Residual Sugar

[Brooothru]

I’ve been asked a brewing question that I’m embarrassed to say I can’t answer. My daughter has been on a special diet for the last several weeks to try to discover the source of a food allergy. Her doctor has instructed her to now eliminate wine and processed sugar to determine if these are triggers for allergic reactions.

I recently fermented a hard seltzer that had an OG of 1.045/11.3P and FG of 1.000/0.0P. The only ingredients were dextrose, mineral water, turbo yeast, nutrients and 2 oz of flavoring.
Her question to me was whether the complete attenuation indicated by FG 1.000/zero Plato indicates the absence of refined sugars.

My thinking is that there are other carbohydrates present, but simple sugars are not, based on the level of attenuation shown in the gravity readings.

Since I’m neither a chemist nor dietitian I’m at a loss to advise her. I know that wines are evaluated for residual sugars, and most generally they finish fermentation at gravities less than SG 1.000, although those sugars are fruit based rather than simple corn sugar. I believe the sugar being sought to eliminate is glucose/dextrose.

I’ll note that she and her family eat a well balanced diet rich in fresh fruits and vegetables, and avoid most processed foods and sugary, snacky fast foods or drinks. Wine, however, is something that both she and her husband enjoy regularly.

So I don’t really know what to tell her about sugar in the hard seltzer I made. Any insight would be greatly appreciated. TIA.

 

[lumpher]

Disclaimer: i'm not a chemist, just a winemaker who has done a.fair amount of research. Assumptions I work under: Even in a 1.00 drink, there are residual sugars, such as pentose, as much as 1 oz per gallon. At 1.000, it's considered semi-dry. Residual sugars have been debated for a long time, but there is a test you can get called the "Residual Sugar Test", made for diabetics, that will help you determine better. The 1 I know of is called the Clinitest Residual Sugar Test. I'm not an expert by any means; just providing some food for thought. Hopefully we have some chemists here who can provide good insight.

 

[Brooothru]

Disclaimer: i'm not a chemist, just a winemaker who has done a.fair amount of research. Assumptions I work under: Even in a 1.00 drink, there are residual sugars, such as pentose, as much as 1 oz per gallon. At 1.000, it's considered semi-dry. Residual sugars have been debated for a long time, but there is a test you can get called the "Residual Sugar Test", made for diabetics, that will help you determine better. The 1 I know of is called the Clinitest Residual Sugar Test. I'm not an expert by any means; just providing some food for thought. Hopefully we have some chemists here who can provide good insight.

That’s exactly the kind of information to get me headed in the right direction. Thanks.

 

[VikeMan]

If the FG only got down to 1.000, there's still some sugar. 100% real attenuation would measure as about 122% apparent attenuation, so "dry" for a 1.045 OG would be an FG of close to 0.990. I'm assuming that there's nothing in your 2 oz of flavoring adding significant gravity to the FG.

 

[Brooothru]

If the FG only got down to 1.000, there's still some sugar. 100% real attenuation would measure as about 122% apparent attenuation, so "dry" for a 1.045 OG would be an FG of close to 0.990. I'm assuming that there's nothing in your 2 oz of flavoring adding significant gravity to the FG.

Thanks VikeMan. That all makes perfect sense, and I'll inform my daughter to nix the seltzer in order to avoid all sugar.