On Jun 28, 5:59 pm, "Lum" > wrote:
> "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

Exactly what I was thinking, just follow Lum's advice to add it to a
sample first and not the whole batch. I think you are getting close
to having it where you will want it. Citric acid is usually a good
choice for touching up wine acidity. You don't have a pH problem so
that helps since citric won't swing pH as much as tartaric. Go by
taste now and then measure. You don't want to get too caught up on
the numbers; you are are making food not building a deck.

That is one of the problems with ML fermentation, you want that butter
so you need to do it. If you wanted it a little less complex but
tarter foregoing the ML might have been an option to consider. Your
grapes sounded pretty good so I would have done exactly what you did.

Joe