DB Backsweeting Question

[winesleeper]

Current SG is .992. Would like a final SG of 1.012. I have 6 gallons of DB. Will this be correct? Take 6 cups of wine out of the carboy. Make a simple syrup using 5 cups of sugar with 2.5 cups of water. Add simple syrup to fill the carboy. Also, could I use 2.5 cups of wine, in place of the water, to make the simple syrup?

 

[bkisel]

Either process will work but I don't know if the 2.5 will be what you need to get to 1.012. Make the syrup and maybe add half to see where it brings you. Continue adding to get the SG up higher or stop when there. Guess you could always make more syrup ifin the first amount wasn't enough.

 

[dangerdave]

I think he's using 5 cups of sugar, Bill.

I always say "sweeten to taste". Wines are different from eachother. A 1.012 with one type of wine may not find balance in another. If this is your first batch of DB, start with a few cups of sugar and work your way to where you want it. You may find that 1.012 is too sweet, or you may like it with a little more. Stop just short of your goal, as the tartness will receed over time.

Good luck, winesleeper, and thanks for trying the recipe!

 

[bkisel]

Yep, I understood 5 cups of sugar to 2.5 cups water or wine. So far the most I've used in back sweetening is ~2 cups of sugar to just take the edge off a dry wine and to help it be a bit more of an early drinker. [So far 9 kits. Will likely be trying DB next.]

Is there a rule of thumb for how much sugar to raise SG a certain amount?

 

[winesleeper]

My 5 cups of sugar with 2.5 cups of water did make 6 cups of simple syrup. Poured in 4 cups of simple syrup and the SG was at 1.004. This was not sweet enough for my better half. So I added 2 more cups of simple syrup and the SG was at 1.008. Based on comments about the change in tartness with time, we decide to stop at 1.008. Have about a half gallon extra that I left dry that I have started drinking myself. Thanks dangerdave for the great recipe.

 

[Arne]

Go to http://web2.airmail.net/sgross/fermcalc/fermcalc_applet.html and you should be able to calculate how much sugar you are going to need. Works for me, although I usually use less than it calls for, then measure the s.g. and add a bit more til I get it where I want it. Arne.

 

[jamesngalveston]

I think dave said it best....
Stop just short of your goal, as the tartness will receed over time...and has on every batch that I have made...If you get it to where its sweet before bottling, it will be too sweet after a month....

 

[beggarsu]

Current SG is .992. Would like a final SG of 1.012. I have 6 gallons of DB. Will this be correct? Take 6 cups of wine out of the carboy. Make a simple syrup using 5 cups of sugar with 2.5 cups of water. Add simple syrup to fill the carboy. Also, could I use 2.5 cups of wine, in place of the water, to make the simple syrup?

After a wine is finished fermenting (dry) and stabilized with sulphide and sorbate the SG is longer any use in determining the ABV and is inaccurate.
I have tested this.
What is completely accurate is a simple mathematical calculation,
It is the new volume that determines the new ABV.
When I have time I will write this equation in general form but for now it can be found here as an example.
The math is faultless - the SG which didn't compare to the math wsas proved to be inaccurate - that is because th enew SG after adding an F-PAck or sugar is not derived from fermenting and also the new liquid added is a different type - SG is no longer valid unless arrived at through fermentation.

oow. nor liq



http://www.winemakingtalk.com/forum...fandel-aka-rockin-raspberry-44149/#post502141

Here it is:
The final volume was 22.50 litres (carboy) - 1.4 liters = 21.1 litres (1.4 taken out as reserve) at 13.09 ABV (which was determined by starting and ending SG's)
Total alcohol content of that 21.1 litres = (13.09 * 21.1) divide by 100 = 2.76199 litres pure alcohol in the batch.

New volume after add 1.4 F-pack = 22.5 litres
New ABV = (2.76199/22.5) * 100 = 12.27 ABV



---
Taking the SG after F-PAck was 1.010 - this gives 10.87 ABV by online calculator which obviously is incorrect as the previous math is correct.

Therefor SG method after F-Pack is inaccurate (probably because it is a different liquid - it's just not the same thing any more relative to the starting must.

Therefore final ABV = 12.27 not 13.09 as just using the starting and ending SG of the fermentation.
...
Which sounds about right - a small difference , not quite one percent for diluting with 1.4 volume of another liquid.

The above calculation can be used to calculate final ABV for any kind of back-sweetening as in adding volume (cups of sugar of simple syrup for instance).