Update on the Fate of Our Chardonnay Experiment

On September 28, 2019, with the help of our friends, we harvested a small amount of Chardonnay. We thought we had about 290 pounds of grapes. Our friends helped us to stomp on the grapes which we put into mash bags as whole clusters and collected the juice as gravity flow into the kegs waiting in our basement. When this process was done, we had juice in three kegs. The largest amount went into a 15 gallon keg and we thought we had around 12 gallons of juice. The remaining juice went into two smaller kegs each containing around 6 gallons of juice.
The experiment we conducted with this small amount of juice was to see how three yeasts, X16, D47 and CH9 affected the aroma and flavor profiles of the resultant wine. We inoculated the kegs on October 3, 2019 and the fermentation took over three weeks to come to completion. While the X16 and D47 inoculated wines were in a temperature controlled fermentation chamber, the CH9 was fermented outside of the chamber since we didn't have enough space for it.
I blogged about the properties of these three yeasts on January 11, 2020 in a blogpost called Chardonnay Fermentation Experiments. In May, we checked the sulfur dioxide levels of the three kegs and added some potassium metabisulfite where necessary. The wines sat on the lees until November 18, when we took the numbers for the finished wine:

Chardonnay/Yeast	pH	TA	SO2
Chardonnay/CH9	3.11	6.0 g/L	27 ppm
Chardonnay/D47	3.00	7.9 g/L	11 ppm
Chardonnay/X16	3.07	7.3 g/L	41 ppm

On December 8, 2020, we racked the wines off the lees into clean kegs and let it warm to "room temperature" in preparation for bottling. My husband then cleaned all of the components of the bottling line. Sanitation is key to good bottling! My husband also calibrated the filler to accommodate the different bottle types that we were using.
We bottled our Chardonnay on December 12, 2020. Here is the setup of our bottling line.

In the above photo, we used argon gas to push the wine that was in the keg. The keg coupler when open allowed the argon into the keg to push the wine into the tubing which went to the 1 micron filter. The pressure gauge was there to ensure that the appropriate amount of pressure was going to the filter. If the filter got clogged, the rising pressure on the gauge will indicate that problem. Next, my husband opened up the top of the filter to allow the first of the wine to flow out and ensured that there were no bubbles trapped in the filter. Prior to bottling, we blew compressed air into the bottles to get rid of any particles if they were there. Once everything checked out we were ready to bottle.

We could fill 6 bottles at a time. I filled the bottles and my husband corked the bottles. It was a smooth 2 person operation. When all the Chardonnay was bottled, we had the following:

Chardonnay/Yeast	Number of 750 mL bottles	Number of 375 ml bottles
Chardonnay/CH9	21 bottles	0
Chardonnay/D47	20 bottles	0
Chardonnay/X16	3 cases	2 cases

So, what did our experiment show? The Chardonnay fermented with X16 and D47 had great aromatics. The X16 smelled like apricots and orange blossoms while the D47 had an aroma like pineapple. My husband and I both didn't detect any aroma from the CH9 and we think it may be related to the fact that the fermentation occurred outside of the temperature controlled fermentation chamber. The next step is to see what bottle aging does to both the aroma and the flavors. Can't wait!

Chardonnay Fermentation Experiments

Our harvest of the Chardonnay occurred on September 28, 2019. Since we had such a small amount of grapes, we were able to handle this fermentation in our basement and our friends helped us to extract the juice by stomping on the grapes. The juice went by gravity flow into our basement into the waiting stainless steel kegs where the first step was the cold settling of the larger pulp matter.
We harvested about 290 pounds of Chardonnay, which turned out to be approximately 26 gallons of juice, enough to try three small experiments on fermentation with different yeasts. We chose X16, CH9 and D47 for the fermentations. Our goal is to see if there is an organoleptic difference imparted by the different yeasts on the resulting Chardonnay wines.

Here is what we know from the product data sheet of X16, CH9 and D47:

Yeast Strain	Fermentation Characteristics	Aromatic Characteristics
X16	→Rapid fermentative kinetics →Alcohol tolerance up to 16% per volume →Tolerance to low temperature fermentation (53 ℉) →Low nitrogen requirements →Tolerance to low turbidity →Low production of volatile acidity and H2S	→Very high aromatic production of white peach, white flowers and yellow fruit
CH9	→Alcohol tolerance up to 16% per volume →Fermentation temperature: 57 – 60 °F →Average nitrogen requirements →Short lag phase	→Fresh almond and hazelnut, toasted bread and citrus fruits
D47	→Alcohol tolerance to 15% per volume →Low nitrogen demand →Short lag phase and moderate fermentation vigor →Low to moderate production of H2S →Ideal for barrel fermentation	→When left on lees spicy, tropical, citrus notes develop and the wine is said to have a silky persistence

The fermentation step of the wines inoculated with CH9 and D47 took more than three weeks to go to dryness. The fermentation inoculated with X16 took about 6 weeks to complete because we kept the temperature around (53 ℉). We took the fermented wine data and it looks like this:

Variety	Yeast	Volume of Wine	pH	TA
Chardonnay	X16	12 gallons	3.24	12.8 g/L
Chardonnay	CH9	6 gallons	3.20	10.4 g/L
Chardonnay	D47	6 gallons	3.15	13.2 g/L

2019 Passionfruit Estate Chardonnay

We bottled our 2019 Chardonnay on December 12, 2020. When we harvested our 2019 Chardonnay, we had approximately 26 gallons of juice so we split the harvest into 3 lots and inoculated it with 3 different yeasts, X16, D47 and CH9, all fermented in stainless steel. After fermentation, the wine sat on lees for 15 months before bottling.
On January 9, 2021, we tasted a 375 mL bottled of the Chardonnay fermented with X16. We thought that there was an aroma of orange blossoms but it was still searingly acidic. While we are not afraid of acid, we know that the typical Chardonnay consumer may not be used to this level of acidity.
Last night, we tried another bottle of our 2019 Chardonnay, this time fermented with D47. The aroma was one of white peaches and apricot. I thought the acidity on the D47 fermented Chardonnay was not as assertive as the Chardonnay fermented with X16. It could also be the result of being in the bottle just a bit longer than when we tasted the X16 fermented Chardonnay.
We paired the Chardonnay with gnocchi. I love gnocchi and when I read somewhere that there are good varieties of pre-made gnocchi, I couldn't resist. My husband cooked the gnocchi in sage browned butter with peas. It was a delicious pairing with the Chardonnay. After dinner, we agreed that to send the gnocchi over the top, my husband could also have put in some pancetta!

Tasting Our 2019 Chardonnay

Last night, we tasted the third experiment of our 2019 Chardonnay where we fermented small batches with three different yeasts. We used X16, D47 and CH9 to do the fermentations and so far we have tasted the X16, D47 and last night we tasted our Chardonnay fermented with CH9.
When we bottled the CH9, we were surprised that there was very little aroma compared with the X16 and the D47. But last night we did detect a bit more aroma developing in the bottle. I thought it smelled a bit like anise. We paired the Chardonnay with chicken in a creamed sun-dried tomato sauce over gnocchi. Yum.

Tasting Our 2019 Chardonnay

Yesterday, we decided to taste our 2019 Chardonnay fermented with the X16 yeast that we bottled on December 12, 2020. It's almost a month since we bottled it and my husband had the perfect meal to pair with the wine. He made a wild sockeye salmon with the Florida Seasoned Pepper from Penzeys. We had a side of green beans to go with the dinner.
The Chardonnay that we tried was one of our 375 mL bottles. Good for two people. As we swirled the glass, I detected the aroma of orange blossoms. The flavor was also of oranges with a decided acidic kick at the finish.

This is interesting because the titratable acids are only at 7.3 g/L, although the pH is 3.07. We'll taste this wine again after it has a few more months of bottle aging to see if the acids marry with the other components of the wine. All in all, we thought that it was our best attempt at making Chardonnay so far.