Calculating "residual sugar content"?

[M38A1]

I visited a local winery this past weekend and spoke with the owner about their peach wines. He was willing to talk to me/confirm some things (held his yeast variety close to the vest) and talk about his sweetness benchmark. He referred to "...a residual sugar content of 6% is where he finishes".

I can wrap my head around Specific Gravity (SG) as sugar content before/during/after, but I don't know how to make a SG conversion to a percentage. For example, I know I run all my 6gal Dragons Blood batches down to dry at .990 from a starting SG of about 1.075, then bring sugar back in via simple syrup at 1cup/gallon. I think that puts me in the 1.010-1.015 range if I recall correctly.

So how does one calculate SG as a percentage of residual sugar?

...go easy please - my head hurts with all this stuff.

 

[Scooter68]

I gotcha on that number process. I just go to the flavor I like and stop a hair short. With peach it's bringing back the flavor that I go for. I don't have to have it sweet but the flavor and OH that aroma of a fresh glass of pure peach wine is intoxicating before the first sip even hits the palate.

BUT check these Three pages out. One talks about how a dry vs off- dry vs sweet wine compare in terms of grams/liter
then there is longer description and finally a calculator to help do the math.
If I understand the process correctly - You should be able to get to a 6% number by understanding that 0.2% residual sugar contains two grams of sugar in a liter of wine. So 6% / .2 = 30 or 3 grams per liter which the calcultor says is an SG of 1.012 (rounded up)

Chart - https://www.winecurmudgeon.com/residual-sugar-in-wine-with-charts-and-graphs/

Discussion - https://winemakermag.com/technique/501-measuring-residual-sugar-techniques

Calculator - http://www.musther.net/vinocalc.html#sgconversion

Hey and thanks for asking that question. I had never really addressed the categorization of wine with real hard numbers. I learned something by doing a little research.

Of course someone with a whole lot more experience will probably correct me and give you a better shortcut. (Hey I'm still learning)

 

[stickman]

6% sugar is quite a lot, it's actually 60g/liter.

 

[sour_grapes]

You can use Fermcalc to calculate how many g/l it would take to raise your SG from, say, 0.990 to 1.010. I think it takes something like 20 g/l to raise the SG by 0.010 points (but you can check my # on Fermcalc). So, it would take something like 40 g/l (AKA, 4% residual sugar) to raise your wine from 0.990 to 1.010.

 

[M38A1]

Thx for the info.....