The Lowdown on Lager Yeasts

[Evo]

So I've got myself a thermostat controlled brewing fridge and wanted to have another bash at a lager. Being more of an ale man and not having much success at lagers in the past, I thought I'd get some second (and third) opinions.

Neil (the owner of my HBS) has instructed me before and it went something like this - start your brew (can and kilo) at about 22 degrees. Pitch the yeast. Leave until fermentation starts (whatever your method of judging that may be ) then slowly reduce the temperature to the ideal brewing temp of the yeast (in my case Wyeast Danish lager - about 11 degrees).

My main question is how long should the drop in temperature take ? Also, what temperature should I lager at ideally ? And what about this diacetyl rest nonsense ? Geez, no wonder I stick to ales

Cheers
Evo

[Gough]

Evo,

This is a tough question with many varying methods. The problem with the method suggested by your HBS is that by the time your fridge has got your brew down to the desired fermentation temp the yeast will have taken off and half fermented your beer already. The higher temp leads to speedier fermentation and the production of non-lager like flavours. If you are using a proper lager yeast - especially if it is a liquid yeast designed to be brewed between 8-12 degrees you should try to get your brew down below 16 at the most before pitching. Pitch your starter at the same temp - match the temps. Once your fermentation takes off it generates heat. Your fridge will struggle to pull a fermentation that has taken off at 22 degrees down to 10-12 before the damage has been done.

I have used both methods. The pitch and brew cold method is fiddlier but gives better results. A diacetyl rest is also worthwhile. You've gone to the hassle of getting a temp controlled fridge - why not go the extra yard and get the temps down before pitching? Both methods can produce good beer, but getting your wort to temp or close to it before pitching is the best way in my opinion.

Good luck - and expect ten different suggestions before you make your mind up

Shawn.

[Guest]

Just to show you, my liquid lagar yeasts say don't cool down until you have a healthy fermentation at 70 deg.

I know this has been discussed before but can some one give me the low down on the diacetyl rest.

Thanks

Dogger

[Evo]

Well Gough, it seems one thing you were bang on with was the many differing opinions. I had a squiz at the White Labs website http://www.whitelabs.com/recipe.asp?Category=2 and they concur with your idea of starting the brew at the ideal brewing temp. Other sites suggest the method I wrote about originally.

As a happy medium, and since I will be using a 2 litre starter, what about kicking off the starter at a higher temp, slowly bringing it down, then pitching it into the wort at the correct temp (say 11 degrees) ? At least that way the yeast has a good chance of multiplying enough and hopefully since I'm chucking it into 18litres, shouldn't effect the flavour too much.

Oh, and the method mentioned on the White Labs site sounds good re the diacetyl rest as well. That is let your yeast brew for a while then bring the temp up for the diacetyl rest, then drop it down again slowly to lager. Thank god for my new thermostat I say. How would you do a lager without one ?

[Gough]

Evo,

Getting your starter going at a higher temp is a very good idea. Get those yeasties nice and fiery! Wyeast recommends 18-20 degrees or thereabouts for most of their lager starters. Bringing it down slowly to pitching temp is a good idea. Basically if you can get your wort and yeast starter to correct pitching temp for your lager yeast without infection (which is a hassle lets face it!) then that is the ideal pitching condition. If you can't, don't sweat it just do your best. Your beer will not spoil, just won't exhibit all the 'true' lager characteristics you may be hoping for. I've brewed lagers both ways and have recently converted to the 'everything cold' method. I have brewed nice beers using the pitch at 20 and drop quickly method, but not as nice. Because of the heat generated by fermentation the standard fridge will struggle to drop the temp quickly enough - that is why breweries invest in such expensive cooling gear to brew those crisp clean lagers.

Good luck with it. Now you have temp control you will brew good lagers. Just need to come up with a system that works for you.

Shawn.