2025-01-03
A recent study published on Thursday, January 2, in the scientific journal OENO One examines how grape ripeness and harvest timing affect the chemical composition, foam properties, and sensory attributes of sparkling wines made from the Greek native variety Savvatiano. Conducted by a team from the Agricultural University of Athens, the research focused on the impact of grape maturity on sparkling wine produced using the traditional method, or méthode champenoise, which involves a second fermentation in the bottle and extended aging. The study is particularly relevant as global demand for sparkling wine has grown steadily over the past few decades.
Savvatiano is the most widely planted white grape in Greece, especially in the Attica region and other parts of central Greece. Historically, it has been used primarily to produce retsina, a traditional wine flavored with pine resin, and white table wines with moderate aromatic profiles. Within the Greek market, Savvatiano has not been regarded as a noble variety compared to more expressive native grapes. However, modern viticulture and winemaking techniques have allowed the variety to showcase new qualities, producing dry wines with good acidity, citrus and tropical aromas, and notable aging potential. These evolving characteristics have prompted researchers to explore its suitability for sparkling wine production, a growing market segment in Greece and beyond.
The study took place over two harvest seasons, in 2019 and 2020, at a commercial vineyard in the Valley of the Muses in the Viotia region, north of Athens. The vines, planted more than 60 years ago, are grown in deep soils and managed without irrigation according to local agricultural practices. Grapes were harvested at three different ripeness levels based on their Brix value, which measures soluble solids: early, intermediate, and late. Each batch was transported to the university's enology lab, where the base wine was made and then transformed into sparkling wine using the traditional method. The resulting wines were aged in the bottle for 15 months before undergoing chemical and sensory analysis.
Harvest timing and grape maturity levels were found to be critical factors in the final quality of the sparkling wine, directly influencing acidity, alcohol content, and foam properties. Wines made from early-harvested grapes showed higher acidity and lower alcohol content, contributing to a more stable and persistent foam. This foam stability is highly valued by consumers, as it significantly impacts the perception of sparkling wines. Chemical analyses revealed that early-harvest wines contained higher concentrations of organic acids, such as tartaric and malic acids, resulting in a fresher sensory profile with dominant notes of green apple and citrus.
In contrast, wines made from late-harvested grapes had higher alcohol content, which negatively impacted foam stability. These wines exhibited more complex aromatic profiles with pronounced tropical notes and a longer finish. However, this complexity came at the cost of the freshness and balance found in early-harvest wines. Sensory evaluations by a tasting panel confirmed these distinctions. Early-harvest wines were rated as fresher and more balanced, with intense citrus and green apple aromas, while late-harvest wines stood out for their tropical aromas and mouthfeel intensity, though with less impressive foam quality.
The study also analyzed volatile compounds, which play a key role in the wine's aroma. It identified and quantified alcohols, esters, acids, and terpenes. Early-harvest wines showed higher concentrations of terpenes like linalool and nerol, which are responsible for floral aromas. Meanwhile, late-harvest wines contained more esters and acetates, which contribute fruity aromas. These compounds are produced during fermentation, and their concentration varies depending on grape maturity and winemaking conditions. Esters and acetates were primarily associated with tropical fruit aromas, more prominent in late-harvest wines.
Another key aspect studied was the foam formation and retention capacity of the sparkling wines. Researchers measured the maximum height and stability of the foam after injecting carbon dioxide into the wines. Results indicated that early-harvest wines had better foam formation and stability, while wines made from more mature grapes had less persistent foam. The presence of compounds such as organic acids and polysaccharides, released during fermentation and aging, contributed to the superior foam properties in early-harvest wines.
Organic acids also played a significant role in the sensory perception of the wines. The study showed that tartaric and malic acid levels decreased as grapes ripened, while pH levels rose, resulting in lower perceived acidity in late-harvest wines. Wines made from early-harvest grapes stood out for their acidity and fresh aromatic profile, qualities that tasting panelists associated with greater freshness and harmony.
The study concluded that grape ripeness at harvest is a major determinant of the aromatic profile and foam properties of Savvatiano sparkling wines. Early-harvest wines were characterized by fresher, citrus-driven aromas, higher acidity, and more stable foam, while late-harvest wines offered more tropical aromas and a longer finish but less foam quality. These findings are relevant for winemakers seeking to optimize their harvest practices to enhance the quality of their sparkling wines and meet consumer preferences.
The analysis underscored Savvatiano's significant potential for producing high-quality sparkling wines. Traditionally used for table wines and retsina, the variety's ability to produce sparkling wines with desirable foam properties and balanced aromatic profiles makes it a promising option for producers looking to diversify their offerings. In a context of climate change, where rising temperatures accelerate grape ripening, producers could benefit from harvesting Savvatiano earlier to preserve freshness and acidity in their sparkling wines. The study provides a solid scientific foundation for exploring new sparkling wine production opportunities in Greece by leveraging native varieties like Savvatiano instead of relying solely on international grapes like Chardonnay or Pinot Noir. This approach could help producers stand out in a competitive market and capitalize on growing consumer interest in sparkling wines made from local varieties.
Founded in 2007, Vinetur® is a registered trademark of VGSC S.L. with a long history in the wine industry.
VGSC, S.L. with VAT number B70255591 is a spanish company legally registered in the Commercial Register of the city of Santiago de Compostela, with registration number: Bulletin 181, Reference 356049 in Volume 13, Page 107, Section 6, Sheet 45028, Entry 2.
Email: [email protected]
Headquarters and offices located in Vilagarcia de Arousa, Spain.