Hi
If you are going with kegs from most commercial brewers, they often recommend 36 to 38 F for storage temp. Indeed a good ale will have no taste at all at 36F. In most setups, the beer warms quite a bit between the keg and the glass on your table. More or less for a collar system:
Beer in keg at 36
Line at 38 (higher in freezer)
Shank at 44 (part in freezer)
Faucet at 70 (hanging out in the room)
Glass at 85 (room temp)
For a tower system with no fan:
Beer in keg at 36
Line at 38 to 85 (as it goes up the tower)
Shank at 85 (room temp)
Faucet at 85 (room temp)
Glass at 85 (room temp)
As the beer from the keg goes past all that stuff it tries to cool it down to 36. Beer sitting in the line is at what ever the line temp is.
The stuff the beer goes past tries to warm the beer up to what ever it's sitting at. They reach a bit of a compromise and the beer likely is around 45 when it fills up the glass. With something like the tower system the second pour will be at 45, who knows where the first pour will be.
Most (but not all) of us then take the glass somewhere and drink it. If it sits on the table for a minute or two, that's more warming.
To make it all a bit more complex, flavor depends a bit on how long its been at a given temperature. Ten seconds at 46 is not going to give you quite the same effect as a couple minutes. Then there's glass shape and degree of fill ...
You too can have fun with a digital thermometer and multiple glasses of beer. Just need one more data point to compete the graph ....
Bob
