Thursday, 9 October 2014

Which came first - the wine or the egg?

You may or may not have heard of a relatively new technique (or some would say trend) in winemaking where a concrete egg is used as the storage vessel. If you have not, then you are probably reading this thinking that I am crazy. Others would argue that this concept is not at all new and is, in fact, the ultimate fusion between ancient winemaking traditions and modern winemaking technology. 

Cast your imagination back around 7,000 years to Georgia, where it is claimed that wine was first produced on a significant scale. Here, they make their wine in clay pots (quevri) buried below the ground, and have done since any of them can remember. Grapes fermented and matured in this way are said to produce wine of exceptional flavour and complexity, reflecting the local terroir (the ultimate goal of a winemaker). 

Now, it is not just the Georgians that have been onto something good with well-insulated winemaking vessels. Many old French wineries still use concrete fermenters to this very day. From memory, I can even remember spying some old concrete tanks at Henschke in Australia.

Allegedly, the egg-shaped tank was originally commissioned by French winemaker Michel Chapoutier in 2001 in liaison with French vat manufacturer called Nomblot. However, after a falling-out of sorts (the details of which I will not bother you with here), Nomblot commenced manufacture but Chapoutier missed out on the rights. Chapoutier was an advocate for the biodanymic approach to winemaking and believed, based upon a series of trials over 2 years, that an egg-shaped concrete vessel could concentrate energy into a sort of vortex, which he saw as beneficial to the quality of the wine.
The Americans picked up on the technology as early as 2003 and it looks like the Canadians have not been far behind. I am excited to say that we have not one but three concrete eggs in use at our winery, and I am aware of other producers around the Okanagan who have them in use.

Our brand new 1600L concrete egg
Now, this whole concept may sound a bit far-fetched, but I did ask our winemaker to give me a run-down on why he chooses to ferment and mature some of his wines in concrete eggs. Here is a summary of the perceived benefits of the concrete egg:

1. Concrete is inert but porous.
This means that the vessel does not impart any flavours into the wine but does allows micro-oxygenation to occur. Basically, you get the benefits of rounder mouthfeel that an oak barrel provides, without imparting any additional flavours into the wine which can mask the natural expression. You also keep the intense fruit flavours, which is what stainless steel is prized for.

2. Concrete is a natural insulator. 
This means that the material assists in maintaining a consistent temperature for the contents both during fermentation (which is essential for a happy yeast culture) and afterwards, when wanting to ensure the wine is experiencing optimal ageing conditions and minimal disturbance.

3. The shape of the egg creates a convection current.
Some claim that thermal layers within the egg, due to its shape, creat a convection current whereby warmer wine is constantly rising and cooler wine falling, resulting in an extremely well-integrated end product. Furthermore, if fermentation is conducted inside the egg the resulting vortex continually and naturally mixes the lees, leading to better mouthfeel in the wine, without the labour-intensive process of battonage.

Identical 600L concrete eggs
If any of the above has convinced you that there may be some benefits in the use of these mysterious concrete eggs, you may be wondering why more wineries have not jumped on the bandwagon. Well, it comes down to cost and practicality. 

From what I understand, the capital outlay of purchasing an egg works out at approximately $10/L of wine. On the other hand, over time, this may outweigh the ongoing cost of purchasing new oak barrles.

Another point is that concrete is much harder to sanitise than stainless steel, as it can tend to be slightly basic in nature and requires neutralisation with Tartaric Acid prior to use. Also, there may be more risk of microbial contamination and, as a result, more care is required in maintaining the vessel.

The debate of the egg aside, the fact is that I am lucky enough to be witnessing these crazy vats in action first hand. This week, we have just put some Rousanne and Viognier into our eggs, so I look forward to keeping you posted on my observations of the development of these wines over the vintage.