AWRI Dr Cristian Varela
The Australian Wine Research Institute
Strategies for reducing alcohol levels in wine Dr Cristian Varela Senior Research Scientist Darek Kutyna, Adrian Coulter, Keren Bindon, Richard Gawel, Creina Stockley, Richard Muhlack, Peter Dry, Leigh Francis, Markus Herderich, Sakkie Pretorius, Paul Henschke, Simon Schmidt, Anthony Borneman, Paul Chambers The Australian Wine Research Institute
Alcohol in Australian Wine
The Australian Wine Research Institute
31
Alcohol content (% v/v)
3A Average 14.2%
39 38
Ethanol
2 37 36
1 35 33 34 2 1 3217 3211 3225 3229 5444 5447 5441
Year
Why is alcohol increasing?
The Australian Wine Research Institute
Grape maturity enhances rich, ripe fruit flavour, and colour intensity. Decreases the unripe green and vegetal flavours. Greater maturity leads to higher sugar content. Higher sugar equals higher alcohol levels.
Why reduce alcohol?
The Australian Wine Research Institute
Too much!
123
143 153 163
789ABCDEFCB8B8
Alcohol abuse Stuck
Normal Wine & society
Sluggish
How to reduce alcohol?
The Australian Wine Research Institute
Viticultural practices Winemaking practices
Fermentation practices Post-fermentation technologies
Active research - examples •The Maturity Trial – sequential harvest
• Low-ethanol yeast
The Australian Wine Research Institute
The Maturity Trial: Does alcohol matter?
The Australian Wine Research Institute
Cabernet Sauvignon grapes Five harvesting times No malolactic fermentation Alcohol concentration from: 11.8 % v/v to 15.5 % v/v
Some sensory data - Palate attributes
The Australian Wine Research Institute
8B44 "3 "5 "6 "7 "8
7B84
7B44
6B84
6B44
5B84
5B44
3B84
3B44
4B84
4B44
CDEFF
FF
EF
"# E
FE FEE F!EF E
Consumer liking & alcohol content Consumer preference
Alcohol 15.5
16.0
7.0
a
14.0 11.8
12.0 10.0 8.0 H1 H2 H3 H4 H5
Harvest
ab
ab
b
13.6
Liking score
Concentration [%v/v]
The Australian Wine Research Institute
6.0
c
5.0 4.0 3.0 H1 H2 H3 H4 H5
Harvest
Harvesting earlier could deliver a wine that consumers prefer or like just as much and contains up to 2 %(v/v) less alcohol Caution: One trial – one variety – one vintage
Consumer segments
The Australian Wine Research Institute
7.5 7.0 6.5 6.0
H1 H2 H3 H4 H5
5.5 5.0 4.5 4.0 3.5 3.0
Cluster 1 (44%)
Cluster 2 (33%)
Cluster 3 (23%)
Low-ethanol yeast
The Australian Wine Research Institute
Genetically modified (GM) strain
Saccharomyces cerevisiae
Re-educated (non-GM) strain
Characterised and/or domesticated strain NonSaccharomyces (wild yeast)
Existing variation between strains
The Australian Wine Research Institute
13.2 13.0
0.1
0.1 0.2
0.2
Ethanol % (v/v)
12.8 12.6
0.5
12.4 12.2 12.0 11.8 N96
UCD522
EC1118
Maurivin B AWRI R2
AWRI796
Engineering wine yeast metabolism
SUGAR
The Australian Wine Research Institute
G6P
G3P
PYR
ACETATE
GLYCEROL
ETHANOL
Best GM low-alcohol yeasts
The Australian Wine Research Institute
AWRI1631 Ethanol 15.7 %(v/v) Glycerol 9 g/L Acetic acid 0.2 g/L
Wine yeast AWRI2531 Ethanol 13.3 %(v/v)
GM yeast
Glycerol 30 g/L Acetic acid 0.2 g/L
AWRI2532 Ethanol 12.2 %(v/v) Glycerol 40 g/L Acetic acid 0.5 g/L
GM yeast metabolism AWRI1631 15.7 %
The Australian Wine Research Institute
AWRI2531 13.3 % AWRI2532 12.2 %
ACETALDEHYDE
300
Acetoine [Fold difference] Acetoin [mg/L]
Acetaldehyde [mg/L] Acetaldehyde [mg/L]
ACETOIN
1200
350
250 200 150 100
800
400
50
0
0 AWRI1631 AWRI AWRI2532 AWRI AWRI AWRI2531
1631
2531
2532
AWRI1631 AWRI AWRI2532 AWRI AWRI AWRI2531
1631
2531
2532
The Australian Wine Yeast Systems Biology Consortium
The Australian Wine Research Institute
Pyruvate decarboxylase SUGAR
The Australian Wine Research Institute
ETHANOL
PYRUVATE
ACETALDEHYDE
ACETIC
PDC1 PCD5 ACETOIN
ACETALDEHYDE
ACETOIN
Non-GM approach
The Australian Wine Research Institute
Selective pressure that drives alcohol down
Cell growth Selection Breeding
Mutant yeast Screening of low alcohol phenotype
Low alcohol yeast
Wine yeast
Best pilot non-GM approach
3452
6789ABCC8D 1C8E9BFBCABC 3316
The Australian Wine Research Institute
Non-Saccharomyces strains • 50 Non-Saccharomyces strains • Sequential inoculation • Aerobic and anaerobic conditions
The Australian Wine Research Institute
Sequential inoculation
The Australian Wine Research Institute
S. cerevisiae
Non-Saccharomyces
S. cerevisiae
Best non-Saccharomyces strain
6789ABCC8D
The Australian Wine Research Institute
798
42 542
Summary
The Australian Wine Research Institute
• Holistic approach on how to reduce alcohol in wine. • Consumer study key to understand alcohol preferences. • GM low-alcohol yeasts fundamental for the development of non-GM strains. • Non-Saccharomyces strains show potential for alcohol reduction. !BC" 123342567839A
89 D789E
342
52
!BC"#$ 1BC3959DEAE29
542
5 2
342
554 2
4 2
Acknowledgments
The Australian Wine Research Institute
AWRI - ACAG Creina Stockley (IDS) Keren Bindon (Tannin group) Paul Henschke (Biosciences) Adrian Coulter (IDS) Richard Gawel (Biochemistry) Richard Muhlack (Industry Applications) Peter Dry (IDS) Leigh Francis (Sensory)
Low ethanol-team Chris Curtin Darek Kutyna Angela Contreras Claudio Hidalgo
Systems Biology Paul Chambers Anthony Borneman Simon Schmidt
AWRI Management Markus Herderich Sakkie Pretorius
Sensory team Helen Holt Patricia Osidacz
Acknowledgments
The Australian Wine Research Institute
Research at The AWRI is supported by Australia’s Grapegrowers and winemakers through their investment agency the Grape and Wine Research and Development Corporation, with matching funds from the Australian Government.
Strategies for reducing alcohol levels in wine Dr Cristian Varela Senior Research Scientist Darek Kutyna, Adrian Coulter, Keren Bindon, Richard Gawel, Creina Stockley, Richard Muhlack, Peter Dry, Leigh Francis, Markus Herderich, Sakkie Pretorius, Paul Henschke, Simon Schmidt, Anthony Borneman, Paul Chambers The Australian Wine Research Institute
Alcohol in Australian Wine
The Australian Wine Research Institute
31
Alcohol content (% v/v)
3A Average 14.2%
39 38
Ethanol
2 37 36
1 35 33 34 2 1 3217 3211 3225 3229 5444 5447 5441
Year
Why is alcohol increasing?
The Australian Wine Research Institute
Grape maturity enhances rich, ripe fruit flavour, and colour intensity. Decreases the unripe green and vegetal flavours. Greater maturity leads to higher sugar content. Higher sugar equals higher alcohol levels.
Why reduce alcohol?
The Australian Wine Research Institute
Too much!
123
143 153 163
789ABCDEFCB8B8
Alcohol abuse Stuck
Normal Wine & society
Sluggish
How to reduce alcohol?
The Australian Wine Research Institute
Viticultural practices Winemaking practices
Fermentation practices Post-fermentation technologies
Active research - examples •The Maturity Trial – sequential harvest
• Low-ethanol yeast
The Australian Wine Research Institute
The Maturity Trial: Does alcohol matter?
The Australian Wine Research Institute
Cabernet Sauvignon grapes Five harvesting times No malolactic fermentation Alcohol concentration from: 11.8 % v/v to 15.5 % v/v
Some sensory data - Palate attributes
The Australian Wine Research Institute
8B44 "3 "5 "6 "7 "8
7B84
7B44
6B84
6B44
5B84
5B44
3B84
3B44
4B84
4B44
CDEFF
FF
EF
"# E
FE FEE F!EF E
Consumer liking & alcohol content Consumer preference
Alcohol 15.5
16.0
7.0
a
14.0 11.8
12.0 10.0 8.0 H1 H2 H3 H4 H5
Harvest
ab
ab
b
13.6
Liking score
Concentration [%v/v]
The Australian Wine Research Institute
6.0
c
5.0 4.0 3.0 H1 H2 H3 H4 H5
Harvest
Harvesting earlier could deliver a wine that consumers prefer or like just as much and contains up to 2 %(v/v) less alcohol Caution: One trial – one variety – one vintage
Consumer segments
The Australian Wine Research Institute
7.5 7.0 6.5 6.0
H1 H2 H3 H4 H5
5.5 5.0 4.5 4.0 3.5 3.0
Cluster 1 (44%)
Cluster 2 (33%)
Cluster 3 (23%)
Low-ethanol yeast
The Australian Wine Research Institute
Genetically modified (GM) strain
Saccharomyces cerevisiae
Re-educated (non-GM) strain
Characterised and/or domesticated strain NonSaccharomyces (wild yeast)
Existing variation between strains
The Australian Wine Research Institute
13.2 13.0
0.1
0.1 0.2
0.2
Ethanol % (v/v)
12.8 12.6
0.5
12.4 12.2 12.0 11.8 N96
UCD522
EC1118
Maurivin B AWRI R2
AWRI796
Engineering wine yeast metabolism
SUGAR
The Australian Wine Research Institute
G6P
G3P
PYR
ACETATE
GLYCEROL
ETHANOL
Best GM low-alcohol yeasts
The Australian Wine Research Institute
AWRI1631 Ethanol 15.7 %(v/v) Glycerol 9 g/L Acetic acid 0.2 g/L
Wine yeast AWRI2531 Ethanol 13.3 %(v/v)
GM yeast
Glycerol 30 g/L Acetic acid 0.2 g/L
AWRI2532 Ethanol 12.2 %(v/v) Glycerol 40 g/L Acetic acid 0.5 g/L
GM yeast metabolism AWRI1631 15.7 %
The Australian Wine Research Institute
AWRI2531 13.3 % AWRI2532 12.2 %
ACETALDEHYDE
300
Acetoine [Fold difference] Acetoin [mg/L]
Acetaldehyde [mg/L] Acetaldehyde [mg/L]
ACETOIN
1200
350
250 200 150 100
800
400
50
0
0 AWRI1631 AWRI AWRI2532 AWRI AWRI AWRI2531
1631
2531
2532
AWRI1631 AWRI AWRI2532 AWRI AWRI AWRI2531
1631
2531
2532
The Australian Wine Yeast Systems Biology Consortium
The Australian Wine Research Institute
Pyruvate decarboxylase SUGAR
The Australian Wine Research Institute
ETHANOL
PYRUVATE
ACETALDEHYDE
ACETIC
PDC1 PCD5 ACETOIN
ACETALDEHYDE
ACETOIN
Non-GM approach
The Australian Wine Research Institute
Selective pressure that drives alcohol down
Cell growth Selection Breeding
Mutant yeast Screening of low alcohol phenotype
Low alcohol yeast
Wine yeast
Best pilot non-GM approach
3452
6789ABCC8D 1C8E9BFBCABC 3316
The Australian Wine Research Institute
Non-Saccharomyces strains • 50 Non-Saccharomyces strains • Sequential inoculation • Aerobic and anaerobic conditions
The Australian Wine Research Institute
Sequential inoculation
The Australian Wine Research Institute
S. cerevisiae
Non-Saccharomyces
S. cerevisiae
Best non-Saccharomyces strain
6789ABCC8D
The Australian Wine Research Institute
798
42 542
Summary
The Australian Wine Research Institute
• Holistic approach on how to reduce alcohol in wine. • Consumer study key to understand alcohol preferences. • GM low-alcohol yeasts fundamental for the development of non-GM strains. • Non-Saccharomyces strains show potential for alcohol reduction. !BC" 123342567839A
89 D789E
342
52
!BC"#$ 1BC3959DEAE29
542
5 2
342
554 2
4 2
Acknowledgments
The Australian Wine Research Institute
AWRI - ACAG Creina Stockley (IDS) Keren Bindon (Tannin group) Paul Henschke (Biosciences) Adrian Coulter (IDS) Richard Gawel (Biochemistry) Richard Muhlack (Industry Applications) Peter Dry (IDS) Leigh Francis (Sensory)
Low ethanol-team Chris Curtin Darek Kutyna Angela Contreras Claudio Hidalgo
Systems Biology Paul Chambers Anthony Borneman Simon Schmidt
AWRI Management Markus Herderich Sakkie Pretorius
Sensory team Helen Holt Patricia Osidacz
Acknowledgments
The Australian Wine Research Institute
Research at The AWRI is supported by Australia’s Grapegrowers and winemakers through their investment agency the Grape and Wine Research and Development Corporation, with matching funds from the Australian Government.
