Chardonnay Fermentation

We have had small crops of Chardonnay since 2016 and have tried our hand at fermenting Chardonnay grapes into wine. We have to admit that Chardonnay is a trickier grape to ferment than either Auxerrois or Chenin Blanc. The reason being is that Chardonnay's varietal character (typicity) can be expressed in many forms. It can be steely and acidic like Chablis, or fuller-bodied and buttery like those from southern Burgundy or it can be a base wine for making Champagne. And just when you think that that is all that Chardonnay can do, Katherine Cole wrote about Black Chardonnay.¹

Chardonnay is among the world's most planted grape due to it's viticultural adaptability and enological malleability.² The question that we need to answer is should Chardonnay be vinified to emulate a classic Burgundy or should the varietal character be expressed according to our own region. So far, since we haven't had enough of a harvest to fill an oak barrel, we haven't been able to ferment and age in oak. We have done one stainless steel vinification and this year we have made a Pétillant Naturel from the harvest.
In our process, we:

• Harvest the grapes:
  What we try to do is to take utmost care of the vintage in the vineyard. When we cannot, we try to get the best grapes that we can by hand cleaning the clusters so that we only use the best grapes.
• Extract the juice from the whole cluster grapes via foot stomping:
  We put the whole cluster grapes into mash bags and foot stomp them a la I Love Lucy. Everyone who participates wears food grade booties. What foot stomping accomplishes is a gentle extraction of the juice, leaving behind the pectins that can cloud a finished wine.
• Cold setting the juice with 50 ppm potassium metabisulfite:
  We try to stop the fermentation of the juice by yeasts that come in from the vineyard. Cold settling also sediments out the heavier protein and pulp that might be in the juice. By doing this, we do not have to add fining agents such as casein, bentonite and PVPP.
• Kick off fermentation at 55-60 degrees F:
  A low and slow fermentation tries to capture as much of the floral aromatics that are part of the Chardonnay grapes.
• Monitor the progress of the fermentation
• End fermentation
• Age the finished wine
• Bottle the finished wine

In the case of our Pétillant Naturel, we monitored the decrease in Brix in our fermentation using glucose testing strips until it reached 2% or 20 g/L and then bottled it in champagne style bottles to finish the fermentation under crown cap.
There is so much to learn about the vinification of Chardonnay!
References:
1. Katherine, Cole, Meet Black Chardonnay, SevenFiftyDaily, August 3, 2017.
2. Sweet, Nancy, L., Foundation Plant Services, UC Davis, Chardonnay History and Selections at FPS, Foundation Plant Services FPS Grape Program Newsletter November 2007.