"Darin" > wrote in message
oups.com...
Hello all -

I made a barrel of Chardonnay this year from fresh fruit, and I
thought I'd appeal to the group to help me understand and solve a
couple of issues that have arisen.

I started with a ½ ton of BC Okanagan Chardonnay grapes, night picked,
when sugar content had reached 23 Brix and my farmer thought the
grapes had sufficient maturity. After crushing the following morning,
I measured 7.10g/L TA with pH 3.37.

I cold fermented at about 55 degrees F, warmed and ran ML (ah, and the
enjoyable butter it did produce!), and upon completion added S02 and
cold stabilised in my garage (near freezing) till the end of
December. However, when tasting the wine for the first time since
chilled, I found it flat with a degassed pH of 3.80. Yikes!

I added 0.90 g/l tartaric acid (after trials) and schlepped my tanks
back into the pseudo-cold of a BC coastal winter. Before bentonite
fining at the end of March, I noted that more tartrate salts had
precipitated in the tanks, it still tasted slightly flat, pH was 3.58,
and TA was skulking around 5.70g/L. I popped in another 0.30 g/L
tartaric and let it sit in my cellar (55 degrees) until last week.

My current sample weighs in at pH 3.55 and may yet be a bit flat. I
was worried about more precipitation from my earlier 0.30 addition, so
I chilled a sample in the fridge for the last week - nary a single
crystal, though.

I wonder:

1. Why won't this wine precipitate any further tartrate when I added
0.30g/L after cold stabilisation? Is it stable?

2. If I add another 0.20 g/L, filter with 50micron nominal pads, and
then bottle, am I going to be seeing white crystals in my future?

3. How can I mitigate this problem next year? I've been considering
front-loading tartaric acid before ferment (even though my must will
likely originate around pH3.37 with TA 7.1) or even halting ML
midstream by means of early S02 addition.

I'm trying to get my ducks straight this year, but I'm also leading a
club next year, so any advice would most appreciatively be
appreciated.

Best Regards & In Vino Veritas
Darin


Darin,
Potassium bitartrate precipitation slows down when most of the excess
potassium is gone.
I would add 0.5 g/l of citric acid to a sample of your current batch of
Chardonnay and taste it. Citric acid wont precipitate, so it wont change
the stability and the slight "citric" taste often enhances white wines.
Lum