Concord wine problems

[winemaker81]

Concord grapes have a flavor that I enjoy so I have absolutely no experience with wine making using these grapes. But I wonder, and no one seems to have spoken to this point. The fact that neither of the yeasts used were able to pull this wine any closer to brut dryness than 1.006 suggests to me that there may be compounds in the juice that affect the density of the liquid but which are not themselves fermentable sugars. Is that possible?

It's certainly possible, especially as the source fruit is a concentrate.

However, as has been noted, yeast does its own thing. I've had half a dozen batches made from something other than fresh fruit fail to ferment to below 1.000, and a few fresh fruit that also failed. In these situations, I never figured out what went wrong -- assuming anything went wrong. Your point that the SG reading is due to something other than fermentable sugar is a possibility.

@rbqricchi, at this point, I don't see that you did anything wrong. Stuff happens. On the plus side, you like the result so far, so it's really a win. Give it a few months, bottle, and enjoy!

 

[rbqricchi]

I wondered that myself, but then realized that the wine is slightly sweet, which suggests that the remaining gravity points are at least partly because of residual sugar.

 

[David Violante]

I’ve made concord for several years now, but I need to look at my notes to give some accuracy. Aside from the first few “learning experiences” most have been pretty dry if I remember correctly. I’ll be back…

 

[David Violante]

So, "pretty dry" on my part is quite subjective as I haven't actually tested for residual sweetness. Also, I'm re-reading the conversation about the possibility of SG points accounting for non-fermented sugars and other compounds in the finished wine. Definitely possible. I'll take the OG in clear must right before pitching yeast and after it has had time to mix thoroughly. I'll check SG along the way to be sure to add nutrients at the right time, and use activity, SG and temperature drop to determine when to move to a sealable container (with a silicone breathable bung). I'll usually let the wine sit and clear, finish MLF if desired, rack off the gross lees, and then somewhere down the road check FG in a clear wine that has had time to settle and degas. Well, that's my current process. It sure didn't start that way LOL.

Concord Trainwreck 2019 - first attempt at winemaking from grapes, needed answers and found WMT
1.116 - 0.996 16.4%

Concord / Blackberry 2020 - no idea why I started so low with the SG on this one
1.055 - 1.002 7%

Concord / DeChaunac 2020
1.080 - 0.996 11.3%

Concord 2021
1.090 - 0.998 12.4%

No Concords in 2022, the vineyard I use had a lot of Steubens, a cousin of Concord in the v. labrusca family, but less foxy and a little more spicy.
Steuben 2022
1.090 - 0.996 12.5%

I usually (in the last couple years) do an EM on my grape wines. WM Magazine just had a great article on making wine from non- v. vinifera grapes that suggest limiting skin time to reduce foxy-ness. That's a try for this season. I made a rose from the Steuben doing saignee of the original batch. I'll have to follow up on how they taste. They have been bulk aging since last October in glass carboys.