Residual Sugar %

[bmd2k1]

How do you determine the RS% in ur cider?

Stopped in Tandem Ciders near Suttons Bay, MI this past weekend - amazing ciders as always....and they list residual sugar %

Their current cider offerings is below.

 

[Maylar]

Prolly by final specific gravity?

 

[bmd2k1]

Prolly by final specific gravity?

How'd u convert an SG reading to an RS% ?

 

[Maylar]

Start with 1.050, end with 1.004, RS = 8%.

 

[dmtaylor]

Per BJCP Cider guidelines:

 

[bmd2k1]

Start with 1.050, end with 1.004, RS = 8%.

What's the equation to determine that?

 

[dmtaylor]

What's the equation to determine that?

Probably 4 / 50 = 0.08. But that's only apparent attenuation, not residual sugar, since typical FG in cider with champagne yeast is 0.994-ish, and since alcohol messes up the calcs.

 

[Maylar]

Yeah that was just a guess on my part.

 

[NateBodnar]

Looks like 1 Brix = 1% is a good estimate, from googling a bunch and comparing the standards posted for SG levels to brix. As stated above alcohol would change this a little but it should get you close enough of an estimate right?

 

[bmd2k1]

Looks like 1 Brix = 1% is a good estimate, from googling a bunch and comparing the standards posted for SG levels to brix. As stated above alcohol would change this a little but it should get you close enough of an estimate right?

Yeah...I was just curious based on seeing them posted by Tandem and looking for a ballpark for my ciders

 

[MarkKF]

So if my hydrometer (triple scale) says 1 Brix when done it means 1% residual sugar regardless if I started at 1.046 or 1.054?

 

[RPh_Guy]

Residual sugar (RS):
The sugar percentage by weight in the fermented cider.
This has nothing to do with the OG.

I'll show you online calculators to calculate RS two ways....

Without considering alcohol:
http://www.musther.net/vinocalc.html
Enter the FG. It gives you the g/L of sugar. Divide by 10 to get the percentage (grams per 100mL).
Example: FG 1.019 is 49.2g/L = 4.92% RS
1.019 is 4.8 Brix, so that's a relatively close estimate of RS without accounting for the alcohol density.

With alcohol adjustment:
http://fermcalc.com/FermCalcJS.html
Alcohol > Hydrometer SG Drop
Enter the OG and FG, adjusting for temp if needed. It gives you the final sugar percentage.
Example: OG 1.050, FG 1.019 = 6.3% RS ("true brix")

 

[MarkKF]

Residual sugar (RS):
The sugar percentage by weight in the fermented cider.
This has nothing to do with the OG.

Example: OG 1.050, FG 1.019 = 6.3% RS ("true brix")

Thanks that makes sense. I thought it was a percentage of the original sugar not a percentage of the weight.

 

[bmd2k1]

Residual sugar (RS):
The sugar percentage by weight in the fermented cider.
This has nothing to do with the OG.

I'll show you online calculators to calculate RS two ways....

Without considering alcohol:
http://www.musther.net/vinocalc.html
Enter the FG. It gives you the g/L of sugar. Divide by 10 to get the percentage (grams per 100mL).
Example: FG 1.019 is 49.2g/L = 4.92% RS
1.019 is 4.8 Brix, so that's a relatively close estimate of RS without accounting for the alcohol density.

With alcohol adjustment:
http://fermcalc.com/FermCalcJS.html
Alcohol > Hydrometer SG Drop
Enter the OG and FG, adjusting for temp if needed. It gives you the final sugar percentage.
Example: OG 1.050, FG 1.019 = 6.3% RS ("true brix")

Thanks!

 

[bmd2k1]

Found this simple calculation for SG to Brix/residual sugar%

 

[RPh_Guy]

Found this simple calculation for SG to Brix/residual sugar%

View attachment 603288

That's only true with no alcohol present. See my calculations above.

 

[bmd2k1]

That's only true with no alcohol present. See my calculations above.

Thanks...my bad. Was looking for the equation behind that web calculator - oh well - will just use the calculator. Interesting there's a bunch of different "takes" on the ABV -- wonder which one the majority of producers use?

 

[RPh_Guy]

Thanks...my bad. Was looking for the equation behind that web calculator - oh well - will just use the calculator. Interesting there's a bunch of different "takes" on the ABV -- wonder which one the majority of producers use?

It's javascript (calculations are done client side), so you could find the equation by digging around in the page source if you really want. I'd look but I'm not at a computer, sorry.

It's good to remember that most things we measure/calculate are just "good enough" estimates ... without access to $$$$$$ scientific equipment.

There are compounds in the wine contributing to the density besides sugar and alcohol. If you could measure and correct for the gravity points contributed by acidity you'd have an even better estimation of RS.
Maybe that explains why the BJCP estimates for RS are a bit lower than what I calculated. I used FG 1.019 in my example because that's the suggested cutoff between "medium-sweet" and "sweet", which they're saying is only approximately 4.0% RS.

I don't know how commercial wineries handle ABV calculations. I'm guessing they don't put too much thought into in because it's not government regulated.