I was just thinking, if you top up a demijohn after racking off, so that you still have enough for six bottles and then take the FG, it will mess up the ABV calculation! I suppose I should check the SG before topping up with water (or syrup).
Topping up after taking OG
- Thread starter kelper
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The Original Gravity (OG) should be taken after the addition of any dilutant or adjunct and before the addition of yeast, yeast nutrient etc for fermentation.
The Final Gravity (FG) should be taken after any addition of water but before the addition of carbonation sugar and bottling. (*)
Hope this helps.
(*)
Personally, I add 0.5% ABV to a brew to accommodate the addition of carbonation sugar.
The Final Gravity (FG) should be taken after any addition of water but before the addition of carbonation sugar and bottling. (*)
Hope this helps.
(*)
Personally, I add 0.5% ABV to a brew to accommodate the addition of carbonation sugar.
I agree. My bad.
However, in the situation you propose there would be two OG's and two FG's!
1. OG and FG for Fermentation. This will give you a starting ABV and OG for the finished wine.
2. OG (finished wine) and FG after the addition of water. This will give you a smaller ABV.
Deducting the smaller ABV from the original ABV should give you the ABV of the finished wine.
Example:
Original Wine OG 1.095 to FG 1.010 = ABV 11.16%
adding water to drop SG of original wine gives
OG 1.010 FG 1.004 = ABV 0.79%
ABV of diluted wine = 11.16 - 0.79 = Final ABV of 10.37%
I just hope that the calculations now make sense.
Topping up won't alter tha ABV much.
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