Voltis
Also known as: ResDur 13
Voltis
Summary
Voltis is one of four PIWI varieties authorized for French AOC wines in 2021, marking a historic moment in French viticulture. This white variety, developed by INRA/IFV as part of the ResDur breeding program, produces neutral, clean wines ideally suited for distillation, particularly for Cognac production where it was first approved. The name “Voltis” evokes electricity and energy (from “volt”), reflecting modern sustainable viticulture. With approximately 150 hectares and expanding rapidly, Voltis represents France’s commitment to developing disease-resistant varieties that can be used in prestigious appellations while dramatically reducing chemical inputs.
Identity
VIVC: Entry #24729
Berry Color: BLANC
Type: PIWI (Interspecific hybrid)
Breeding Number: ResDur 13
Creator: INRA/IFV (Institut National de la Recherche Agronomique / Institut Français de la Vigne et du Vin)
Authorization: 2018 (variety protection); 2021 (AOC use)
Name Origin: From “volt” (electrical unit), suggesting energy and modernity
Genetic Origin
Parentage: Complex INRA ResDur breeding program
The ResDur (Résistance Durable) program creates varieties with:
- Multiple resistance genes (pyramided)
- Durable resistance (hard to overcome)
- Traditional wine quality
Breeding Goals:
- Very high disease resistance
- Neutral character suitable for Cognac
- High yields for distillation
- French wine quality standards
The ResDur Program
INRA’s ResDur program represents systematic PIWI development:
- Approach: Pyramid multiple resistance genes
- Strategy: Durable resistance that fungal pathogens cannot easily overcome
- Quality Focus: Match traditional variety wine quality
- Varieties: Floréal, Vidoc, Artaban, Voltis (first authorized batch)
Disease Resistance Profile
| Disease | Resistance Level | Notes |
|---|---|---|
| Downy Mildew | VERY HIGH | Multiple resistance genes |
| Powdery Mildew | HIGH | Strong resistance |
| Botrytis | MEDIUM | Some susceptibility |
| Black Rot | HIGH | Good resistance |
Spray Reduction: 80-95% reduction vs. traditional varieties
Durability: Pyramided resistance genes make breakdown less likely
Historic French Authorization
The 2021 authorization was groundbreaking:
Four ResDur Varieties Authorized
| Variety | Color | Character |
|---|---|---|
| Floréal | White | Aromatic, Sauvignon-like |
| Voltis | White | Neutral, distillation |
| Artaban | Red | Fruity |
| Vidoc | Red | Structured |
Authorization Terms
- Maximum 5% of vineyard area initially
- Maximum 10% of blend
- Must be labeled as “variété résistante”
- Monitored trial period
Distribution
Total Global Plantings: ~150 hectares (rapidly expanding)
| Country | Hectares | Notes |
|---|---|---|
| France (Cognac region) | ~120 | Primary focus |
| Germany | ~20 | Quality wines |
| Other | ~10 | Trial plantings |
Growth Trend: Rapid expansion in Cognac region
Viticulture
Growth Characteristics
- Vigor: Medium to high
- Growth Habit: Semi-erect
- Budbreak: Medium
- Flowering: Mid-season
- Véraison: Medium
- Harvest: Medium
Climate Requirements
- Ideal Climate: Maritime to continental
- Heat Summation: 1,400-1,800 GDD
- Versatility: Adapted to traditional French wine regions
- Frost: Moderate tolerance
Soil Preferences
- Cognac Region: Chalk and limestone soils
- Adaptable: Various French wine soils
- Effect: Soil influences acidity and neutrality
Viticultural Management
- Training: Guyot (standard for Cognac)
- Pruning: Standard practices
- Yield: High yields acceptable for distillation
- Spray Program: MINIMAL—key advantage
Enology
Must Parameters at Harvest
| Parameter | Typical Range | Notes |
|---|---|---|
| Brix | 19-22° | Moderate (for Cognac) |
| pH | 3.0-3.3 | Low (ideal for distillation) |
| Titratable Acidity | 7.0-10.0 g/L | High |
| YAN | 150-220 mg/L | Variable |
Character
- Profile: NEUTRAL (key characteristic)
- Purpose: Ideal canvas for distillation
- Comparison: Similar to Ugni Blanc (traditional Cognac grape)
Fermentation
- Yeast Selection: Neutral strains
- Temperature: 16-20°C
- Duration: 10-14 days
- Character: Clean, fermentation aromas minimal
Primary Use: Distillation
Voltis is optimized for Cognac production:
- High Acidity: Essential for distillation
- Neutral Character: Clean spirit base
- Yield: High yields acceptable
- Quality: Matches Ugni Blanc for eaux-de-vie
Table Wine Production
When made as table wine:
- Light, neutral character
- Citrus notes, clean
- High acidity
- Blending component
Sensory Profile
As Table Wine
| Category | Descriptors |
|---|---|
| Visual | Pale, green hints |
| Aromatic | Neutral, subtle citrus |
| Palate | Light, high acidity, clean |
Key Characteristic
NEUTRALITY—Voltis is not meant to be aromatic or distinctive; its value lies in its clean, neutral character ideal for distillation.
Winemaker Considerations
Challenges
- Neutral Character: Limited interest for varietal wine
- Market Position: Distillation-focused
- Blend Limits: AOC restrictions on percentage
- Consumer Education: Explaining PIWI concept
- Terroir Expression: Limited
Opportunities
- Cognac Production: Ideal replacement for traditional varieties
- Sustainability: Dramatic spray reduction
- Historic Precedent: First PIWI for French AOC
- Cost Reduction: Lower production costs
- Environmental Impact: Reduced chemical use
Winemaking Tips
- Treat like Ugni Blanc for Cognac production
- High acidity is beneficial—preserve it
- Neutral character is the goal
- For table wine: blend with aromatic varieties
Cognac Context
Traditional Cognac Grapes
- Ugni Blanc: ~98% of plantings
- Colombard: Minor
- Folle Blanche: Minor
Voltis in Cognac
- First PIWI authorized for Cognac
- Can reduce spray program dramatically
- Matches Ugni Blanc quality for distillation
- Limited to 10% of blend initially
Comparison with Traditional Distillation Grapes
| Characteristic | Voltis | Ugni Blanc | Colombard |
|---|---|---|---|
| Character | Neutral | Neutral | Slightly aromatic |
| Acidity | Very High | Very High | High |
| Disease Resistance | Excellent | Poor | Moderate |
| Spray Requirements | Minimal | Full program | Moderate |
| Cognac Use | Authorized | Primary | Authorized |
The Future of French PIWI
Voltis represents the beginning of PIWI in French AOC:
- Proves sustainable viticulture possible in prestigious regions
- Opens door for other PIWI varieties
- Demonstrates French commitment to environmental responsibility
- Models approach for other wine regions globally
Sources
- VIVC Database - Vitis International Variety Catalogue
- INAO (Institut National de l’Origine et de la Qualité)
- IFV (Institut Français de la Vigne et du Vin)
- BNIC (Bureau National Interprofessionnel du Cognac)
- ResDur Program publications
Last Updated: January 13, 2026