The history of winemaking processes dates back thousands of years. Now, scientists at the French Academy of Agricultural Sciences have successfully challenged traditional methods by introducing modern new technologies. Alfalaval's decanter centrifuges play an important role.

In the past few decades, wineries around the world have been striving to improve product quality and increase the efficiency of production processes, and technology has become increasingly important. The era of barefoot treading grapes is gone, replaced by various mechanical equipment such as crushers, blenders and decanter centrifuges. In the Languedoc region of southern France, the Pech Rouge test site of the French Academy of Agricultural Sciences (INRA) is experimenting with new techniques and processes to challenge the traditional habits of winemaking.

New technologies can improve the winemaking process, so there is no constant process or technology. “The uniqueness of wine is that it varies with grape variety, soil characteristics and vintage years,” said Jean-Louis Escudier, director of the Pech Rouge test site at the French Academy of Agricultural Sciences. “So what we can do, It is to evaluate any special processes that may be used and what they can achieve.” This is the mission of the Pech Rouge base. It works with industry colleagues to evaluate how new processes can improve winemaking and to identify strategies for product development.

Among the many patented red wine manufacturing processes in the French Academy of Agricultural Sciences, there is a process called “instant release”. Ten years ago, it was identified as an alternative to the traditional pre-fermentation impregnation process. In the traditional process, tannins, colorants and aroma components are leached from the grape skin and grape seeds into the grape pulp. This traditional process takes two weeks. The “instant release” process heats the grapes to 70-95 ° C in a few minutes and then immediately cools them in a vacuum vessel. This will break the cell wall of the grape and increase the amount of phenolic compound it releases by about 50%. These phenolic compounds can affect the taste, color and taste of the wine.

Many wineries have adopted a heated extraction process, but the French Academy of Agricultural Sciences has found that the rapid cooling of grapes can produce special effects using the “instant release” process. The “Instant Release” technology has been successfully applied in many wineries in France and has been introduced to other countries, including Australia.

After the "instant release" process, it is customary to use the peel to make juice, producing wines that contain tannins and can be preserved for a long time. Recently, however, the French Academy of Agricultural Sciences has been considering the fermentation of grape pulp without peel, thus eliminating the pressing process. In this way, there is no need for secondary extraction, and the resulting wine is lighter, more fruity and more fashionable.

“Using the patented “instant release” process of the French Academy of Agricultural Sciences, the rapid cooling rate of the grapes can produce special effects. In this process, a decanter centrifuge is used instead of the traditional pressing process to extract and clarify the grape pulp. A faster and easier way to produce wine of the same quality."

“The wine produced by this process has a rounded mouthfeel and a rich fruity aroma, which is very suitable for modern drinking. So we started to consider a decanter centrifuge instead of the traditional pressing process to extract and clarify the grape pulp. Whether it will bring other benefits." Escudier. To do this research, the French Academy of Agricultural Sciences partnered with Alfa Laval to introduce the Foodec decanter centrifuge into the process.

In this study, grape juice, grape skins, and grape seeds were added to a blender after an instant release process to slowly produce a homogeneous liquid. The clarified grape juice is then separated from the grape skin and grape seed by a decanter centrifuge, eliminating the need for a pressing and clarification process.
The initial test showed encouraging results. With a decanter centrifuge, it seems that a wine of at least the same quality can be produced in a faster and easier way.

Alain Samson, an engineer at the French Academy of Agricultural Sciences, said that they have compared the extraction and clarification effects of using a decanter centrifuge with the effects of using conventional processes. “We also compared the pulp of our own Syrah and Grenache grape varieties with the pulp of the grape varieties of the two major cooperative farms Merlot and CabernetFranc in the region,” he added. “So there are a lot of variables. ”

Wine is produced in exactly the same fermentation process in a single temperature controlled barrel. Then, before the taste of the French Academy of Agricultural Sciences, a set of tests was conducted to compare the results. “Preliminary sensory evaluations show that this new process produces wines that are comparable to those made with the original extraction and clarification process, which is a very good news,” Samson said.
If the final test results are as positive as the original findings, then this potential advantage will be extremely important for winemakers. “Using such a streamlined production system not only saves winemakers time and money,” Samson said, “and in the process, there is no need to use any environmentally unfriendly additives.” Traditional clarification methods generally require Additives such as perlite, pyrite and white gelatin are used. These additives are no longer used in the process, which means that after the process is finished, the cost of processing the additives is saved.

Because the decanter centrifuge can also be used in other processes, such as clarifying distiller's grains and removing sediment, it also creates additional economic benefits. “The process is suitable for larger wineries with more infrastructure budgets,” explains Samson. “For some hand-brewed wines, this process may not yield anything, but for high-yield wineries. That said, it does streamline the process without sacrificing product quality."