Do you follow the AHBS recipe instructions for lagering?

I buy a lot of recipe "kits" from AHBS - basically they just put all the ingredients together for you in the proper amounts, mix all the grain together in one bag, etc - and they always come with a handy little instruction sheet.

I noticed that for lagers - I'm doing a Mexican pilsner tomorrow - the fermentation instructions are always the same:

Once you see signs of fermentation, cool the primary to 50-55F, 1 degree per hour. After 10 days, raise the temp to 60-70F "to improve flavor" (I've always wondered what that meant, exactly). After moving beer to a secondary, cool the beer down to 40F, over 2 days, and leave for 3-4 weeks.

I'm just wondering, wouldn't different lager yeasts require slightly different temps and fermentation times? Is there a thread anywhere (I searched, couldn't find it) that would detail what happens at different temps and times for lagers?

This particular yeast is White Labs WLP940, if that helps.

I always ferment lagers at 50, but that is out of habit. For every yeast there is an optimal range, and you should read the description on the yeast company's website for that range.

Raising the temp after fermentation of a lager is referred to as a diacetyl rest, or d-rest. Diacetyl gives a butter slickness to the beer. Some lager yeasts produce more diacetyl than others, and it can also be a product of a warm start to the ferment. Either way, the yeast will eliminate it quickly at 65F. A couple of days is plenty for the d-rest.

rockout said:

I buy a lot of recipe "kits" from AHBS - basically they just put all the ingredients together for you in the proper amounts, mix all the grain together in one bag, etc - and they always come with a handy little instruction sheet.

I noticed that for lagers - I'm doing a Mexican pilsner tomorrow - the fermentation instructions are always the same:

Once you see signs of fermentation, cool the primary to 50-55F, 1 degree per hour. After 10 days, raise the temp to 60-70F "to improve flavor" (I've always wondered what that meant, exactly). After moving beer to a secondary, cool the beer down to 40F, over 2 days, and leave for 3-4 weeks.

I'm just wondering, wouldn't different lager yeasts require slightly different temps and fermentation times? Is there a thread anywhere (I searched, couldn't find it) that would detail what happens at different temps and times for lagers?

This particular yeast is White Labs WLP940, if that helps.

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Those are pretty good "generic" instructions and if you follow them, you'll be ok.

That said, I don't do that! The yeast manufacturer's tell you to pitch the yeast warm, then lower the temperature to get into the proper fermentation temperature range because you're really underpitching a lager with only one package of yeast.

I like to look at the actual yeast strain's guide, found on the yeast manufacturer's website: http://www.whitelabs.com/beer/strains_wlp940.html

And I always make a starter. Even White Labs says it's a good idea for a lager: "While a starter is not always necessary, White Labs recommends making a starter if the Original Gravity is over 1.060, if the yeast is past its "Best Before" date, if you are pitching lager yeast at temperatures below 65F, or if a faster start is desired."

A diacetyl rest, near the end of fermentation, is sometimes done for lagers to encourage the yeast to go back and digest their by-products like diacetyl. Raising the temperature 10 degrees when the fermentation is finishing up is one of the ways to encourage the yeast to do that. Some yeast produce less diacetyl than others, and a diacetyl rest isn't always necessary but some brewers do it as a matter of course with lagers.

Overall, those generic instructions aren't bad for general lager advice.

Most lagers ferment ideally in the 48-58 degF range. 50-55 degF is a good middle ground for almost every lager yeast strain out there except California lager yeast (which ferments at 58-68 degF). Be careful if you decide to ferment at 55 degF as some yeasts have a high end range of 56 degF, so you'd be cutting it a bit close. A general rule of thumb is that a longer, colder primary fermentation will result in a cleaner final product.

Hey thanks guys. @Yooper: I did make a starter, it's bubbling away at 70 degrees in my dining room right now. Do you chill the starter before pitching it? what temp do you chill the wort to before pitching? How long do you wait before you start lowering the temp to 50?

thanks for the white labs link, I never thought of looking there! excellent resource.

rockout said:

Hey thanks guys. @Yooper: I did make a starter, it's bubbling away at 70 degrees in my dining room right now. Do you chill the starter before pitching it? what temp do you chill the wort to before pitching? How long do you wait before you start lowering the temp to 50?

thanks for the white labs link, I never thought of looking there! excellent resource.

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I do chill the starter. I chill it a couple of days, because lager yeast are slower to fall out in the fridge than ale yeast. Then, I decant the spent wort and allow the yeast to rise up to 48 degrees. I chill my wort to 50 degrees, and then pitch the 48 degree yeast into 50 degree wort. I never pitch warm.

Just like with an ale, I don't pitch at 85 degrees, and cool to 65, I don't pitch a lager yeast 20 degrees above fermentation temperatures either. Some do, especially if they didn't make a big enough starter. But I feel that you get the best results either pitching at fermentation temperature, or just below fermentation temperature and allowing it to rise to the optimum temperature.

Pitching warm is a bandaid remedy for people who refuse to make a large starter. It's almost a perfect way of creating diacetyl that will never be fully consumed. Don't pitch until you get the wort down to at least 50.

YooperBrew said:

I do chill the starter. I chill it a couple of days, because lager yeast are slower to fall out in the fridge than ale yeast. Then, I decant the spent wort and allow the yeast to rise up to 48 degrees.

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Just so I'm clear - I'm currently letting the starter ferment at 70 degrees. Is that okay? And then once it's pretty much done, then throw it in the fridge?

Or should I slowly start cooling it now?

Thanks.

well, it might be a moot point now, as the airlock is slowing down....

rockout said:

Just so I'm clear - I'm currently letting the starter ferment at 70 degrees. Is that okay? And then once it's pretty much done, then throw it in the fridge?

Or should I slowly start cooling it now?

Thanks.

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Yes, I wait until it's completely finished and then stick it in the fridge. If it's a lager with a gravity higher than 1.050, I usually add some more fresh wort, to step it up, first. And let that ferment out. THEN I stick it in the fridge and decant it on brewday.

I don't use an airlock for my starter, just a piece of sanitized foil.

Well, this is a new question, but since it's directly related to this thread, I figured I'd just continue here:

I did make a starter and cooled it in the fridge for 3 days. After brewing on a 91 degree day outside, I was only successful in bringing my wort down to 57 degrees before giving up, and I decanted the starter. Problem was, I decanted so much that it became difficult to get all the yeast out of my Erlenmeyer flask and into the fermenter (i'll know next time to leave a little bit of liquid in there). So, I threw the primary fermenter into the fridge at 50 degrees, and on a whim, I recapped the flask and threw that in too.

The flask's airlock began to bubble again immediately, and realizing I had healthy yeast still in there, I sanitized some more DME, cooled it to 50, and threw it in there, for no other reason than to have a backup in case my main fermenter didn't start fermenting. That flask is still going.

This morning, about 36 hours after brewing, the airlock on my primary started bubbling.

My question now is, should I just throw in the yeast that's in the flask as well? I plan to wash yeast from the primary when I transfer to secondary anyway, so having the flask doesn't really do me any good just sitting there. Will it help the fermentation be more healthy if I throw in and mix with a sanitized spoon? ... thanks.

In the future, what you can do is take some of the wort from your fermenter and put it in the flask, shake it up, then pour it back in to the fermenter. That way you won't be pouring in any starter liquid, just your actual beer.

But, as far as I know, adding the leftover yeast in the flask now won't really help at all since the yeast has multiplied to make up the difference.