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Lager Fermentation

Lager Method. 

I found various procedures on the net this one has a good reputation and can complete the fermentation in 10-14days if you use plenty of yeast, however I also checked it with major yeast suppliers.  

Tasty’s Fermentation Procedure. (From his post on HomebrewTalk.)

I pitch and oxygenate at 55F /12.8°C and hold until the gravity drops 50% of the way to terminal gravity (For example, if my OG is 1.052 and I expect to finish at about 1.010, then a drop of .021 gravity points would be 50%.)

I then raise the fermentation temperature by 3 degrees to 58F/14.5°C and hold until the gravity drops 75% of the way to terminal gravity.  

I then raise the fermentation temperature by about 2 degrees to 62F/ 18°C and hold until the gravity drops 90% of the way to terminal gravity.

I then raise the fermentation temperature by about 2 degrees to 66F/19°C and hold until I reach terminal gravity.

With this method, 75% of the fermentation takes place at 58F/14.5°C or below, 90% at 62F/18°  or below. 

Comments on Tasty’s method.

Many thanks for your mail and your interest in Fermentis products, for a lager fermentation it is OK. You could also start fermentation at 12 ° C during the first 2 days and then leave it up to 14 ° C until the end of fermentation. The end of fermentation will be slower than you could have with your profile but it will be easier to manage. Best regards Jean-Jacques Bourdalle.

I don’t see a reason why this would not work with our Brewferm strain. The temperature increases are not that high (and not abrupt, I suppose) and the yeast has time to adapt itself to this; so, no problem. Best regards, Dirk  

Diacetyl Rest.

Some lager yeasts produce a chemical that tastes like butterscotch if you’re using one when the fermentation is 80 to 90% complete let the temperature rise to 18⁰C until the fermentation ends. For example if the expected final gravity (FG) is 1.010 and the initial gravity was 1.050 then 0.05-0.01 = 0.04 x 0.9 = 0.036 so 90% complete would be an SG of 1.014.

Lagering Procedure.

Lagering involves storing or conditioning the fermented beer at low temperature for a prolonged period. Some people recommend ramping down from fermentation temperature to lagering temperature I’ve not found it worthwhile. 
According to C Bamford’s book “Tap into the Art and Science of Brewing” a few days at -1ºc is the equivalent of several weeks at 5ºc. one notable UK brewer works on the basis of 1 day at -1ºc equating to 1 week at 2 - 5ºc.  
When I’m lagering a beer I usually give it 10 to 14 days at -1ºc which is quite long enough for any lager I’m likely to make.

Both Lallemand and Fermentis have published data showing lager fermentations complete in under 7 days BUT you need to pitch a LOT of yeast.

Fermentis W34/70   from a Fermentins Publication .

Key conclusions

Our study has demonstrated the constant neutral character of SafLager W-34/70 over different fermentation conditions, including higher temperatures. This yeast remains very robust and stable over many different conditions. The most important point for the brewers is this: SafLager W-34/70 can ensure both a faster and neutral fermentation profile at higher temperatures. The same neutral beer in less time in the fermentation tank.

Lallemand Diamond   Yeast. From their data sheet .

  • In Lallemand’s Standard Conditions Wort at 12°C (54°F) Diamond yeast exhibits:
  • Vigorous fermentation that can be completed in 5 days
  • High attenuation and High flocculation Neutral flavor and aroma, typical of traditional lagers

The optimal temperature range for Diamond yeast when producing traditional styles is 10°C(50°F) to 15°C(59°F) Lag phase, total fermentation time, attenuation and flavor are dependent on pitch rate, yeast handling, fermentation temperature and nutritional quality of the wort. 

In both cases you need to be pitching about 2g/l of dry yeast to obtaind the very rapid fermentation.