Happiness is Chromatograhphy

After the turn of the year I spend a significant amount of time checking and tracking the progress of malolactic fermentations (ML or MLF) in our new wines. This secondary fermentation is a bacterial fermentation or conversion of malic acid (think green apples) to lactic acid (think dairy acid). This conversion softens the acid profile of the wine and also supplies a degree of stability as malic acid is essentially food for a number of spoilage organisms.

Most of our wines complete 100% MLF, save our Gewürztraminer, Riesling, Pinot Gris and stainless-steel Chardonnay. We add SO2 immediately after primary fermentation to block the MLF from occuring.

When the conversion is complete we can then add SO2 to our wines for protection (SO2 is inhibitory to the bacteria that perform the fermentation).

One of the ways we track the fermentation is by using paper chromatography. This is a relatively 'old school' technique for tracking the fermentation. It uses the principles of chromatography (essentially a substances affinity for a solvent) to separate the acids present in the wine. It's a bit convoluted but it is a pretty easy method for getting a basic idea of your MLF progress.


The rack above contains 60 test tubes, each representing a single barrel of wine. They are coded with a letter and number (A1-A10 though F1-F10) so each barrel is identified. Using special chromatography paper, I 'spot' 10 wines per page with a tiny capillary tube; the smaller the spot the better. After passing over each spot three times i leave the paper to dry.



When dry I roll the paper into a tube and staple it together. The tube is then placed into a sealed container that contains a small amount of chromatography solution. I leave the paper in over night.

Tomorrow I'll take the paper out, develop it and read the results. Ill post a pic of the results tomorrow afternoon and we'll see where we stand

SO2 and Camels

The above apparatus is used to run an Aeration/Oxidation test for free sulfur dioxide (SO2), a winemaker's primary tool in fighting oxidation and to a lesser extent microbial spoilage. It looks pretty 'mad-scientist'-like but it's relatively practical chemistry at work.

The pear-shaped flask at the bottom contains the wine and a big dose of acid, which combined with aspiration (pulling some air though the solution with a vacuum pump) liberates the free SO2. The free SO2 essentially travels up through a condenser (cold water) and is trapped in the solution in the top flask. The top flask contains hydrogen peroxide (H2O2) and an indicator solution/dye. It begins the test a green color and turns purple in the presence of the SO2. We can then titrate this solution with Sodium Hydroxide (NaOH) to calculate the free SO2. Ill spare you the boring details of the chemistry, its pretty easy and fairly accurate; it's downside is that it takes 10 minutes of aspiration to run a test.

We began another round of racking in the cellar this week. Ryan racked our 2006 wines from the Camel Hill Vineyard(Merlot, Cab Sauv, Cab Franc and our Lexington Meritage (so far 68% Cab Sauv/20% Cab Franc/12% Merlot)) to tank yesterday. While he was washing the empty barrels i ran analysis (Free SO2, VA (Volatile Acidity), pH and TA) on the wine in tank. We are going to do a little blending, correct the SO2 and return the wines to barrel.

I feel like I have a pretty good gauge on where these wines are going at this point in their life. 2006 is a much more classically styled vintage, especially when compared to 2005. The 05's needed ever day of the almost 2 year we gave them in barrel, while the 06's should be ready for bottling in another 4-5 months. The are much more suave and nuanced; the 05's are much more structured.

The Lexington and Cab Franc have darker and denser flavors- think blackberry and coffee. We only have a single barrel of Camel Hill Cab Sauv and it is getting blended into the remaining Camel Hill Merlot. It added a little more heft to the Merlot and filled in the mid-palate nicely.

I am headed up to Tahoe early tomorrow for a little snowboarding action; got a new board last week and am super excited to try it out.

More soon....