Author Topic: Pitching Temps for Ale Yeast quandary?  (Read 764 times)

Offline Lazy Ant Brewing

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Pitching Temps for Ale Yeast quandary?
« on: January 13, 2015, 02:30:18 PM »
I'm now doing all grain Ales and cooling about 6 gal of boiling wort with a 3/8 by 25 ft copper wort chiller. My cooling water comes from a local water tower and has varied (depending on season) from 76 F in Oct. to 56 F about Christmas -- I hadn't measured it prior to October.

It seems to take about 30 to 35 minutes to cool the wort to 80 F using an estimated 40 to 50 gals. of water. I could increase the water flow rate, but I've been trying is use a reasonable amount of water.

Should I transfer the wort to the fermenter at 80 F and pitch the yeast or should I try to get it closer to 70 F? The longer I have the copper chiller in it and use more time to cool it closer to 70 F the more I increase the risk of airborne contamination.

On the last batch after the wort had cooled to 80F, I added frozen water in eight 500 ml. bottles  (dunked in PBW solution) to provide additional cooling.  One of the caps came off, but when I bottled the brew after 20 days in the fermenter it tasted fine.

In John Palmer's "How to Brew" he says to rapidly cool the wort below 80 F, but then adds later that the closer you can get it to fermentation temp the better.

Any suggestions?

For those of you using copper immersion chillers how long does it take to cool your wort to 80 F? To 70 F?

Thanks in advance for your help.
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Offline Stevie

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Re: Pitching Temps for Ale Yeast quandary?
« Reply #1 on: January 13, 2015, 02:37:08 PM »
I get my wort down to about 80 with the same amount of water. After chilling, I whirlpool, and rack into the fermenter. The fermenter goes into my chest freezer to come the rest of the way down. A pump will certainly speed things up, but moving the chiller through the water column helps a great deal.

I've heard mixed info on flow rate. Some have said that an increased flow rate doesn't help as the transfer of heat from the wort to the water does not reach it's capacity. I run mine at the lowest point I can with the hose bib vacuum breaker not spewing water out the side, about a half to three-quarter turn. Takes about 15-20 minutes to knock-down 6 gallons, and an addition 10 to knock-down 12 gallons.

Offline klickitat jim

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Re: Pitching Temps for Ale Yeast quandary?
« Reply #2 on: January 13, 2015, 02:42:49 PM »
I have a 60' 1/2" IC with recirculation via pump. My ground water is 45 in winter and about 50 in summer. With wirlpool recirculation I drop half way to equilibrium every minute or so. Meaning the lower it goes the slower it goes. My last batch was a lager and it took about 15 minutes to get to 60, at wich point I killed the whirlpool so it would start settling. After 15 minutes of settling it was at 48 for pitching temp.

So, if you can, double the length of your IC. Whirlpool during chilling, which can be done by stiring though a pump is tge easy way. Also allows you to cover the pot with foil to keep critters out, which is the answer to your contamination concern.

I am a big fan of pitching at or below your target fermentation temp.
« Last Edit: January 13, 2015, 02:44:38 PM by klickitat jim »

Offline morticaixavier

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Re: Pitching Temps for Ale Yeast quandary?
« Reply #3 on: January 13, 2015, 02:43:39 PM »
I have a couple of specific suggestions but first a general one: relax, don't worry, have a homebrew.

40-50 gallons to get 6 down to 80 seems really really high. are you stirring or otherwise moving your wort while chilling? if not you should be able to cut your chill time in half just with that.

Getting it below 80 quickly is great but if you can't do it so it goes. get it as cool as you are willing to waste water on and then put it in the fermenter and let your fridge or the cool night air get it the rest of the way down to pitching temp.

Don't pitch the yeast into the wort until it's at or below 65* if that takes 12 hours so be it.

Airborne contamination while chilling is unlikely, contamination while chilling in the fermenter is unlikely. as you learned when your bottle of chilling ice opened in the wort, contamination is harder than we think.

I live in northern california and my ground water in summer is... pleasant for bathing let's say. I chill 11 gallon batches to ~90 in 20-30 minutes with a 50" copper IC. I run the water full bore because as long as the water is coming out hot, it's getting all the heat it can out. when the output water starts to feel cooler I stir. when stirring doesn't make the output water feel much warmer I call it quits, pull the ic, whirlpool, let settle and run off into the fermenters. those go into the fridge and I aerate and pitch in the morning.

I use about 35 gallons of water for 11 gallons of wort this way.
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Offline duboman

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Re: Pitching Temps for Ale Yeast quandary?
« Reply #4 on: January 13, 2015, 02:53:12 PM »
I use a CFC for chilling and in Chicago our water is about 50 in the winter and 75 in the summer. I run my water at about half throttle as I've found running it full on does nothing anything faster. My runoff water is used for cleaning and also runs into a 50 gallon rain barrel that I then use to water my garden.

In the winter it takes about 15 minutes to bring 6.5 gallons to 60 degrees, the summer about 30 minutes to 75 as I throttle back the kettle flow to get a better chill. In the summer I'll then place the primary in the fermentation chamber to chill down further and it takes an hour or two, then I'll aerate and pitch.

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Offline epic1856

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Re: Pitching Temps for Ale Yeast quandary?
« Reply #5 on: January 13, 2015, 04:45:12 PM »
Similar tap water temp where I live in Southern California. Here is what I do. I use an immersion chiller as well.

Run immersion chiller from tap and get it down to 100 degrees. Takes about 10-15 minutes. I use about 20 gallons of water for this. Then I connect my immersion chiller to a sump pump. Pump is in a bucket of ice water and recirculate. 7 lbs of of ice gets it down to about 70, but if I use 14 lbs, it goes to low 60s. Also throughout the chilling I am stirring the wort every 5 minutes or so, the more you stir the faster it will cool down.

Offline brewinhard

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Re: Pitching Temps for Ale Yeast quandary?
« Reply #6 on: January 18, 2015, 11:48:11 PM »
I have taken upwards of 1.5-2hrs to chill a batch of lager down to 46-48F in early June before.  That was with an ice bath recirculated with an immersion chiller.  I brew and cool inside my garage (not outside). I have never had an airborne infection from this providing a big strong healthy pitch and proper aeration of wort.  The yeast simply outcompete any nasties that might have made their way into the kettle.