2019 Late Harvest Chenin Blanc Next Steps

We brought in our late harvest Chenin Blanc on Tuesday, November 19. We might have had about 50 pounds of fruit which gave us around 4 gallons of very dark juice. We emailed our friends and mentors Charles and Kareem Massoud of Paumanok Vineyards.
Originally, we had the juice in a 54 degree fermentation chamber for settling for a day, but Charles advised that the settling should be done under much lower conditions so on Wednesday, November 20, we moved the carboy into a fermenter where we set the temperature to 38 degrees. The carboy sat in the cold fermenter until Sunday, November 24. In the 5 days of settling the juice resolved itself from a dark olive green color to a lighter yellow color.

The result of the cold settling amazed us. We thought we would still get a dark juice, but it clarified to a nice yellow color! What was left behind in the sludge was most of the undesirable dark pulp. We racked the clarified juice over to a 5 gallon keg.
When we took the numbers on the clarified juice, it appeared that we lost a bit of tartrates during the cold settling:
Brix = 25
pH = 3.5
TA = 9.1 g/L
We let the juice come up to 54 degrees overnight and then inoculated the must with VIN13 on Monday, November 25 at 3:45 p.m. Our next task is to carefully monitor the fermentation so that we can stop it at the desirable level of residual sugar in order to create the moelleux style that we are hoping to achieve.

Last Harvest of the Year

This year we conducted an experiment in the vineyard. We still have a few rows of Chenin Blanc that are not producing enough fruit to warrant putting up netting, so we resorted to our tried and true method of putting wedding bags on the scattered Chenin Blanc grapes. We had about 500 wedding bags in the vineyard and decided to leave them on the vine after we harvested the bulk of our 2019 Chenin Blanc on October 14.
Our goal was to see if we could make a sweet wine, in the style of Domaine Huet Vouvray Le Haut-Lieu Moelleux. So, we left the grapes on the vine until it was more than a month past our last harvest. On Tuesday, November 19, we went to harvest the Chenin Blanc. We went to the land at 2:30 and finished harvesting all the wedding bags at 3:45. The more time consuming part was ahead. We had to debag the grapes and stomp them!
Here is what our late harvest Chenin Blanc grapes looked like:

It's not the prettiest looking grape and had undergone several freeze/thaw events but they were still intact. We resorted to our typical stomping of grapes and got perhaps 4 gallons of juice.
We were so surprised that the juice was almost black in color. Looking on the Internet, however, showed that this is kind of typical for late harvest juice. We took the numbers for the juice and here is what we have:
Brix = 25
pH = 3.52
TA = 11.2 g/L
We initially had the juice settling in a 54 degree environment, but upon advisement, we lowered the temperature to 38 and are continuing to setting the wine. I'll give updates on our experiment so stay tuned.

Progress Report on Our Cabernet Franc and Cabernet Sauvignon

We harvested our Cabernet Franc on Saturday October 26 and our Cabernet Sauvignon on Sunday November 3, and brought both harvests to Jonathan Edwards Winery to have Michael and Alex help us with the destemming, crushing and fermentation.
During the fermentation, we participated in punchdowns over the weekend and now it was time for the wine to be separated from the spent grape skins and seeds. We were very fortunate that Michael had a small basket press that was never used. We went to Jonathan Edwards Winery on Monday, November 19 around 2 p.m. and Michael and Alex had already done one pressing of the Cabernet Franc.

This is what the spent grapes looked like and the wine that was pressed from the fermented grapes.

Since Michael and Alex had never done a pressing on such a small quantity, they devised this clever idea to get the juice into the waiting barrel. The basket press on a pallet was elevated by a fork lift above the waiting barrel.

The Cabernet Franc grapes/wine must was put into the barrel.

Even before the pump was turned on, the free run came out of the grapes. After turning on the pump to inflate the bag inside, the wine was released from the grapes. The pressure applied to inflate the bag was 1 atmosphere, or 12 pounds. I felt the spent grapes and it was like dust!
Here is a photo of the wine flowing from the press.

Alex thought that we might have 30 gallons of wine! The wine will sit overnight in the barrel and then be racked into a 30 gallons closed top barrel for malolactic fermentation.
Thanks Michael and Alex! We really appreciate your help!

Malic Acid in Grapes: Part 2 Chemical Structure and pKa

Recently, I wrote a blog about Malic Acid in Grapes: Part 1. In this blog, I'm going to take one step back and spend a little time on the chemistry of malic and tartaric acids.
The chemical structure of malic and tartaric acids looks like this:

Malic and tartaric acids are dicarboxylic acids. The red circles indicate the hydrogens on each molecule that ionizes in solution to yield free hydrogen. The ionizable hydrogens are part of the hydroxyl group of the carboxylic acid [-COOH] moieties. A solution’s pH is really just a measure of the concentration of these free hydrogen in the solution.
The strength or weakness of an acid, or how readily the hydrogens ionize from their parent molecule is defined as the pka, each acid’s pKa value(s) provides some indication of the degree to which each acid is ionized.
Malic and tartaric acids are weak acids. The pka of these weak acids refer to the conditions under which these molecules will allow the separation of hydrogen into the solution, in our case, we are talking about wine being the solution.
Here is a chart of the pka values for malic and tartaric acids. The blue line represents the fraction of the acid that is unionized, the red line represents the singly-ionized acid, and the yellow line represents the doubly-ionized acid.

Since malic and tartaric acid both have two protons which may be lost to the solution, there are two pKa values for each acid. For malic acid, the pka values are 3.4 and 5.2 and for tartaric acid, the pka values are 2.95 and 4.25. The chart shows that acids with different values of pKa will have differing effects on pH.
At the lowest levels of pH, the acid exists in solution in the un-ionized state, but at pH levels between the two pKa values, the singly-ionized state is the most populated, and then at pH levels much above the higher pKa value most of the acid is present in the doubly-ionized state.
At a typical wine pH of 3.4 (the value of pKa1 for malic acid) half of the malic acid would be un-ionized and therefore contribute nothing to the pH of the wine. However, in the case of tartaric acid at pH 3.4, most of the acid will be in the singly-ionized state, and there will also be some un-ionized and doubly-ionized states present, contributing to the pH of the wine.
References:
1. Rochester Area Home Winemakers.
All structures were drawn by the freely available drawing program from ACD Labs called ACD/ChemSketch Freeware.

Trip to Long Island Wine Country

What did we do on our day off? After the harvest is in and the wines are fermenting, what a better time than to go to Long Island to visit Wine Country. It's fair to say that we can't get enough of wine and learning about wine.
We had a specific reason for going to Long Island and it dates back to Our First Visit with Charles Massoud at Paumanok in 2011.
As it turned out, Monday was a beautiful day and when we reached Orient Point, the temperature was 64 degrees! Last year, when we made this same pilgrimage, the weather gods were kind to us and provided us with possibly the only two beautiful days in an otherwise very miserable fall of 2018.

We had an 11:30 appointment with Charles and Kareem Massoud at Paumanok.
We were a little early for our appointment so we made a detour to Lenz Winery, one of our other favorite wineries to visit on Long Island.
A new thing that I saw at the tasting room was that the winery now offers something called "tastings" in which you can select specific wines to taste for a slightly larger pour than the regular flight of tastings. We opted to taste a 2016 Cabernet Sauvignon, 2014 Cabernet Sauvignon and a 2014 Merlot. My husband and I really liked both the 2016 and 2014 Cabernet Sauvignon so much that we purchased some bottles to take home with us. After this small detour, we headed to Paumanok.
We met up with Kareem and he showed us his 2019 Cabernet Sauvignon which had finished fermentation and was now being pressed. It was just amazing to see so much Cabernet Sauvignon being pressed. The aromas coming out of the juice was just amazing!

During previous rendezvous, Charles always brought out all kind of cheeses and pates for us, so this year, we brought some light bites from Connecticut with us, including smoked bluefish and summer sausage, complements of our hunter.

We met up with Charles and had a wonderful visit and then it was time to run off to catch the ferry back to New London. We thank Charles and Kareem for their hospitality!

Malic Acid in Grapes: Part 1 Our Titratable Acid Conundrum

This year has presented us with a bit of a conundrum when we began to check on the Brix, pH and titratable acidity (TA) of our various grapes. We have always encountered high TA in our Chenin Blanc, but this year, we encountered high TA in our Cabernet Franc as well as our Cabernet Sauvignon. The puzzle was that the Brix were also high. In looking back at this year's growing season, we felt that we had good weather throughout the summer which would explain the high Brix, but what was puzzling was the high TA which never seemed to come down even though we let the grapes hang on the vines as long as possible.
Here are our numbers in the order in which the varieites were harvested:

Variety	Harvest Date	Brix	pH	TA
Auxerrois	September 23, 2019	19.6	3.26	7.35 g/L
Chardonnay	September 28, 2019	21.5	3.17	9.4 g/L
Chenin Blanc	October 14, 2019	21.6	3.15	13.5 g/L
Cabernet Franc	October 26, 2019	23	3.32	11.3 g/L
Cabernet Sauvignon	November 3, 2019	21	3.00	14.9 g/L

Looking at the high titratable acids, we wanted to know more about the role of malic acid in grapes. There is a beautiful diagram that shows grape berry ripening and the changes in grape metabolites during ripening.¹

I used the above diagram in a previous blogpost called Two Stages of Grape Berry Development, but in that blogpost, I focussed on the changes that occured in the grape berry in stage one and then in stage two.
In this and subsequent blogposts, I'm going to focus on the fate of malic acid in the ripening grape. Stay tuned!
Reference:
1. Moschou, Panagiotis & Aziz, Aziz & Roubelakis-Angelakis, Kalliopi, Chapter 7, Polyamines and grape berry development, The Biochemistry of the Grape Berry, (2012), 137-159.

2019 Cabernet Sauvignon Harvest

We called on our friends for one more harvest, our Cabernet Sauvignon. We harvested on November 3 on what was a perfect Sunday fall afternoon.
We began at noon, with our early bird friends who came to help us with raising the netting. We accomplished that task by 12:30. So, even though the harvest time was set for 1, we began harvesting. Some of our friends came after 1 p.m. and while they were too late to harvest, they helped us to gather up the lugs and store it in our container for transportation to Jonathan Edwards Winery on Monday morning.
Here is our crew celebrating the penultimate harvest for this year.

On Monday morning, we brought our harvest to Jonathan Edwards Winery and learned that our harvest weighed 332 pounds!

The grapes will be destemmed and gently crushed and sit overnight before inoculating with the yeast, F15.

2019 Cabernet Franc Fermentation

We harvested our 2019 Cabernet Franc on Saturday, October 26, 2019 and took the harvest to Jonathan Edwards Winery on Monday, October 28, 2019 where the harvest was weighed, destemmed and mildly crushed. The must sat in the half ton bin overnight.
On Tuesday, October 29, we rehydrated the yeast of choice, FX10 with the help of winemaker, Michael. Our choice of yeast for this year is a departure from last year, when we used F15 to ferment our first Cabernet Franc.
Michael estimated that we might get approximately 32 gallons of juice. Using that estimate, we rehydrated 32 grams of FX10 in 320 mL of water and waited for it to bloom, which took around 20 minutes.
In the meantime, Michael gave me a taste of their Chardonnays that were fermenting in the barrels as well as the Chardonnays fermenting in their stainless steel tanks. It was delicious!
After the time was up, we took an aliquot of the Cabernet Franc from the half ton bin:

We used the juice to temper the rehydrated yeast:

The must was inoculated with the tempered and rehydrated yeast at 10:40 a.m. The must at the beginning of fermentation was:

Variety	Brix	pH	TA
Cabernet Franc	23	3.32	11.3 g/L

The fermentation began on October 31, 2019. Michael and Alex decided to move the must from the half ton bin into a 55 gallon blue barrel. Daily punchdowns are being done. Today, it was our turn and my husband took photos of me doing the punchdown. The cap initially is a little difficult to break through but once the cap is breached, the rest of the punchdown is easy to do.