The advantages of using the qvevri

            Although the benefits of making and storing wine in a qvevri have never been fully understood or comprehensively studied, we believe the subject is highly significant for traditional Georgian winemaking. We address three key techniques of vinification:

·      achieving a natural temperature balance in the qvevri;

·      wine fermentation and aging;

·      removing tartar from qvevri wine.  

Winemaking in factory conditions that require chemical additives to render a desired stability and clarity to the wine is very different from the traditional methods using the qvevri and marani (Traditional Georgian wine cellar).  The latter process is natural and requires no chemical agents, provided that the qvevri and marani themselves are made and arranged according to standards.

            The primary benefit of using the qvevri is that the wine varies only a few degrees in winter and summer. The optimal temperature for wine storage and maintenance is naturally maintained in a qvevri, while under factory winemaking conditions temperatures have to be maintained by costly equipment.

Temperature plays a key role not only when storing wine but also during fermentation. As a rule, the exterior of a qvevri is treated with lime wash and the outside walls of large-size qvevri are covered with limestone. The lime-treated walls of a qvevri preserve wine at temperatures higher than the ambient temperature, which results in alcoholic fermentation, and lasts for a longer time than for non-limed qvevri. Qvevri walls can hold a stable temperature as long as necessary for malo-lactic, or secondary fermentation, as it is frequently called. Under household conditions, this fermentation continues for about a month. Malo-lactic fermentation plays a special role in making red wines, and is important for white wines as well, especially more astringent ones. The content of malic acid in the wine diminishes and the wine acquires certain gustatory qualities, completeness and perfection--its unpleasant high acidity disappears.  The process of removing tartaric acid (tartrates) from the wine also serves to reduce acidity.  We return to this subject as a process in winemaking.

            In qvevri-winemaking, the second and one of the most important processes is the fermentation and aging.  Qvevri not only stores the wine well but actually contributes to the processes of fermentation and aging better than other vessels do. The opinion of some winemakers today that the qvevri does not contribute to fermentation and aging is ungrounded and erroneous.

            In making a Kakhetian- or Imeretian-type wine in a qvevri, all processes are carried out chronologically and naturally which, under factory conditions, require different techniques and chemical additives.

Under factory conditions the alcoholic fermentation in steel tanks is often accompanied by using European yeast culture.  We believe that with these technologies, Georgian or European wines take on a uniform character and, as a rough comparison resemble bottled soda that is very similar all over the world, irrespective of where they are bottled. Such wines are almost completely devoid of any unique character.

            Wine produced using the qvevri is characterized by its unique type, stability, high potential for aging, natural brilliance, distinguished flavor and aroma, high tannin content, and other positive properties. Maintaining wine in qvevri with a natural temperature balance and optimal fermentation temperature makes European yeasts unnecessary. Even in the case of Kakhetian-type white wines, the wine can frequently stay on the pomace until early spring.

One might wonder how such wine avoids the negative effects of the lees, or grape sediment. The answer is found in the very specific shape of the qvevri: the bottom of a qvevri is a particular form of pointed cone. At the end of fermentation, most grape seeds separate from the skins and sink to accumulate in the bottom of the vessel. 

This process is further facilitated by mixing the pomace. Under the effect of pressure, the grape seeds in the bottom of the vessel are covered by the lees which--under heavy pressure-- cause the seeds to be separated from the wine. After fermentation has completed the grape skins remain floating on the surface under the effect of carbon dioxide inside the skins, while the lees sink to the bottom. Thus the wine itself remains in contact only with the skins and extracts a maximum of substances that are beneficial for human health. It is reputed that Kakhetian-type white wines contain many more beneficial substances than European pomace-free fermented wines. The fact that qvevri-made wines are naturally stable and do not require the addition of any chemical agents for stabilization is illustrated by Kakhetian wines, for example, which are rich in tannins.  These are known for their ability to bind wine proteins that would otherwise make the wine turbid. Therefore, Kakhetian wines are not prone to such wine turbidity, which explains the natural stability and brilliance of these wines.

The completion of fermentation usually coincides with a gradual decrease in the ambient temperature and cold weather.  This favorably influences wine clarification and the removal of tartrates. Removing tartrates from wine in ancient times was carried out differently than today.  In old fragments of qvevri walls very finely crushed pieces of flint have been found as admixtures (also found are other admixtures that have not been studied in terms of winemaking technology).  These presumably were used for the removal of tartrates from wine, which requires cold weather, as well as other effective techniques sometimes applied in wineries. In particular, tartrates were washed in alcohol and ground, then added to wine.  As a result, both the added tartrates and those naturally available in wine are then extracted. Since silicon is a high quality crystal and wine is in constant contact with it while in qvevris, this may produce the same effect as the addition of tartrates to wine. In addition to this, silicon in the qvevri walls reinforces the strength of the qvevri itself.

Tartrates are also removed from wine by alcohol formation.  Qvevri wines, and specifically Kakhetian-type ones have a high alcohol content which naturally facilitates the removal of tartrates.             

            Thus, the qvevri is a phenomenal vessel both in its form and content! Even today, all the processes and impacts of the qvevri on wine have not been studied completely. Qvevris do not receive the attention they deserve, even in Georgia, although their value is being increasingly recognized in Europe, where they are increasingly imported.   Qvevri wine exported from Georgia to Italy or to other countries is erroneously known as “amphora wine”.  However it would be advisable to preserve the qvevri name on Georgian labels with the inscription “qvevri wine”, and explain the meaning of “qvevri” on the back label.