In a recent LinkedIn post, Magali Blank, Director of the State Education & Research Institute for Viticulture and Pomology (LVWO Weinsberg), described a summary of the Institute’s article, “Sustainable White Wine Production,” published in the journal Deutsche Weinbau (issue 04/2026, pp. 24–29).
Blank writes:
“Together with M. Freund (Geisenheim University), I investigated the central question within the framework of the ATW project (Committee for Technology in Viticulture, project no. 218): Can aroma-preserving and energy-saving fermentation really be achieved simultaneously? Based on seven trials, four vintages, and three grape varieties, our answer is: Yes.
The article provides a comprehensive overview of the project – from the energy calculations for fermentation cooling, to the summary aroma assessment.
Fermentation temperature: the underestimated energy factor
An increase in the fermentation temperature of just 5 °C (e.g., from 14 to 19 °C) can reduce the required cooling capacity by a factor of 3.6. That sounds tempting – but at the same time, up to 80% of the volatile aroma compounds can escape with the fermentation CO₂ at higher temperatures.
AromaLoc™ – membrane-based aroma recovery
In this project, we tested the AromaLoc™ system (distributed by JUCLAS): a silicone membrane (PDMS) that separates volatile aroma compounds directly from the fermentation gas, and returns them to the headspace of the tank – where they dissolve back into the wine. Can aroma recovery increase the fermentation temperature – and save energy at the same time, without compromising sensory quality?
Results
️Comparison: T22°C with AromaLoc™ vs. T18°C, without recirculation → +26% — +37% [total aroma gain with AromaLoc, despite the higher fermentation temperature] → 40% – 93% cooling energy savings, depending on tank size, insulation, and starting temperature → No significant loss of quality. [This was] confirmed by triangular tests across all trial years.
AromaLoc™ – economic assessment
Implementation requires a separate unit for each tank, which entails corresponding investments. [NB: Frequently it is possible to deploy the same AromaLoc machine across multiple fermentation tanks during a single season — this is the experience of many wineries using the AromaLoc system].
A more in-depth analysis of the [AromaLoc] system – including its membrane technology, aroma selectivity, and economic assessment – will be published soon in Der Winzer (The Winemaker).
Read the full article now in “Deutsche Weinbau” (German Viticulture), 04/2026. A heartfelt thank you to the team at the experimental cellar of the LVWO Weinsberg and Geisenheim University for the excellent collaboration!”
