17 replies to this topic

[hz3gzy]

How do the pro's figure the percent of residual sugar? I see sometimes on the bottle, it says 1% residual surgar. How do the get the percentage? I am looking for a formula or a chart to show how many grams per Liter of residual sugar so I can test my wine.

[Howie]

I'm not sure what you're asking. Do you want to know how much sugar to add to a wine to get a desired level or do you already have a wine with residual sugar and are trying to figure out the percent?

[bzac]

1% residual sugar would be 1 gram per 100ml
or 10 grams per litre (1000ml)
7.5 grams per 750 ml bottle

gotta love the metric system

[hz3gzy]

I'm not sure what you're asking. Do you want to know how much sugar to add to a wine to get a desired level or do you already have a wine with residual sugar and are trying to figure out the percent?

The ladder!

[hz3gzy]

1% residual sugar would be 1 gram per 100ml
or 10 grams per litre (1000ml)
7.5 grams per 750 ml bottle

gotta love the metric system

Zac, how do you get the 1% value. I am trying to find out how much residual sugar I have left in a particular wine!

[Howie]

First of all, how was it fermented? Was it fermented to dry and then sugar added to sweeten? If so, and you know the volume and how much sugar was added, simply use Zac's method (you may have to convert to metric). If the wine did not ferment to dryness, then you can simply test with a brix hydrometer. Brix = % sugar, but it may be slightly higher, as a totally dry wine is a bit less than 0 brix.

[Bill Frazier]

"How do the pro's figure the percent of residual sugar?"

Here's a couple of ways to determine residual sugar;
Accuvin residual sugar tests ~ measures sugar between 0.01 to 0.20%
Clinitest tablets ~ measures sugar between 0 to 1%

These test kits are available from various winemaker supply stores.

[Crazy Run Ranch]

The wine labs/wineries use an enzymatic test to determine Glucose and Fructose residual in the wine. This uses a Spectrophotometer machine that is used to determine lots of other compounds in wine.

[hz3gzy]

First of all, how was it fermented? Was it fermented to dry and then sugar added to sweeten? If so, and you know the volume and how much sugar was added, simply use Zac's method (you may have to convert to metric). If the wine did not ferment to dryness, then you can simply test with a brix hydrometer. Brix = % sugar, but it may be slightly higher, as a totally dry wine is a bit less than 0 brix.

Howe, the wine fermented to dryness but out of curiosity I want to know how I can tell the % of residual sugar thats left. The posts below may get me where I want to go!
Thanks

[dagobob]

1% residual sugar would be 1 gram per 100ml
or 10 grams per litre (1000ml)
7.5 grams per 750 ml bottle

gotta love the metric system

So if I stabilize and add 1/2 cup of sugar which is about 3.75 grams to a gallon of finished wine (which BTW usually gets me to about 1.008) and I can get five 750 ml bottles out of a gallon, I should be at about .75% residual sugar; n'est ce pas?

[Howie]

So if I stabilize and add 1/2 cup of sugar which is about 3.75 grams to a gallon of finished wine (which BTW usually gets me to about 1.008) and I can get five 750 ml bottles out of a gallon, I should be at about .75% residual sugar; n'est ce pas?

Wrong - 1/2 cup of sugar is about 3.75 ounces.
EDIT: 3.75 ounces = 106 grams
2nd EDIT: My math give 28 g/L or 2.8% RS.

[dagobob]

Wrong - 1/2 cup of sugar is about 3.75 ounces.
EDIT: 3.75 ounces = 106 grams

d'oh you're right, my confusion, sorry 'bout that, and thanks for clarifying.

So continuing on, in my obtuse (and sometimes incorrect) logic, if I add 106 grams of sugar to 5 gals, I should have 2.8% sugar.
106 gms/~3750 ml = ~2.8%

[Howie]

d'oh you're right, my confusion, sorry 'bout that, and thanks for clarifying.

So continuing on, in my obtuse (and sometimes incorrect) logic, if I add 106 grams of sugar to 5 gals, I should have 2.8% sugar.
106 gms/~3750 ml = ~2.8%

Wrong again. That would give 2.8% in 1 gallon. In 5 gallons it would be .56%.
EDIT: - My rule of thumb is that 1 cup of sugar will raise 5 gallons 1 degree brix (actuall it's closer to 1.1).

[Luc Volders]

Howe, the wine fermented to dryness but out of curiosity I want to know how I can tell the % of residual sugar thats left. The posts below may get me where I want to go!
Thanks

Take 2 cups of wine, or enough wine to do a hydrometer
measurement with. So lets presume 2 cups.

Now boil this wine until half the volume has evaporated.
Fill up to the original volume with distilled water or
by lack of that tap water.
Take a hydrometer reading.

Boiling will have the alcohol evaporate.
Then filling up to the original volume makes
you able to measure residual sugar accurately.

Luc

[dagobob]

Wrong again. That would give 2.8% in 1 gallon. In 5 gallons it would be .56%.
EDIT: - My rule of thumb is that 1 cup of sugar will raise 5 gallons 1 degree brix (actuall it's closer to 1.1).

Damn, I meant to say 1 gal, not 5.
Thanks again Howie,
(maybe I should just keep quiet on this subject and return to my real job, engineering medical devices; double d'oh.)