VINEYARD AND CELLAR UPDATE
Due to the physical nature of juice and wine, the containers that are used for them need to comply with certain requirements and it sometimes does not only serve as container, but can also contribute to the development of the product or influence the quality detrimentally. Containers have also sometimes been used in the past without the scientific evaluation of their disadvantages or advantages. This does sometimes lead to the re-use of containers which have become unpopular. Concrete tanks which once occurred the most, were initially replaced by mild steel tanks, followed by stainless steel tanks, but concrete ovums have for different reasons become popular again. Amphorae made from clay, were most probably the first container used for wine and have after several years become popular again.
Clay containers were used in the wine industry since the seventh century BC and the ruins in Pompeii confirm that Roman amphorae were used for the fermentation, preservation and transport of wine. Amphorae are handmade clay containers, which take days to build and months to dry, before they are fired in a kiln. It can consequently rather been seen as a craft than manufacturing. Different cellars in different wine countries show interest in the use of it, because its properties and influences are better known. Different providers also contribute to its general availability to cellars.
A traditional amphora
Amphorae are usually 25 mm thick, in comparison with 125 to 150 mm of concrete tanks’ walls. As result of this thickness, steel fortification is usually required and coils are used for the heating or cooling of the contents. Contrary to that, clay is a good isolator and has a natural evaporation transpiration, which can cool the contents. Fermentation will consequently be slower due to the lower temperature. Clay also has a higher porosity than wood or concrete and more air (oxygen) will permeate through it. It can lead to a more rapid development of the wine, which implies that it can be bottled at an earlier stage. More minerality is also imparted to the wine. The inside of the amphora can be covered with bees wax in the traditional way, to limit permeability and wine losses. This can also impart interesting flavours to the wine. As result of the shape and mass of amphorae, they are more difficult to clean and move. It is also difficult to remove the pomace from them and they cannot be stacked.
The motivation for the use of amphorae differs between cellars. It especially finds approval with winemakers, who concentrate on unique wine characteristics rather than volume. It suits boutique wineries making wines in a traditional way from scarce or lesser-known cultivars and focusing more on the softening of the wines, than adding excessive wood character to the wine. If wood is used together with amphorae, the bigger Italian botti’s are preferred. It is especially popular using Italian cultivars in the same way the Romans used to do it. More cultivar aroma is retained in amphorae, which adds more freshness to the wine if it is bottled at an earlier stage. Winemakers usually focus on only one or two cultivars to ensure that the amphorae are utilised optimally. It can however be white or red cultivars and also in different styles. Wines, other than white or red Italian cultivars, which are already made in amphorae, include Sauvignon blanc, Chardonnay, Riesling, Viognier, white wines with skin contact known as orange wines, Pinot noir, Shiraz, Grenache, Cinsaut and Cabernet Sauvignon (Ness, 2016).
Ness, L., 2016. A new heyday for clay. Vineyard & Winery Management, March/April 2016: 58 – 62.