SG still at 0.9975, What would you do?

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Cap Puncher

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So we have a nice Cab Sav from Rattlesnake Hills Washington (thank you Winegrapes Direct) that has been fermenting for the past month. It started at Brix 24.1 (SG 1.1015). TA=7.1, pH 3.73 (after adjustments, original was pH=4.02 and TA=5g/L (added 1.1 g/L of tartaric acid and everything seemed to balance)). We used Biodiva on each fermentor to Brix drop of 3-4, then Bravo yeast on one fermenter and Avante on the other. We used fermaid O 40g/hL at cap formation and fermaid K 25g/hL at SG 1.065. I also delestaged at SG=1.065. We added Alpha ML at SG 1.075. We decided to press after 12 days on the skins at SG 1.000-1.002 because the seeds were a bit overly astringent. All went well. Pressed and racked of gross lees after 48hrs. The aroma is amazing! We now have a 14 gallons demijon and 2- 1 gal jugs (press cuts). The SG after 5 more days was 0.9975, a week later still at 0.9975. There is bubbling activity in the 14 gal demijohn, the 2-1 gal jug have none. ML is complete and the bubbles are larger looking (which seem like yeast bubbles rather than the smaller ML bubbles). The 0.9975 was verified with a Brix -5/5 hydrometer. This probably put the RS somewhere around 10-15g/L (1-1.5%) residual sugar. The pH is 3.84 (after degassing) and I was going to put is in my 15 gallon barrel. I am a bit nervous about spoilage with the higher pH and the ~residual sugar about 1-1.5%.

Would you let the residual sugar ride and sulfite? then put in the barrel.

Would you try to do a restart protocol to attempt to ferment totally dry?

Add a tad ( a couple grams or so) of fermaid O and wait a couple weeks to see if it will finish?

Thoughts?
 
The average customer in the US is purchasing a semi sweet wine, ,,, so the big question is do you like what most consumers like or a bone dry wine? ,,,, will it fit your style? how does it taste?

My reaction would be let it stay semi sweet.
a few more questions
The historical reaction circa 1900 would be if it is done fermenting it is done, “gosh,, only university people own a hydrometer , ,,, I don’t know what the sugar is but it tastes good”.
From a practical point you are putting in a lot of effort for two percent sugar.
From a lab point of view I wouldn’t trust it to be done without waiting a few months ,,, slow yeast can test ones patience.
Another commercial point of view is, if you have not degassed, just curious if small bubbles are on the hydrometer causing a high reading?
 
If it were my wine, I would let it sit in the demijohn for a while longer. What’s the rush? You’re not going to bottle the wine for well over a year, typically. If time lets you lower the SG a bit more, you’d be really happy. Let it sit for a month or more, maybe two…then barrel.
 
In the Pambianchi book, he says anything under 2g/L is considered dry, so I think you're good. Often the residual sugar is pentose, which shows up on the hydrometer but cannot be metabolized.

But I agree, let it sit a spell and see what happens. But it is likely that fermentation is done, and the wine sounds great.
 
A couple of years ago a wine stalled at 1.000, and when it didn't budge, I barreled it. 2 months later the fermentation kicked in and it blew the bung a couple days in a row. Yeah, it took me a bit to figure out that the problem was as good thing, at least in the long run.

What is the temperature of the wine's storage area? I'd keep it in bulk at least another month and try to kick the temperature up to 75 F, or at least a few degrees higher than it is now.
 
A couple of years ago a wine stalled at 1.000, and when it didn't budge, I barreled it. 2 months later the fermentation kicked in and it blew the bung a couple days in a row. Yeah, it took me a bit to figure out that the problem was as good thing, at least in the long run.

What is the temperature of the wine's storage area? I'd keep it in bulk at least another month and try to kick the temperature up to 75 F, or at least a few degrees higher than it is now.

It been sitting about 72-75F, for the last 10 days. I have a heating pad on it to keep it up (my basement is about 63-64F)

I'll keep it going as long as it is bubbling, which it still is.

What would you do with the 2- 1 gallon press cuts? They at at about the SG 0.9975. They stopped bubbling after racking off the gross lees. Would stir the lees into suspension on the 14 gallon demijon, siphon out 2 gallon in 1 gallon jugs and mix in the 2 gallons of press cut that stopped bubbling? That's what I have been thinking of doing to make sure those finish as well. The press cuts still tasted nice at press.

The reason I am in a hurry to get the cab sav to complete is because I have a nice merlot in my barrel now that needs to come out. I'm afraid if I leave it in too much longer, it might get over oaked. I have another "Super Tuscan" that I took out of the barrel in a demijon (I'm lazy at bottling) that could take some more oak. I'll probably rack that into the barrel and let the cab sav sit for the next month.
 
What do you measure the SG with? I'm not used to seeing 4 significant digits to the right of the decimal point, and with hydrometers the third digit is a judgment call.

If all wines are at 0.9975, I don't believe it makes any difference -- all are in the same state.

Why is the demijohn on the gross lees? I'd rack all wines into a single batch, then rack back into the clean demijohn. That might kick things into gear. Also, if you can kick the temperature up another 5 degrees, that may help.

If you put the Cab into the barrel now, I expect you'll blow the bung at some point. Keeping it in the demijohn is (IMO) your best choice. Swapping the Super Tuscan into the barrel sounds like the best option. How old is the barrel?
 
What do you measure the SG with? I'm not used to seeing 4 significant digits to the right of the decimal point, and with hydrometers the third digit is a judgment call.

Bully for him, he is using a fine-scale hydrometer around 1.000:

The 0.9975 was verified with a Brix -5/5 hydrometer.
 
What do you measure the SG with? I'm not used to seeing 4 significant digits to the right of the decimal point, and with hydrometers the third digit is a judgment call.

If all wines are at 0.9975, I don't believe it makes any difference -- all are in the same state.

Why is the demijohn on the gross lees? I'd rack all wines into a single batch, then rack back into the clean demijohn. That might kick things into gear. Also, if you can kick the temperature up another 5 degrees, that may help.

If you put the Cab into the barrel now, I expect you'll blow the bung at some point. Keeping it in the demijohn is (IMO) your best choice. Swapping the Super Tuscan into the barrel sounds like the best option. How old is the barrel?

The hydrometer I got will measure SG 0.980 to 1.020 with 0.001 increments. (($13.99 at northern brewer). I am estimating the last digit because it is in the middle 0.997 and 0.998.

The demijon is NOT on the gross lees. As previously stated I racked off gross lees 48 hrs after press. The "lees" in the demijon I was referring too in the previous post was the light lees. I would think stirring the light lees into suspension before racking off 2 gallons would have more viable yeast cells go over with that racking. Then adding the 2 gallons of press cut (which has stopped bubbling).

I like your comment about going up 5 more degrees, I'll turn up the heat pad a bit and see.

My barrel had had a weird schedule, It is a 15 gallon Hungarian oak from Taosh Barrels. I first put the Merlot in for 2.5 months, then switched in the Super Tuscan for 5 months (over winter with cooler temps in the cellar (less oak extraction)). I then racked the Merlot back in and has been in for ~2 more months. I did this to give the merlot some new oak and 2nd oak (the barrel has heated up slightly to 60F now). The Super Tuscan only has a hint of oak after you have drunk a glass and smell the glass after. I could handle another 3-4weeks easily. Lots if life left in the barrel. I don't want to dry (I ruined a barrel previously by dry storing b/c my humidity is too low and the SO2 leaked out) or wet store if I don't have to.
 
The "lees" in the demijon I was referring too in the previous post was the light lees.
Gotcha, I misunderstood the lees comment.

If this was mine, I'd combine the demijohn + smaller containers, as it mixes in any active yeast in the smaller containers. I like the topup to be homogenous with the main batch, as it keeps the aroma and flavor consistent after topups.

The fine lees is probably dead yeast cells, so I'm not sure stirring will help, but it won't hurt, so I'd do that as well. I considered nutrient or more yeast, but it's so close to the end, it's probably not helpful. Mixing things up and adding more heat may do it.

My barrel was in a place where it got morning sun, and I think that is what kicked the fermentation back into gear. Since then those windows have heavy curtains, so it won't get that again. If you can move the demijohn to a position where it will get sun a couple hours per day, that may be sufficient.

I have a pair of 11 yo French oak barrels, long since neutral. I am using Hungarian medium toast cubes in the current wines, and am very happy. The barrels are both sound so I get the evaporation effect of barrel aging, and can add any oak I want to get the oak flavoring, including mixing species & toast levels.
 
Might be beating a dead horse here. .997 is done imo. Sometimes they ferment dry at .992. Sometimes .998. (‘dry’ meaning as dry as the wines able to go) But the wine makes the decision for ya. Any residual sugar is too small to restart….or even matter. Even at 1.010 the abv would be too high making a restart attempt pointless.

Also Mlf chroma tests don’t detect under 100g/L or something anyway so it’s advised to wait another few weeks/month after a seemingly complete test to ensure it finishes before racking & adding so2. Sometimes any last bits of AF will limp across the finish line during this time. Sometimes not.
To help it along you can stir the lees 1-2x/wk. Keep temps over 70°—and you can move the wine around without worry. Just don’t add so2 yet. If there’s anything left to ferment then it will. Could check SG again in a month. A watched pot never boils!

And for what it’s worth—- I’d call .9975 SG a successful ferment any day of the week.
 
@Ajmassa, you may be correct on this one. The vast majority of my grape wines finished at 0.996 or lower, but I've had a few a bit higher than that. Also, we need to consider calibration differences between hydrometers, and temperature adjustments. So yeah, let the wine rest another month.
 
I know the calibration on each of my hydrometers. My normal triple hydrometer and the SG 0.980-1.020 are both coming up with the same measurements +/- 0.0005.

As for the ML, the chromatography showed no malic spot at press. It has been 2 weeks at least. I think ML is probably done.
I usually don't co-inoculate ML and do sequential ML. Then wait usually 4-6 weeks before ML is complete. I then check final SG.

I only checked the SG because of the Co-inoculation of ML and wanting to get the Cab Sav in the barrel faster. This has probably happened before without even knowing.

Thanks for all the advice everyone! I'll heat up a bit and check the SG in 2 weeks (stirring every 3 to 4 days) or until bubbles stop.
 
Update: SG now at 0.9945! Still bubbling, added the two- 1 gallon press cuts today to make sure they will ferment out too. Aroma and taste are very nice. Patience is what the doctor ordered.
 
Last edited:
Oh yep: SG 0.9945
FYI: I have three hydrometers which I use. There is a 0.002 difference in the two triple scales from the wine toys stores, unless you have calibrated yours with salt solutions I would suggest you take the expected error in your hydrometer reading as plus or minus .001 therefore your gravity is 0.9945 +/- .001
 
Honestly I know what the error is in both of my hydrometers. I measured them both with distilled water at 60F (luckily my cellar temp was exactly 60F when I tested).
Triple = no error, exactly 1.000 at 60F. Pretty accurate.

0.980-1.020= 0.9975 at 60F (so I add 0.0025 to the final readings).

Cab Sav (~2weeks ago)=0.994 +0.0025 (customized correction) +0.001 (for temp)=0.9975.
Cab sav yesterday =0.991+0.0025 (customized correction) +0.001 (for temp)=0.9945.

Regardless of the correction factors the raw SG with my 0.9980-1.020 hydrometer went down by 0.003 in 2 weeks. My triple hydrometer showed ~the same.
 

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