To what degree is flavor (s) expressed in a lager when the fermentation temperature is varied?
Not a styles debate or question.
At what point in varying temperature will the flavors, desired or not, be noticeable in a lager beer? Comparing say a primary fermentation of 44F to 50F for example.
4 Responses
EtOHRx
08 Feb 2010
Character Study
08 Feb 2010
I should think that it is noticeable, to the trained beerocrat, at just 2 or 3 degrees difference. This being especially true for the temperature as it approaches the low to mid 50’s. Although, I do not know the flavor difference from 44 to 50 degrees yeast do produce more fruity esters at the higher temperatures.
Construct
08 Feb 2010
Warmer temps. may leave your Pils with a high level of Diacetyl.
http://en.wikipedia.org/wiki/Diacetyl
http://beerme.com/diacetyl.php
Beer
08 Feb 2010
Chemically they can be measured as increasing constantly with temperature increases. But the final product will only be judge by the flavor humans can detect which may be more sensitive but less direct. I say it is a the point where fruity esters begin to be produced. This is likely in the mid to upper 50’s F for a lager yeast. The diacetyl issue raised is a good point as well.
It is not a matter of degree but perception. Assuming that all things are equivalent during the brewing process such as splitting the brew into or three batches after pitching the yeast, the variables would be too numerous to consider. But let us consider this very thing. We then ferment the beers at three separate temperatures. Each will have a varying flavor spread according to the yeast characteristics.
As stated some yeast produce more fruity flavors than another strain. A single strain will produce different flavors according to the environmental conditions it is subjected too. So the flavor and aroma of the lagers will vary according to both the yeast strain and the temperature of the fermentation.
To what "degree" you want to know flavors will be expressed according to temperature differences.
Not much and not much different from what has been stated before me (above). The main concern on flavor from temperature variation is diacetyl diacetyl (butter-butterscotch) and acedealdehyde (green apple).
This wiki is actually a quite good article on the subject of major concern for a clean fresh flavored lager.
http://www.homebrewtalk.com/wiki/index.php/Fermenting_Lagers#Primary_Fermentation