prankster1590
Well-Known Member
- Joined
- Sep 24, 2019
- Messages
- 58
- Reaction score
- 11
I need an estimation of the average gravity during the boil when using Tinseth. I have a certain way of calculating things that seem to be a little different than the way most people seem to be calculating things, so I have often different numbers. which is strange since there is only one truth and that is the number of the actual beer.
If I for example calculate an IBU of 23 and a certain homebrewerfriend calculator calculates 21, than im a little bit worried because the calculation should be the same, so it should give the same number. I think the difference is in the calculation for the average boil gravity.
This is how I would calculate it:
I want a 20 L of wort in the Fermenter with a gravity of 1,0477.
I tap of 20 liters wort from 22 liters of wort leaving trub and hops debri. Thus I need 22 L of wort with a gravity of 1,0477
22 L * 47,7 gravity points = 1049,4 points in total
I always keep in mind 4% shrinkage because of cooling down. So 22 L/0,96 = 22,917 L. This would be, for me, the post boil volume. And this is what maybe causes the difference in my calculation compared to calculations of others. Should I take this number as post boil volume or should I use the cooled down volume of 22 L as post boil volume?
So at 22,917 the boiling is stopped altough not cooled down. The evaporation rate is about 7%/60 minutes. So If I end with 22,917 L and I have been boiling for 60 minutes than I should have started with 22,917/0,93 = 24,642 L of wort containing a total of 1049,4 gravity points. That has a gravity of: 1049,4 total points/24,642 L = 42,6 point = 1,0426
*So if i take the cooled down post boil volume of 22 L.
1049,4 points / 22 L = 47,7 = 1.0477 (Which also the Final gravity). Than the average boil volume would be
(42,6 points (24,642 L) + 47,7 points (22 L))/2 = 45,15 =1,0452
*If I take 22,917 as post boil temperature than the average boil gravity would be
1049,4 points / 22,917 L= 1.0458
(42,6 points (24,642 L) + 45,8 points (22,917 L))/2 = 1,0442 as average boil gravity
So the question is. Which average boil gravity or post boil volume should i use in Tinseth?
The one with an postboil volume of 22 L and an average boil gravity of 1,0452 or the one with a post boil volume of 22,917 L with an average boil gravity of 1,0442.
If I for example calculate an IBU of 23 and a certain homebrewerfriend calculator calculates 21, than im a little bit worried because the calculation should be the same, so it should give the same number. I think the difference is in the calculation for the average boil gravity.
This is how I would calculate it:
I want a 20 L of wort in the Fermenter with a gravity of 1,0477.
I tap of 20 liters wort from 22 liters of wort leaving trub and hops debri. Thus I need 22 L of wort with a gravity of 1,0477
22 L * 47,7 gravity points = 1049,4 points in total
I always keep in mind 4% shrinkage because of cooling down. So 22 L/0,96 = 22,917 L. This would be, for me, the post boil volume. And this is what maybe causes the difference in my calculation compared to calculations of others. Should I take this number as post boil volume or should I use the cooled down volume of 22 L as post boil volume?
So at 22,917 the boiling is stopped altough not cooled down. The evaporation rate is about 7%/60 minutes. So If I end with 22,917 L and I have been boiling for 60 minutes than I should have started with 22,917/0,93 = 24,642 L of wort containing a total of 1049,4 gravity points. That has a gravity of: 1049,4 total points/24,642 L = 42,6 point = 1,0426
*So if i take the cooled down post boil volume of 22 L.
1049,4 points / 22 L = 47,7 = 1.0477 (Which also the Final gravity). Than the average boil volume would be
(42,6 points (24,642 L) + 47,7 points (22 L))/2 = 45,15 =1,0452
*If I take 22,917 as post boil temperature than the average boil gravity would be
1049,4 points / 22,917 L= 1.0458
(42,6 points (24,642 L) + 45,8 points (22,917 L))/2 = 1,0442 as average boil gravity
So the question is. Which average boil gravity or post boil volume should i use in Tinseth?
The one with an postboil volume of 22 L and an average boil gravity of 1,0452 or the one with a post boil volume of 22,917 L with an average boil gravity of 1,0442.
Last edited: