So after reviewing many of my materials on Trappist Ales, including a re-read of BLAM, The Great Beers of Belgium and Rajotte's Belgian Ale (among others), I hit upon an application of something I touched upon in a past writeup on bottle spunding.
Here's what we know:
1.) They all bottle condition with either a specific strain for bottling or their primary yeast.
2.) They all carbonate, on average, to > 3 vol/CO2.
3.) While most filter/centrifuge, they are not brilliantly clear.
One of the things that came up when Bryan used bottle spunding on a Helles was the amount of sediment that accumulated in the bottle. We are not talking a crazy amount (a little more than what you typically see in the Trappist examples) but definitely more than what you want in a Helles, which typically would be crystal clear after conditioning.
Bottling straight off the fermenter with extract left on a Trappist ale would be advantageous for a number of reasons:
1.) You will already have primary yeast in suspension with extract left, eliminating the need to add at bottling.
2.) Natural carbonation to the elevated levels seen in commercial examples.
3.) O2 protection from active yeast.
A forced fermentation test would be important in this application to ensure that you transfer into the packaging vessels at the appropriate time.
The math is pretty simple and we have it in the Low O2 spreadsheet under the Packaging section:
First you would identify a target carbonation level. In this example we'll use 3.2 vol/CO2.
Say we brew a Tripel with WY3787 following the Westmalle schedule. We ramp to 68 F after the first 3 days. Our residual carbonation would be:
Residual Carbonation = 3.0378 - (0.050062 * 68) + (0.00026555 * (68)2) = 0.861 vol/CO2
Kai wrote an article for Braukaiser a while back that had as a portion of it's contents the calculations for using residual extract to carbonate beer. They are as follows:
Each degree Plato of residual extract gives 2 vol/CO2, while each S.G. point of residual extract gives 0.51 vol/CO2.
To determine the carbonation required from residual extract:
Desired Carbonation - Residual Carbonation = 3.2 - 0.861 = 2.34 vol/CO2
Let's say our FFT gives an AA% of 85% and our Original Gravity for the beer was 1.064. We would expect a final gravity on the order of 1.009. So, our transfer gravity would be as follows:
((2.34/0.51)/1000)+1.009 = 1.0135 = 1.013
There are a few assumptions here:
1.) You have saved some thicker 11.2 or 16 oz. euro bottles.
2.) You assume that by bottling off the fermenter that you'll get an even distribution of yeast across all bottles.
Given the second assumption, it would be wise to undershoot your carbonation level for the first few times. Better to know that you have margin through empirical observation than to discover you don't by picking glass and sticky beer off the floor.
Topic: Bottle Spunding Trappist Ales (Read 10634 times)
