Originally published on Nexus Azeo · Original text restored in full
The sun was just breaking over the rolling hills of Burgundy, casting a golden glow across the neatly lined vineyards. Jean-Pierre, a fifth-generation winemaker, stood among the vines, his hands brushing against the leaves still wet with morning dew. He remembered his grandfather’s stories of vintages long past, tales of balanced wines that danced on the palate with vibrant acidity. Yet, the grapes before him told a different story. The summers were hotter now, the harvests earlier, and the challenge to preserve that hallmark acidity had become his daily battle.
“How will we preserve this?” he wondered, gazing at the fruit that ripened faster with each passing year. This question, echoing across vineyards worldwide, underscores the challenges facing winemakers as they strive to maintain the delicate balance of acidity that defines their wines.
The Impact of Climate Change on Acidity
The rapid pace of climate change is upending the traditional frameworks of winemaking. Rising global temperatures lead to faster grape ripening, which directly impacts acidity. As grapes mature, their natural malic acid—a key contributor to wine’s sharpness—declines. This results in wines that are fuller-bodied, higher in alcohol, but often lack the crisp, lively edge that defines many iconic styles.
Take Burgundy, for instance. Known for its elegant, acid-driven Pinot Noir and Chardonnay, the region is already experiencing harvests up to three weeks earlier than in previous decades. This accelerates the sugar accumulation in grapes, resulting in wines that risk becoming flabby without careful intervention. Similarly, in Germany, the hallmark brightness of Riesling is under threat as warmer seasons push sugar levels up and acid levels down, forcing winemakers to adapt their centuries-old practices.
Innovations to Preserve Acidity
Faced with these changes, winemakers are turning to a mix of traditional wisdom and innovative techniques to safeguard acidity. These strategies span the vineyard, the cellar, and the selection of grape varieties themselves.
Vineyard Practices
Earlier Harvesting: Picking grapes earlier in the season is one of the most effective ways to preserve acidity. Bordeaux winemakers, for instance, are increasingly harvesting before peak ripeness to capture the natural freshness of their fruit. This approach, while necessary, must be balanced with the risk of underdeveloped flavours.
Relocating Vineyards: Many producers are moving to higher altitudes or cooler microclimates to escape rising temperatures. In Tuscany, vineyards are climbing the Apennine slopes, where cooler nights help preserve acid levels in Sangiovese grapes.
Canopy Management: By adjusting vine canopies to limit sunlight exposure, winemakers can slow sugar accumulation and maintain acid retention. This technique is particularly common in regions like Napa Valley, where heat stress is an increasing concern.
Soil Management: Enhancing soil health through biodiversity and organic practices can improve the resilience of vines and their ability to maintain acidity. Cover crops and composting are becoming essential tools in regions facing rising temperatures.
Varietal Selection
Certain grape varieties naturally retain higher acidity even in warmer climates. Producers are experimenting with these as a way to combat the effects of climate change:
Assyrtiko (Greece): This grape thrives in hot, dry conditions while maintaining bright acidity, making it a strong candidate for warmer regions.
Nero d’Avola (Italy): Known for its balance of rich flavours and acidity, this variety is gaining popularity in both its native Sicily and other Mediterranean climates.
Albarino (Spain): With its natural acidity and resistance to heat, Albarino is increasingly being planted outside Spain, including in the New World.
Hybrid Varieties: Crossbreeding traditional varieties with climate-resilient species offers new avenues for maintaining acidity. These hybrids are gaining attention in research vineyards worldwide.
Technological Interventions
Acidification: Adding tartaric acid during winemaking is a common practice in warm regions. While not new, this method is becoming more refined, with winemakers striving for integration that feels natural rather than forced.
Malolactic Fermentation Management: By controlling this secondary fermentation, winemakers can retain sharper malic acid in white wines or convert it to softer lactic acid in reds, depending on the desired style.
Precision Tools: Advanced technologies like cation exchange and electrodialysis are being employed to fine-tune acidity in wines post-fermentation without compromising their balance.
Cooling Systems: Sophisticated temperature control during fermentation and storage is helping preserve acidity by slowing down chemical reactions that lead to acid loss.
Regional Case Studies
Germany: Riesling Under Pressure
Traditionally reliant on cool climates to create its iconic, acid-driven Rieslings, Germany is now experimenting with innovative techniques to maintain freshness. Blending wines from cooler vintages, increasing shade in vineyards, and adopting partial fermentation methods are helping producers retain the hallmark zesty quality of their wines.
England: The Unexpected Star
The English wine industry, once dismissed due to its historically cold and wet climate, is thriving as temperatures rise. The chalky soils of regions like Sussex and Kent mirror those of Champagne, allowing for the production of sparkling wines with razor-sharp acidity. Producers have embraced this opportunity, carving out a new identity for English wine. Increased investment in vineyards and research facilities is positioning England as a leader in crafting high-acid wines.
Mediterranean Regions: A Shift in Focus
Southern Italy and Spain, long accustomed to warm conditions, are finding renewed purpose in their indigenous grape varieties. Nero d’Avola, Vermentino, and other Mediterranean varieties are proving resilient in retaining acidity despite intense heat, offering a roadmap for adaptation in hotter climates worldwide. These regions are also exploring shade management and drought-tolerant rootstocks to combat extreme conditions.
The Role of Acidity in Future Wine Styles
As winemakers continue to adapt, the very definition of wine styles may evolve. Burgundy’s crisp, mineral-driven whites may soften into rounder, less acid-forward expressions, while Bordeaux’s blends could incorporate Mediterranean varieties to maintain balance. New regions, from Patagonia to Scandinavia, may rise to prominence as their cooler climates become assets rather than hindrances.
Simultaneously, consumers will need to adjust their palates. Educating drinkers about the role of acidity—not just as a marker of freshness but as a critical component of balance and ageability—will be vital. As preferences shift, winemakers will have greater freedom to innovate, creating styles that honour tradition while embracing the realities of a changing world.
A Reflection on Acidity’s Timeless Importance
Acidity is more than a technical element; it is the essence of vibrancy in wine, the spark that brings balance and life to the glass. Over the next 30 years, its preservation will require ingenuity, courage, and a deep respect for the land. As climates change and traditions evolve, the commitment to acidity will remain a testament to winemaking’s enduring artistry, ensuring that each bottle continues to tell a story of place, time, and human endeavour. The future of wine, though uncertain, will be defined by the industry’s ability to adapt while preserving the heart and soul of this ancient craft.