Black Grapes

[distancerunner]

Just to clarify, the plan is to use a drill and mixer for punchdowns?

 

[David Violante]

I’ve been using the mixer as a punch down tool by hand, much as you would use a …regular?… punch down tool. I did find it helpful to mix things up at the bottom and when I added some tartaric acid and nutrients at the beginning. I tried a large paddle but the must was really thick. A slow speed on the drill did the trick. Haven’t used the drill since though. The best part is that it was $15.

We’re down to between 5 and 10 brix among the three vessels, and maintaining 76F. I did place a box fan in the window which has been really helpful.

Thumbnails below:

 

[distancerunner]

That works!

 

[David Violante]

SG made it down to 1.010 and I pressed to quite a few glass carboys yesterday. Took a heck of a time with a 25# press.



Fermenting still going on in the carboys this morning but I sense a bit of H2S. At first I thought it was the CO2, but it’s nagging me. Not sure why it’s there, I even upped the nutrients.

I added a double dose of SO2 and the SG is just about 0.998. As I understand it, splash racking is helpful prior to going towards something like Reduless. While I want to nip this early, should I wait a few days until the gross lees are somewhat compacted and rack off of them and then splash rack?




There’s also a 14 gallon demijohn not in the picture.

 

[winemaker81]

I added a double dose of SO2 and the SG is just about 0.998. As I understand it, splash racking is helpful prior to going towards something like Reduless. While I want to nip this early, should I wait a few days until the gross lees are somewhat compacted and rack off of them and then splash rack?

Stir the wine vigorously now to drive off the H2S. If you have it, you'll certainly know it when you start stirring. My understanding is there are two issues involved -- one is stressed yeast producing H2S and the other is the H2S forming mercaptans. K-meta and stirring will handle the H2S.

Since you caught it early, that may be all that is necessary. Don't be in a hurry to use Reduless, unless you need it.

 

[David Violante]

Stir the wine vigorously now to drive off the H2S. If you have it, you'll certainly know it when you start stirring. My understanding is there are two issues involved -- one is stressed yeast producing H2S and the other is the H2S forming mercaptans. K-meta and stirring will handle the H2S.

Since you caught it early, that may be all that is necessary. Don't be in a hurry to use Reduless, unless you need it.

Understood - if the gross lees have settled out but not yet compacted, I imagine racking off them would be helpful as well? I could then let the collected gross lees compact and see how that segregated wine fares. If good, add back, if not, feed the septic system.

 

[winemaker81]

Understood - if the gross lees have settled out but not yet compacted, I imagine racking off them would be helpful as well? I could then let the collected gross lees compact and see how that segregated wine fares. If good, add back, if not, feed the septic system.

IMO that's a good approach.

 

[David Violante]

I think your estimates of must/finished wine are in the right ballpark. The calculation that I use comes out a bit higher: 828lb (0.414T) = 53gal/200L finished wine, 88gal/333L must of which 31gal/117L is must solids

Racked off the gross lees into 54L demijohns and the smell is ever so slight. I’ll stir a few more times for that and to help the release of CO2. Should the stirring (using a lees stirrer / degasser) draw down air or just enough to release gas?

Also, started with about 80 gallons must, finished with 50 gallons wine. About a lug and a half or so didn’t make it to the crusher. Below the dark colored carboy is vino and the lighter one is the remaining solids compressing.

 

[BarrelMonkey]

Nice! If you have a convenient space, i would put that carboy with the leftover/compressing lees up on a shelf/bench/countertop so that you can easily rack it off without needing to pump...

 

[David Violante]

Update on this project - it has been a most wonderful experience with a lot of learning on my part.

A few weeks ago I noticed a white film on the top of the wine in two of the demijohns. That's odd, I thought. It was fragile and broke up a bit and some floated down into the wine while the rest I was able to pull up with a paper towel. There was a slight hint of vinegar prior to cleaning and none afterwards. The wine tasted and smelled good otherwise. I dosed with SO2 and cleaned / sanitized / replaced the bungs and airlocks. Last week I saw the same thing happening and thought, what the heck?! I did all the same things and then it struck me. What's the pH? 3.7 at last check, 3.7 now.

According to the chart of ppm free SO2 necessary against a particular pH, I would need 55ppm or 55mg/L. According to several online winemaking SO2 calculators, I would need to add 5.16G of KMBS to a 54L Demijohn to achieve 55ppm. According to my scale that's a full teaspoon.

What I HAD been doing, was adding 1/4t per 5-6 gallons, which ends up being 3/4t for a 54L (14.27G) Demijohn. I had not considered the pH. Another lesson.

So, all of my additions were lower than what they needed to be, and after having splash racked for H2S, I'm sure were also not enough to protect the wine that now had some additional oxygen in it. I didn't do MLF because of the original pH, but am thinking I should have, to eat up some of the resources of other bacteria. I could have always added tartaric to lower the pH. Another lesson.

Here I am today with a few more lessons learned. I'll add an actual double dose of SO2 and I purchased Bactiless just in case.

I'm open to any thoughts and suggestions too...!

 

[BarrelMonkey]

So looking back it seems like you started fermenting end october, so about 2 months in? If you added a double dose of Kmeta back when you hd a hint of H2S, I doubt MLF will be successful at this stage. MLB are sensitive to SO2 and it seems that the total SO2 added (rather than free SO2) is the relevant factor.

How does it taste? I always find it hard to evaluate red wine at this early stage, but you should at least be able to get some sense of acidity, fruitiness etc as well as any overt flaws. If it seems on track, I would not be inclined to worry unduly. Certainly, clean out any growth around the neck of your demijohn and sanitize the area with KMBS spray or alcohol, but then I'd just keep doing what you're doing, ie monitor and add KMBS at appropriate intervals.

Do you have any means of testing for SO2? The '1 tsp = 55ppm' rule is a reasonable strategy, but since you've already added quite a bit of KMBS (and are targeting a high-ish level) it would be nice to make data driven additions if possible.

Finally I wouldn't be overly worried about the high pH. There are many GREAT wines in that pH 3.7-3.8 range, they just need a bit more attention to make sure opportunistic bugs don't take hold.

 

[David Violante]

Thank you for your sage advice and reassurance~

I haven’t tasted any off flavors previously and will work on doing an aeration/oxidation SO2 test tomorrow. It just hadn’t occurred to me as I thought I was in the right place. Another great reason to take notes. I can look back and see trends I may have missed at the time but which pop out now (splash racking introducing oxygen and pH being higher).

I’ll post results~ thank you again!