Over the years, winemakers have adopted a variety of commercially available microorganisms to control different aspects of fermentation. This has allowed for more consistent and manageable results, but as the wine industry evolves, new challenges and opportunities emerge. Today, consumer demand for sustainability is pushing winemakers to find ways to reduce their environmental footprint. One innovative yet underexplored approach is leveraging specific microorganisms to make winemaking more eco-friendly.
Beyond the vineyard: Sustainability in the winery
Traditionally, sustainability in viticulture focused on reducing the use of pesticides, fertilisers, and heavy metals in the vineyard. However, recent research shows that the environmental impact of wine also hinges on the winemaking process itself, particularly the microbial transformations that occur during fermentation.
New insights into fermentation temperature have revealed opportunities for reducing winemaking’s carbon footprint. Refrigeration systems consume the biggest percentage of a winery’s electricity. These systems are vital for controlling fermentation temperature, stabilising wines, and storing finished wines. In white and rosé wine production, temperature control is critical to maintaining quality but also comes with a hefty energy cost.
The energy-saving potential of fermentation
Recent studies highlight that a more nuanced approach to fermentation temperature management can save significant energy without sacrificing wine quality. Traditionally, lower fermentation temperatures were believed to be key to producing rich aromas. However, new research reveals that this isn’t always the case. It depends on the strain of yeast used and the specific conditions of fermentation.
Many winemaking experiments have shown that carefully raising the fermentation temperature by just a few degrees can yield impressive energy savings. For example, in a 2016 study, Chardonnay for sparkling wine was fermented at 19°C instead of the standard 15°C. This slight increase slashed energy use by 65% without affecting the wine’s chemical composition or sensory characteristics. Similar studies in Germany on Riesling wines found energy savings of up to 70% by raising fermentation temperatures by 5°C, again without compromising quality.
Building on these findings, larger-scale trials have been conducted to confirm the energy-saving potential across different grape varieties.
Significance of these studies
The results from these studies provide ideas for winemakers to cut energy costs in the cellar. Winemakers are encouraged to do fermentation trials (in collaboration with their yeast suppliers) at slightly higher temperatures. Winemakers can also consider doing trials with yeasts they have not used before that perform optimally (fermentation viability and aroma production) at higher fermentation temperatures (e.g., at 17°C instead of 13°C).
Reference
Nardi, T. (2024). Energy saving in winemaking: the role of microorganisms and the potential of careful fermentation management. Infowine: https://www.infowine.com/en/energy-saving-in-winemaking-the-role-of-microorganisms-and-the-potential-of-judicious-fermentation-management/
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