Tuesday, March 24, 2009

Milliliters, Milligrams and Millimeters - Part II of the "Joy of Bottling"




Today, on Saint Patrick's Day our very first unfined and unfilitered wine made its final journey and is now sealed in glass. I cannot impress enough upon everyone how exceedingly difficult it is to make truly great wine much less to get it past the final hurdle and into bottle. We have put everything we know and everything we have into Vellum and yet our success is measured by milliliters, milligrams and millimeters.

Putting a cork into a bottle of wine properly requires an understanding of temperature, vacuum, and very close consistent tolerances in the head-space between the wine and the cork. The temperature of the wine cannot be too cold. If there is too great a difference between the wine and the ambient temperature, it will expand in the bottle when it warms up and quite possibly push up the cork even under a vacuum.

Being the mindful types we are; the wine came out of the tank at 58-60 degrees F and went into the bottle at about the same temperature. We maintained a head-space between 12-14mm in each bottle, giving the wine a chance to move if the worst should happen (exposure to heat)...Let's hope not. I like to think that everyone stores their wine responsibly!

It is also worth considering the amount of dissolved oxygen is the wine. This measurement is important to protect the wine from any infection that could happen in the bottle. At Vellum we will not fine or filter our wines. Fining is a process by which undesirable constituents are removed from a wine during the winemaking process. The other side of this process is that fining agents do not discriminate and they will remove the good stuff too! Filtering, while making a wine more biologically stable and microbe free can also strip out a wine very quickly leaving it listless. In most cases may take months afterward for it to re-integrate (if at all) to its former state.

So, our only weapons to make sure that Vellum goes into and develops in bottle infection-free, is impeccable hygiene and good numbers. We keep everything sanitized from our barrels to our equipment but also it is the nature of our wine that keeps any yeast or bacteria from growing in it. The wine is dry (no sugar in it) and virtually free of malic acid. Both of these can be food sources for yeast and bacteria respectively.

Also, Vellum has a comparatively low pH by Napa Valley standards. Not only does this contribute greatly to sensory properties but it is an inhibitor of infection. As mentioned, the dissolved oxygen level has been brought down below 1 mg/L where normally it can range from 4 to 6 mg/L . So, when the wine hits the bottle anything in it that requires oxygen to live (aerobic yeast or bacteria)- will not thrive.

As a reminder, when you can no longer resist the temptation to drink the wine, please let the bottle breath upon opening. It needs oxygen to "wake it up" and you will find that your drinking experience will be much more pleasurable.

Finally, for aesthetic purposes, once we have finished corking the wine we needed to put the capsule on it and have the labels strategically placed. The package for Vellum has become a reflection of what is in the bottle but unfortunately getting it right can be an exacting task. So, the labels have to be placed with tolerances of 1-2mm and the foils have to go on with the right amount of torque without breaking or even stressing the bottles. There also should be no folds during the process and this perhaps is the most tedious task and requiring many eyes as the bottles come off the line and into their cases.

Which reminds me... I want to take this opportunity to thank all twelve? (I think I counted correctly) people involved in the bottling of the 2007 Vellum vintage. They demonstrated great skill and professionalism over the two days and they met our needs without hesitation. When working with solid people like this, it makes a seemingly trying event much more bearable and gratifying. Again, my thanks to everyone involved and to everyone who purchased futures of our first vintage, we are eagerly anticipating the release as much as all of you are in May.

- Karl Lehmann

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