Minimally processed food and beverage production is becoming a major priority in food science, driven by growing consumer demand for natural products free from synthetic additives, preservatives, and allergens. In winemaking, this movement has fueled the rise of “natural wine”—a low-intervention approach that presents both unique sensory possibilities and complex technical challenges.
Speaking to the Athens-Macedonian News Agency (ANA-MPA), Dr. Yiannis Giavasis, Associate Professor of Food Microbiology at the University of Thessaly, detailed the findings of the three-year BioWineries research initiative (2023–2025). The project explored chemical-free and sulfite-free winemaking techniques utilizing indigenous yeasts and plant-derived antioxidants.
The science of low-intervention winemaking
While the term “natural wine” is not legally defined by official certifying bodies, it broadly refers to wines produced with minimal intervention: no synthetic chemical additives, no added sulfites (the conventional preservative and antioxidant used in winemaking), and no commercial starter yeast cultures (Saccharomyces cerevisiae).
Instead, natural winemaking relies entirely on the wild microbiome of the grape and the winery environment. “While this carries a higher risk of fermentation failure, it ultimately yields distinctive wines that more accurately reflect the sensory profile of the grape and the unique terroir of the region,” Giavasis explained.
Key study findings from BioWineries project on natural wine in Greece
The research project, funded by the European Agricultural Fund for Rural Development and the Greek Ministry of Agricultural Development and Food, was conducted by the University of Thessaly. Focusing on the indigenous Limniona and Malagouzia grape varieties, the team isolated local microflora and tested natural plant extracts to prevent oxidation without sulfites. Key takeaways from the study include:
- Dominance of Indigenous Yeasts: Despite an initial presence of diverse environmental bacteria and wild yeasts on raw grapes, alcohol-tolerant native strains of Saccharomyces cerevisiae and beneficial lactic acid bacteria (Oenococcus) naturally established dominance in the maturing wine, supplying it with unique local characteristics that commercial strains cannot replicate.
- Natural Antioxidant Substitutes: Tests using grape pomace powder, pomegranate peel, and olive fruit extract showed promising results. Olive extract contributed to high alcohol yields, low volatile acidity, a deeper red color, and enhanced body. Pomegranate peel delivered the most positive impact on flavor, aroma, and finish. Combined, these extracts provided effective antioxidant protection capable of replacing sulfites.
- Spoilage Indicators & Vessel Selection: The team identified Lentilactobacillus parafarraginis as a key early-stage spoilage indicator in wines with off-flavors. Additionally, fermentation in traditional clay amphorae encouraged beneficial micro-oxygenation and Oenococcus growth compared to stainless steel tanks, which retained higher levels of unwanted Lactobacillus.
A competitive edge for boutique wineries
“Producing high-quality natural wine is entirely feasible when the growth of indigenous Saccharomyces cerevisiae strains is paired with natural antioxidants and strict monitoring against spoilage organisms,” concluded Giavasis.
He highlighted that the approach in the study provides a strategic advantage for small wineries in Greece, allowing them to leverage authentic, local terroir in the production of natural wine rather than competing with mass-produced, standardized global wines.
Related: Top Ten Greek Wines
See all the latest news from Greece and the world at Greekreporter.com. Contact our newsroom to report an update or send your story, photos and videos. Follow GR on Google News and subscribe here to our daily email!
