Collaborative brew with Steve Kirchner.
We needed to chill the wort as much as possible, preferably somewhere around 44F so we could pitch the yeast and slowly raise the fermentation temperature to 50F. The plan was to use the immersion chiller w/ the whirlpool attachment in the brew kettle at flame out and use ground water (assumed to be somewhere between 65-75F) as the source. This would chill the wort enough to get a cold break and the whirlpool would create a cone of the break material in the BK that would hopefully keep it out of the plate chiller and fermentation vessel.
The next step would be to send the wort through the plate chiller that was using prechilled water (using the first immersion chiller in an ice bath) then through another post-chilling copper coil in an ice bath before finally ending up in the Sanke keg fermentor.
This is where things went sideways. When I removed the immersion chiller (IC) from the BK, I placed it into the bucket we were going to use for the pre-chilling ice bath. This IC also has a piece of copper tubing that is situated inside the copper coils and curved to allow pumped wort to flow over the chilling coils. The idea is that it not only exposes more wort to the chilled surface areas, but it creates a whirlpool action that helps with break material. Wort is pumped out of the valve at the bottom of the BK, through a pump and then back into tubing that's connected to the piece of copper adjacent to the IC.
The problem was that before removing the IC, I forgot to close the valve on the BK and gravity took over. By the time I removed the hop bags and went to check the final volume of the wort in the site glass, The wort had flowed out of the BK and into some random, unsanitized bucket we were going to use for the pre-chill ice bath. We lost about 3-4 gallons of chilled (66F) wort. We decided to dump it and go forward with our 9 gallons left in the BK.
After transfer losses, we are probably going to end up yielding about 7.5 to 8 gallons of finished beer.
20110619 - Swapped blowoff tube for airlock.
20110621 - Fermentation has slowed down. Raised temp to 60F for diacetyl rest.
20110626 - Fermentation has slowed. Slowly lowering temp back down to 52F
20110627 - Temp is now 52F.
20110702 - Racked into secondary glass carboys. Looks like about 4 - 4.5 gallons in each. SG is around 1.018, so it can probably go a little longer before needing to be lagered.
20110905 - Started carbonating the keg w/ my portion (about 4+ gallons).
20110908 - Took a sample to the meeting and there is a strong diacetyl character.
20110914 - After some research about ways to eliminate diacetyl, found this link on Brew Your Own:
Basically, if it's not an infection (which I doubt, but could be a possibility), the problem is a result of doing the diacetyl rest *after* most of the yeast has flocced out and there isn't enough to clean up the diacetyl left behind during primary fermentation phase. There is a good possibility this is what happened.
20110915 - The mini-batch has already reached high krausen, so pitched it straight into the keg which has a blowoff connected to the gas in port. Plan is to keep it at 60F for about two weeks, then lager it again.
20110916 - Checked this morning and the blow off tube is gently bubbling every 5-10 secs. Hopefully, this doesn't dry it out too much.
20110927 - Took a sample to compare with the untreated version in Steve's keg. The untreated version exhibits the same diacetyl buttery aroma and almost 'greasy' aftertaste. The 'scrubbed' version with the repitched yeast doesn't show any signs of the previous diacetyl and has a good, clean malt flavor. I think it worked! Steve will get another smack pack of the Wyeast 2206 and we'll do the same thing to his keg.
20110928 - Moved the keg into the big fermentation fridge and will start cooling it down to re-lager. 2 degrees per day until we get to 50-ish.
|Enter desired final yield (volume):|
|10.00 pounds||38.5% of grist|
|8.00 pounds||30.8% of grist|
|6.00 pounds||23.1% of grist|
|2.00 pounds||7.7% of grist|
Total Grain Weight (Water Amounts
|100% of grist|
|2||Whirlfloc @ 15 minutes|
|10 tsp||Yeast Nutrient @ 15 minutes|
Hallertauer Mittlefruh3.40% Pellets @ 60 minutes
Hallertauer Mittlefruh3.40% Pellets @ 20 minutes
|5.75 ounces||Total Hop Weight||19.6 AAUs|
|Total Boil Time:||90 minutes|
My Equipment [cegolf]
|Batch Size:||10.00 gallons||Boil Volume:||12.55 gallons|
|Evaporation Rate:||10.0% per hour||Mash Tun Dead Space:||0.8 gallons|
|Efficiency:||70%||Mash Tun Weight:||9.00 pounds|
|Hop Utilization:||100%||Mash Tun Volume:||10.00 gallons|
|Loss:||1.5 gallons||Mash Tun Specific Heat:||0.30 Cal/gram per °C|
Two Step Temperature Mash, Light Bodied Beer
|Grain Temperature:||72°F||Tun Temperature:||72°F|
Mash with a direct heat source to maintain temperature.
|1||Protein Rest||Infusion||30 min.||122°F||
Add 100% of mash water at 129° F / 54° C
Heat to 150° F / 65.5°C over 15 minutes
|3||Mash Out||Temperature||10 min.||168°F||
Heat to 168° F / 75° C for at least 10 minutes
|Primary:||7 days @ 50° F|
|Secondary:||0 days @ 50° F|
|Tertiary:||0 days @ ° F|
|Age:||28 days @ 36° F|