"Dry" wine tasting sweet

[BPL]

I am trying to wrap my brain around how and why a wine can taste sweet when fermented to dryness. Now for the back story...

Wine is a hobby for me, but fairly serious one. I make small batches, 1 gallon up to a max of 6 gallons at a time. I understand most of the science and wanting to understand more. For the past three years or so, most all of my wine has fermented to dryness, from a starting gravity of ~1.10/1.09 to a finished gravity of ~.995 to .990. I have exclusively used typical "yeast nutrient" (Urea/DAP) and achieved acceptable results-many times pretty good wines. None of these wines (roughly 50 to 60 batches) tasted naturally sweet. I assumed most all sugar was fermented.

Fast forward to 6 months ago... I started experimenting with organic nutrients. I read as much material as I could find about YAN, how nutrients work, dosages, etc. I started yeast using GoFerm, switched up (experimented) using Fermaid K / Fermaid O at AF and 1/3 sugar depletion, and monitoring SG. My starting/ending gravities were roughly the same: Starting gravity ~1.09 / Ending gravity ~.994 to .990. I have made about 8 batches of wine with organic nutrients, both fruit and kits. All 8 batches fermented down to .992 to .990. In each of the 8 batches, the wine has tasted a little on the sweet side and absolutely delicious! ...and yes, I checked my hydrometer against SG of water and even corrected for temperature. It's fine.

Why are the organic nutrients producing a sweeter finished wine when the SG is showing "dry" over the inorganic nutrients? What gives?

(I am new to this forum. This is my first post )

 

[Jovimaple]

Welcome to WMT!

I have no answers for your questions but will be watching this thread to see if others have an explanation.

 

[winemaker81]

I don't have a firm answer, but have a few guesses. First is you're not tasting sugar, you're tasting fruit. Something about the organic nutrients helped preserve the natural fruit flavor.

A second possibility is the glycerin level in the wine is higher than your previous wines. Temperature and nitrogen can increase the level (according to a couple of articles I found). Does the wine feel more viscous in the mouth? If so, glycerin seems to be the answer.

A third possibility is the nutrient contains a small amount of a non-fermentable sugar. It takes very little sugar to change a wine, and it may not be obvious from the SG.

Or it could be a combination.

 

[winemanden]

This is not really an answer. I have noticed in the past when I have made wines where I included Fructose that they always tasted just a bit sweet, and as winemaker 81 says, Glycerine does make your wine taste sweeter and smoother. I may be wrong, but I think most wine yeasts ferment Sucrose better than Fructose.

 

[CDrew]

There can also be residual sugars that are not fermentable, that add a sweet taste. Several years ago (2019) I made a Tempranillo that I had analyzed by Lodi Wine labs. And even though the SG showed that fermentation was well over, it still had 0.8g/L of "sugars". Reading up on that suggested it was likely Pentose (5 carbons) and not fermentable. That wine is stable and at this point tastes pretty good at 3 years old.

Glycerol which is a yeast byproduct also tastes sweet, and some yeast strains especially emphasize this. (See Bravo yeast from Renaissance and others).

 

[BPL]

I don't have a firm answer, but have a few guesses. First is you're not tasting sugar, you're tasting fruit. Something about the organic nutrients helped preserve the natural fruit flavor.

A second possibility is the glycerin level in the wine is higher than your previous wines. Temperature and nitrogen can increase the level (according to a couple of articles I found). Does the wine feel more viscous in the mouth? If so, glycerin seems to be the answer.

A third possibility is the nutrient contains a small amount of a non-fermentable sugar. It takes very little sugar to change a wine, and it may not be obvious from the SG.

Or it could be a combination.

Glycerin huh? Curious. I have not sensed a different mouth feel. If Glycerin, that would indicate it was created and/or already a part of one of the nutrients.

As far as the non-fermentable sugar in the nutrients, the amount of sweetness I am tasting would be about the same as mixing up a 1:1 sugar syrup/water and adding 1/8 cup/gallon. I guess I could taste the dry nutrients and see if they are sweet, right?

Thanks for the reply. Great answers!

 

[BPL]

This is not really an answer. I have noticed in the past when I have made wines where I included Fructose that they always tasted just a bit sweet, and as winemaker 81 says, Glycerine does make your wine taste sweeter and smoother. I may be wrong, but I think most wine yeasts ferment Sucrose better than Fructose.

Thank you! I found this article about gluc/fruc and fermentation. After reading the article (several times ) gave me the inspiration to ask the question on this forum. I have not tried adding glycerine to my wine "yet". https://www.lallemandwine.com/wp-co...rmentation-of-Fructose-in-winemaking-2013.pdf

 

[BPL]

There can also be residual sugars that are not fermentable, that add a sweet taste. Several years ago (2019) I made a Tempranillo that I had analyzed by Lodi Wine labs. And even though the SG showed that fermentation was well over, it still had 0.8g/L of "sugars". Reading up on that suggested it was likely Pentose (5 carbons) and not fermentable. That wine is stable and at this point tastes pretty good at 3 years old.

Glycerol which is a yeast byproduct also tastes sweet, and some yeast strains especially emphasize this. (See Bravo yeast from Renaissance and others).

Several replies about glycerine/glycerol being a possibility. I'll have to set up two batches that are identical except for the nutrients and give it try. Thanks for the response....something to think about.

 

[CDrew]

 

[BPL]

The video nailed it! Thank you so much.

 

[Rice_Guy]

* alcohol has a sweet taste! ,,, if I am formulating a zero alcohol beverage and a 11% alcohol beverage, it will take fewer grams of sugar to produce an equivalent sweetness taste panel rating
* I applaud using organic nutrients since they tend to be more efficient at fully fermenting the sugar. > more alcohol. There may be some effect on the type of residual sugar. Not all sugars are equally sweet, as for example fructose which is half of a table sugar molecule is more sweet than glucose (the other half of sucrose) aand the original sucrose molecule. What is interesting in fermentations is that fructose is also less preferentially fermented than glucose.
* sweetness is a balance. The combination of acid and tannic (bitter) need to be in balance with sugar(s) and alcohol. Tastes are a fuzzy science since tannin monomers can polymerize and reach a physical size where they don’t taste bitter and fall out of solution.

 

[Sailor323]

Not saying this is the case here but people often confuse fruitiness with sweetness.

 

[BPL]

Not saying this is the case here but people often confuse fruitiness with sweetness.

Thank you for the insight, but I definitely know the difference.