times for primary? secondary? and diactyl rest?

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pcolson

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How long can i leave my lager in the primary? and also the secondary? and dolonger times change the taste or anything about the beer? also i have read a little about diactyl rest? what does the diactyl rest do for my lager? how do i accomplish this?

Patrick
 
A Diacetyl rest is accomplished by pulling the fermenter out of your fridge and letting it sit at room temps for 24 hours. It is done because a lager is not supposed to have a diacetyl taste at all to it. As far as leaving the beer in the primary and secondary, lagers are normally left in primary for at least 14 days or more, and in secondary for months.
 
awesome thank you... at what point do i take it out of the cooler and let it sit at room temp? and after the 24 hours is up do i transfer it to the secondary or put the primary back in the cooler?
 
I've only done two lagers, but both times I left it in the primary for 14 days, pulled it out for 24 hours, then racked it to my secondary for the lagering phase. They both turned out pretty well, imo. :)
 
Thank you for the help i will be doing the d rest next friday then then racking to the secondary ill let ya know how it goes
 
Lagers are not quite as simple as all that. You can't just follow a time table on every beer and be OK like you can with most ales. Some yeast strains don't produce any diacetyl so a d-rest isn't necessary, others do. In any case, a d-rest won't do you any good if you wait until primary fermentation is done. Some yeast produce diacetyl during fermentation (ales and lagers), ales are already warm enough, so before fermentation peters out, the yeast clean up after themselves and no special attention is needed by the brewer.

For a lager, the yeast can't clean up the diacetyl at lager fermentation temps, so you must raise it to 65-70 degrees for a period of 24 hours or so, near the end of fermentation. If you wait too long, the yeast will be asleep, and won't do jack to clean up after themselves, too early and you will get esters and fusel alcohols formed. When the yeast is about 75-80% of the way to final gravity is when you want to do a d-rest. You can kind of judge this after some experience by watching the krausen and airlock, but you really need a hydrometer. When you have reached near terminal gravity, let the temp of the beer self rise to around 65 and hold it there for a day. After the day, slowly (about 5 degrees per day) bring it back down to lager temps. I usually transfer to secondary when I have gotten back to my fermentation temps, and by then fermentation has completed. It also helps clear out some of the yeast waiting till it's cool again to transfer. Go to secondary, drop to lager temps, and wait.
 
Awesome i will test when i get home to see where its at! and what temp should i keep my secondary in? i heard between 36-42
 
You can actually go right down to 32, beer has alcohol in it, so it need to be under 32 to freeze. The closer to freezing, the more the particulates and tannins will settle out, but 10 degrees warmer and you can lager a little faster. According to John Palmer, at freezing you should lager for a couple months, and you can go up to almost 50 and get done lagering in a couple weeks, but it may have some haze and not be quite as crisp.
 
When the yeast is about 75-80% of the way to final gravity is when you want to do a d-rest. When you have reached near terminal gravity, let the temp of the beer self rise to around 65 and hold it there for a day. After the day, slowly (about 5 degrees per day) bring it back down to lager temps.

Why slowly? Yeast already did their job, I think, they can floculate as fast as they want...
 
You don't want the yeast to go into shock and flocculate immediately. If this happened, then they wouldn't be able to condition the beer, making lagering pointless. You may have heard of "cold crashing", that is what you would be doing if you didn't go down slowly, which is for the purpose of clearing out the remaining yeast before kegging. The yeast still isn't completely done either, they're still cleaning up by-products, and you want the yeast to be able to finish cleaning up after themselves.
 
You don't want the yeast to go into shock and flocculate immediately. If this happened, then they wouldn't be able to condition the beer, making lagering pointless. You may have heard of "cold crashing"

Yes, and I heard some commercial breweries do it on purpose, to get clearer beer.
My understanding was: conditioning are mainly chemical reactions, yeast do the cleaning job during long primary and diacetyl reast.
 
when i pitched my yeast i left it at room temp for 6 hours till i have air lock activity then put it in the fridge... doesnt it cool it extremely slow anyway?
 
When they are in active primary fermentation, it is going to be pretty hard to make them flocculate out, and it does take a little while for 5 gallons of wort to cool down especially when there is an exothermic reaction taking place within the vessel.

I know the white labs vial says to pitch at room temp, but Chris White from White Labs says that if you pitch at fermentation temps, you will have a cleaner fermentation, again because of the reduced stress on the yeast. Pitching at room temp just helps reduce lag time, but if you have a good active starter (and you should, especially for all lagers), that won't be a problem. You don't have to do it slowly, but your beer will benefit.
 
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