that I could simply go down the street and "buy" beer. Easy? What the hell....

 

[smokinghole]

Well it seems to have taken off like a rocket. I had some bubble activity in the blow off jug after about two hours. The krauzen is building and will start blowing off in an hour or two is my guess.

 

[JKoravos]

I've been cold pitching since reading CJ's article last year. My lag times are very obviously shorter. I don't watch time it all that closely, but I'd say I notice activity within 2-6 hours. Like Denny, I pull my flask out of my fridge (~35F), decant the spent starter wort then pitch. Just one of those great tricks you learn over the years. I wouldn't do it any other way now.

 

[Ninoid]

I can confirm that this is a good technique and that I will continue with it.

 

[Ninoid]

After a dozen batch I did with cold pitch at three I had an off taste caused by a lot of esters. I have found that this happens after the second or third generation of washed yeast due to the yeast stress of pitch cold.

Before the cold pitch I had no such cases so I change my mind about that yeast pitch method and go back to the old way where I remove the washed yeast from the fridge for a few hours before it warms up to the temperature of the wort.

 

[Robert65]

Rinsing is far more harmful to yeast than any thermal shock. One of the worst practices perpetuated among homebrwers based on parroted, antiquated misinformation. Yeast should be stored under the beer it made until it is repitched. I know this is a zombie thread, but that's also a zombie practice.

 

[applescrap]

Thanks for resurrecting this zombie. I no chilled and it got a little cold so I pitched my yeast cold instead of letting it warm. I figured less stress since beer was cooler. Best fermentation ever. I pitch all my bread yeast cold, never an issue. So I have to try this.

 

[Ninoid]

Thanks for resurrecting this zombie. I no chilled and it got a little cold so I pitched my yeast cold instead of letting it warm. I figured less stress since beer was cooler. Best fermentation ever. I pitch all my bread yeast cold, never an issue. So I have to try this.

I also had a good fermentation, but my only logical explanation was why I got a beer full of esters, reading various texts, because of the yeast stress on the big temperature difference.

I'll try without a cold pitch so I'll see the results.

 

[Robert65]

I pitch from the fridge. I've regularly had my lager yeasts out to a good 25 generations or so before starting a fresh culture for no particular reason. Never an issue. If you believe yeast is showing signs of stress, temperature is probably pretty low on the list of suspects. I'd look at wort composition/ nutrients, oxygenation, yeast health, and pitching rates first. And the effective pitching rate could be lower than assumed if health of the yeast is compromised, and this effect will be cumulative over generations.

 

[Ninoid]

I pitch from the fridge. I've regularly had my lager yeasts out to a good 25 generations or so before starting a fresh culture for no particular reason. Never an issue. If you believe yeast is showing signs of stress, temperature is probably pretty low on the list of suspects. I'd look at wort composition/ nutrients, oxygenation, yeast health, and pitching rates first. And the effective pitching rate could be lower than assumed if health of the yeast is compromised, and this effect will be cumulative over generations.

You may be right, but I didn't have that effect until I started with a cold pitch. I did not change anything else in my procedure.

 

[Robert65]

Well that is sound troubleshooting procedure then!

 

[Denny]

I also had a good fermentation, but my only logical explanation was why I got a beer full of esters, reading various texts, because of the yeast stress on the big temperature difference.

I'll try without a cold pitch so I'll see the results.

Cold pitch is not the reason.

 

[applescrap]

Denny, you the man, love the show, the music. Just wanted to say that. Always heard something about "shocking" the yeast by pitching fridge temp yeast in warmer wort. Anyone know how this myth caught steam. I mean this is huge, isn't it? How many people concern themselves with matching wort and pitch temp, I was.

 

[Steveruch]

Denny, you the man, love the show, the music. Just wanted to say that. Always heard something about "shocking" the yeast by pitching fridge temp yeast in warmer wort. Anyone know how this myth caught steam. I mean this is huge, isn't it? How many people concern themselves with matching wort and pitch temp, I was.

I think "shocking" yeast has more to do with warm yeast being pitched into cold wort.

 

[Robert65]

A microbiologist (one is bound to jump in here at some point) will tell us that thermal shock in either direction is a real thing. They can observe it in their labs. But does it have any practical effect? I don't doubt that pitching warm yeast into much cooler wort could (temporarily) slow it down. But pitching yeast into relatively warmer wort should only help to wake it up. These seem to be the macro level effects that homebrewers see. And remember that the manufacturers' recommended rehydration practice for dry (active) yeast is to temper it from rehydration temperature to wort temperature with aliquots of wort, making 10°F drops at 15 minute intervals. Apparently even an instantaneous 10°F change isn't harmful, though a much greater one could be. At least that's the inference I draw.

 

[Ninoid]

My Cold Pitch practice is yeast at 5'C (41F) and wort at 20'C (68F).

 

[monkeymath]

At least in the linked article there isn't too much info to go on. I don't quite get why you would actively cool your starter - and hence slow down your yeast's metabolism - before pitching. But maybe this is just part of this weird "decanting" thing that people do?

The head of the yeast bank of Weihenstephan recommends pitching the starter at high kräusen, so that the yeasties are at their peak.

 

[Robert65]

I am pitching cold for one of two reasons.

I only make a "starter" (really stepped propagation) when starting with a fresh lab culture. In this case, the last stage is several liters of medium which I don't want to pitch into my beer, so it is chilled to settle the yeast and decanted.

Thereafter (most of the time) I am repitching, and as the yeast is harvested a few days before brewing, it has been stored in the refrigerator, and I take it out and directly pitch it.

In either case, the yeast will be at 37-39°F, and the wort at 48-50°F.

 

[cubalz]

This is exactly what Imperial yeast recommends on their packaging and I actually called Casey at Imperial to confirm a couple of years ago. I have done it this way when I use Imperial with no ill effects to my finished beer. I will say this: even to this day, it still does not "feel right" not warming up the yeast but some dogma is hard to shake...

 

[Broothru]

I think "shocking" yeast has more to do with warm yeast being pitched into cold wort.

^^^^^This

 

[Denny]

A microbiologist (one is bound to jump in here at some point) will tell us that thermal shock in either direction is a real thing. They can observe it in their labs. But does it have any practical effect? I don't doubt that pitching warm yeast into much cooler wort could (temporarily) slow it down. But pitching yeast into relatively warmer wort should only help to wake it up. These seem to be the macro level effects that homebrewers see. And remember that the manufacturers' recommended rehydration practice for dry (active) yeast is to temper it from rehydration temperature to wort temperature with aliquots of wort, making 10°F drops at 15 minute intervals. Apparently even an instantaneous 10°F change isn't harmful, though a much greater one could be. At least that's the inference I draw.

FWIW, dry yeast manufacturers no longer recommend rehydrating.

 

[Steveruch]

FWIW, dry yeast manufacturers no longer recommend rehydrating.

They finally caught up with me. I was way ahead of my time.!

 

[Ninoid]

After reading this post I started thinking in the other direction.

I mostly use US-05 for my beers and lately I have noticed that my attenuation is too high (about 85%). I did not change anything else in my procedure except to introduce a cold pitch with washed yeast. However, even when using yeast in the first generation (not washed) the attenuation is too high and it seems that I feel more esters in the beer than before. But with each next generation, esters become more pronounced.

Maybe something happened to that yeast in production or the yeast was not stored properly? I didn't look at the production date. Maybe he has expired?

 

[passedpawn]

FWIW, dry yeast manufacturers no longer recommend rehydrating.

I dunno about that. Just bought this... not sure where you get your info.

 

[beerfactory]

I haven't ever tried cold pitching, so I cannot comment. I have chilled starters/slurries in order to decant - but I haven't pitched the chilled.

I seem to remember that I have pitched when my wort was warm and that ale tasted differently when it came time to pour pints. I don't necessarily agree w/ that part of the link - I think it's worth chilling the beer to fermentation temp prior to pitching even though it can be a chore. I would chill overnight before I pitched on warm wort.

Q: I can't get my wort that cool with my immersion chiller. Does that mean I can't cold pitch?
A: No, you can still do it. Until recently, I used an immersion chiller and couldn't get my wort chilled to under fermentation temps. I've used the cold pitching technique in beers as warm as 79F, which I then continued to cool down with ice bottles strapped to the fermenter. Even with this continued cooling, I had lag times of only 2-4 hours.