Challenges and Opportunities in a Changing Climate & Christian E. Butzke 2 nd Vice President ASEV Enology Professor Purdue University butzke@purdue.edu 1.765.494.6500 enology.butzke.com
Outline Vintage-to-Vintage variation Flexibility in practices/regulations Grape/must temperature Yeast nutrient content Ripeness assessment Color extraction/copigmentation (Seed) tannin extraction Alcohol/aroma adjustments Aging/shipping temperatures
Wine Quality Grapes 75% Equipment 10% Barrels 10% Winemaker 5% Thomas Eddy, 2000 In: Wine Marketing University Press
World Viticulture 50ºF 50º 68ºF 0º 68ºF 50ºF 50º
Latitude Comparison France 42 IN PA CA 32 South Africa
Latitude Comparison 42 IN PA Iberia CA 32
Iberia
Regional Warming/Cooling ºC 30 25 20 15 10 5 +/- 6C Almeria Barcelona Burgos 0 ENE FEB MAR ABR MAY JUN JUL AGO SET OCT NOV DIC
Regional Warming/Cooling T ( F) 102 Annual Temperature Fluctuation Oakville, Napa Valley 92 82 72 62 6C 52 42 32 J J F M A M J J A S O N D
California Degree Days (55ºF) 6000 5500 5000 4500 4000 3500 3000 Central Valley North Coast Central Coast '90 '91 '92 '93 '94 '95 '96 '97 '98 '99 Vintage
California Degree Days (55+ºF) North Coast 4500 4300 4100 3900 Wine Quality Scores 3700 3500 3300 '90 '91 '92 '93 '94 '95 '96 Vintage
Artificial Neural Networks Clone Rootstock Weather Soil Type Vine Spacing Irrigation Fertilizer Pest Control Yield Management Viticulture Dr. David Block Grape Juice Characteristics Yeast/Bacteria Characteristics Processing Parameters A N N Fermentation Kinetics Chemical Analysis Sensory Analysis
Grape Growing Conditions and Vintage Quality Scores Neural Network Fit Quality Score Model Fit R = 0.77 (p < 0.001) Vintage Year D. Block, UC Davis
Flexible Practices/Regulations Irrigation Varietals Aging Requirements
Vineyard/Varietal Match Full color/tannin ripeness ripening too-early ideal ripening late ripening Full aroma ripeness ripening too late Y. Glories 1986
Ripeness Variation/Assessment
@ Veraison = @ Harvest Ripeness Variation R. Boulton, UC Davis
Brix 20.0-21.1 21.1-22.1 22.1-23.0 23.0-24.9 Range: 20.0-24.9 Mean: 22.1 +/- 0.9 Ripeness Variation R. Boulton, UC Davis
Fruit/Must Chilling
Fruit/Must Chilling Skin Contact Time = f (Temperature)
Yeast Available Nitrogen Content NH 4 + Variation by Varietal and Region CA, OR, WA Amino
Yeast Available Nitrogen Content Deficiency Variation by Varietal 0 Juices < 140 mg N/L (%) 10 20 30 40 50 Pinot noir Zinfandel Merlot Cabernet Sauvignon Cabernet franc Chardonnay Sauvignon blanc
Nitrogen & élevage sur lies Fermentation Temperature = f (Fermentation Rate) Fermentation Rate = f (Yeast Available Nitrogen) Lees => Mannoproteins = f (Yeast Available Nitrogen)!
New Diseases? Glassy Winged Sharp Shooter Xylella fastidiosa (bacterium) Pierce s Disease Dying Grapevines
Wine and Regional Cooling www.clivar.org
Annual Precipitation Average Regional Variation
Gulf Stream Effect Precipitation Variation Long Island, New York October rain: Average 94 mm 2005 305 mm Gulf Stream
Rain at Harvest No sun Water on clusters Water in soil Berry splitting High humidity Suspended ripening Dilution, Rot Dilution Rot Rot
Cold Maceration/Fermentation Timing Skin Contact Time = f (Temperature)
Red Wine Color Extraction vs. Stability Anthocyanins Berry: 100% in skin 0% in seeds 0% in pulp Dr. Roger Boulton Wine: 25% Cabernet 15% Pinot Noir
Copigmentation Anthocyanin Copigment Stack Cofactor Anthocyanin
Color and Cofermentation Pinot Noir/Pinot? Syrah/Viognier? Sangiovese/Trebbiano? Photo: Wine Spectator
Cap Management Technique Does it matter?
Anthocyanin vs. Tannin Extraction Anthocyanins (g/l) Tannins (g/l/6.25) Seed Tannin Skin contact time (days) P. Ribereau-Gayon
Seed Number per Berry Variation by Vineyard Sample Seed Number 2 1.9 1.8 1.7 1.6 1.5 1.4 1.3 1.2 1.1 1 11-Sep 18-Sep 25-Sep 2-Oct 9-Oct 16-Oct Date +30% seed tannin
Seed Number per Berry Variation/Ripeness = f (Vintage) +30% seed tannin J. Kennedy, ORSU
Tannin Management Maceration of wine on the pomace after fermentation is through, increases tannin but adds nothing to color. Prof. Eugene Hilgard University of California Berkeley, 1887
Polymeric Color Monterey Sonoma Paso Robles Lodi Heat at the End Rotary/Enzyme Extended Maceration Oak Tannins Control 0 2 4 6 8 HPLC Absorbance A. Waterhouse
Maceration = f (Temperature) Cap Management
Extraction and Temperature Extractable Phenolics (%) 100 80 30 C 20 C 10 C 60 40 Temperature 20 0 0 200 400 Skin Contact Time (hours)
Extraction and Alcohol Extractable Phenolics (%) 100 80 60 40 20 Ethanol (%vol) 14 11 8 4 2 0 0 0 200 400 Skin Contact Time (hours)
Shiraz Shrivel Dehydration, Sugar and Alcohol
Alcohol Removal?
Reverse Osmosis Aroma Removal Molecular Weights: Ethyldecadienoate 196 Oak Lactone 156 Vanillin 152 4-Ethylphenol 122 2-Phenylethanol 122 Methoxypyrazine 110 Ethylacetate 88 Diacetyl 86 Molecular SO 2 64 Acetic acid 60 Ethanol 46 CO 2 44 Water 18
Wine Shipping Heat Exposure en Route Temperature ( F) 120 110 100 90 80 70 60 ( pp / / / / )
-08-16 -08-17 -08-17 -08-07 -08-07 -08-08 -08-08 -08-09 -08-09 -08-09 -08-10 -08-10 -08-11 -08-11 -08-12 -08-12 -08-12 -08-13 -08-13 -08-14 -08-14 -08-15 -08-15 -08-16 -08-16 100 95 90 85 80 75 70 65 60 Wine Shipping Container Position Top Tail Nose Temperature ( F)
Barrel/Bottle Aging Reactions O 2 uptake: (Ribereau-Gayon 1933) Doubling of Rate 3.8ºC Browning: (Berg & Akiyoshi 1956) SO 2 decline (W): (Ough 1985) EC formation: (CEB 2001) 7.8ºC 37ºC 16ºC
Winemaking Advice Always question your traditions Be flexible with vineyard/wine regulations Watch similar international regions Invest money in wine and grape research Extend and use scientific information Be out in the vineyard Cold-store wines for comparison
Winemaking Advice Save money to replant, buy equipment Be pro-active don t wait too long Watch your yeast nutrient status Don t over-extract before/after fermentation Measure your seed numbers Don t believe in miracle cures/equipment Use intuition and intellect
Wine Quality Grapes 75% = Climate! Equipment 10% Barrels 10% Winemaker 5%
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Portland OR June 17 th
enology.butzke.com
Enology Session Sigrid Gertsen-Briand & Christian Butzke