Wine has a long tradition in the Gres family in the region of Rhein-Hessian Appenheim. Since the mid-1600s vines have been harvested and processed with a devotion to wine in this family business. Klaus Gres has worked at companies in South Africa and California until he set up his own operation ten years ago. With the help of his parents and wife, the winemaker produces around 120.000 bottles of wine a year.
Thus far, the Gres family has won 14 honour awards of the state in the Rhine region for their wines. There were already some top ratings in the Gault Millau as well! In the Trotec interview he speaks about developments in wine production, traditional methods and the use of air dehumidifiers in his wine cellar. The devices from the TTK S series from Trotec are an indispensable aid. His most recent purchase is a model from the luxury class: the DH 30 VPR.
Mr Gres, a wine thrives on the interaction of climate, soil and the intuitive flair of the winemaker. How do you approach your production?
Of course, the microclimates of the vineyard, the vine and the soil play a significant role in the quality of the wine. But the work of a winemaker is at least just as crucial. The winemaker must perfectly process the grapes he has picked perfectly throughout the year. This begins with a careful pressing. Then comes the fermentation and the ageing of the wine. The storage must have the optimal conditions to be able to achieve the perfect wine. As such nothing should be left to chance.
The development of the wines, particularly red wines, is of central importance. What do you pay attention to here?
After the fermentation some white wines, but above all red wines, are bottled in the small oak barrels in which they will develop. Of course you can be satisfied with the given climatic conditions in the wine cellar or you can optimize those conditions. But when your result isn’t optimal you should reconsider your approach. I learned early on that the air humidity in a wine cellar plays an important role for the quality of the wine. Therefore, I have begun to fine-tune this.
How did you hit on the fact that the regulation of air humidity could be the key to success?
I have worked as a winemaker in California and in South Africa. There the oak barrels are often stored in halls above ground. There I got to know wonderfully complex full-bodied red wines. When working in local wineries I had always asked myself why I had to regularly refill the barrels with so much wine during storage – unlike our production done with traditional wooden barrels. I realised that the level of air humidity was much lower there than here, and that the alcohol did not evaporate in storage but rather the smaller water molecules escaped through the wood of the barrels. The complexity of a wine is produced by exactly this reduction and the associated water evaporation from the wine. From that I knew that in our cellars in Appenheim I would have to carefully regulate the air humidity with devices in order to achieve a similar quality.
Does that mean that you support employing traditional methods today through the use of modern solutions?
We are the training enterprise for winemakers-to-be and mix classic and modern wine ageing methods. Apprentices must always attend to the development stage of a wine as part of their training. Previously very modern vinified wines were taken on by the trainees such as, for example, the Sauvignon blanc. With the development of this wine, the grapes are cooled with dry ice and the musts fermented with carefully chosen selected yeasts at set temperatures. Obviously these are also great wines. But these are also wines highly pruned to a special taste.
Whereas we produce most wines without a particular technique, above all the top wines. Today, the students are deciding more and more to take on these classic wines and are surprised by the superior results that are achieved.
What does production look like without a technique?
We do a traditional must fermentation – sometimes even in wooden vats where it still has to be mashed by hand. The wine is extracted from the mush for up to two months. Then it is pressed and goes into a wooden barrel, where it is stored for up to three years. And this is at a certain humidity so that it develops complexity. Here our wines are all made vegan. Besides clay, which we need for protein stabilization, we don’t use any finings. But with the climate technology in the wine cellar we are relying on a cutting edge solution.
How exactly do you control the climate?
For me an air dehumidifier is actually like a wine press, a device a wine producer should certainly have. Indeed, not only is the development of the wines supported. Through the use of dehumidifiers condensation is also eliminated, and for purposes of labelling the bottles are kept dry so that the labels stay stuck on. In the wine cellar we have the TTK 140 S from Trotec in use, for the labelling we have the TTK 100 S. We also have temperature-controlled stainless steel tanks in which the wines are fermented. Thus we can set the appropriate fermentation temperature for every wine. By regulating the temperature and humidity we create the optimal climate conditions for wine-making.
What is, then, the optimum air humidity for your wines?
There’s no one formula for that. With red wines the crucial point is the storage. With Merlot and Cabernet in particular we need high evaporation. For this the air humidity should be under 60 percent. Then we have optimal evaporation. If it were over that, then the water could not so easily or could even not at all dissipate into the air. If we went to a room humidity of below 60 percent, then there could be problems with the barrels. Then the wood would dry up.
You use quite a few dehumidifiers from Trotec in your wine cellar. How did you come across these models?
I searched on the Internet for the market leader in this area and thus encountered the equipment from Trotec. I have tried them and I have noticed that my devices provide very good service. Even my first instrument, the TTK 140 S, which has already been running for more than 20,000 hours, is still in use. The air is aggressive in a wine cellar, because we’re also working with sulphurous acid here. That’s an extreme environment for the equipment. What’s more, their use is only intermittent. At times they run continuously for three months, then don’t again for some time. Thus far the dehumidifiers haven’t failed me. That is crucial. It’s like in the wine industry: The quality must be good enough and the price-performance ratio too, of course – then people stick with their products. And that’s why I have now bought myself another Trotec dehumidifier: the DH 30 VPR. It’s practical, attached to the wall and ensures our optimal production.
Mr Gres, many thanks for this informative interview. We wish you continued success with your wines.
Ingelheimer Straße 6