Understanding yeast to prevent hydrogen sulfide (H 2 S) in wine. Enlightened science Empowered artistry. Matthew Dahabieh, PhD

Transcription

1 Understanding yeast to prevent hydrogen sulfide (H 2 S) in wine Enlightened science Empowered artistry Matthew Dahabieh, PhD

2 Volatile sulfur compounds

3 Viticulture Aging Fermentation Sources of H 2 S

4 Fermentation

5 Alcohols x2

6 Oxidation O 2 Loss of aroma Cu Limited efficacy Loss of flavour

7 Sulfate S-amino acids Yeast sulfur metabolism

8 SO 2 SSU1 SO 2 Nitrogen Sulfur metabolism MET3 MET14 MET16 MET10 MET5 (amino acids) MET17 Cysteine STR1 STR4 SO 4 2- SO 3 Homocysteine SUL1,2 MET6 Methionine Wine Yeast

9 Excess H 2 S (enters wine) Nitrogen (amino acids) MET17 Sulfite MET6 S-containing (SO 3 ) MET10 STR1 amino acids MET5 STR4 *Rate limited Sulfite reductase (MET10)

10 Evolution s solution Yeast from Lambrusco grape must Emilia Romagna, Italy UCD932 Met More efficient sulfur usage

11 Met10 DNA Amino acid Charge H 2 S C Threonine UCD932 A Lysine

12 No released H 2 S No excess SO 2 Nitrogen (amino acids) MET MET17 Sulfite MET5 MET6 S-containing (SO 3 ) STR1 amino acids Altered kinetics Increased affinity STR4 *Rate limited Sulfite reductase (MET10-932)

13 Turning a Clean specialist into a generalist Sparkling Sweet Red Dry UCD932 White Still Aromatic

14 x Yeast mating: making hybrids

15 a cell (Haploid) Shmoo formation (Haploid) Cell contact (Haploid) a factor α factor α cell (Haploid) Mating Sporulation Hybrid strain (Diploid) Karyogamy (Diploid) Cell fusion

16 Haploid Shmoo Cell Hybrid Karyogamy cell pair formation fusion budding

17 Classical breeding GMO

18 + 1st cross UCD932 x + 50% UCD932 50% Strain A

19 + 2nd cross x + 25% UCD932 75% Strain A

20 + 3rd cross x + 13% UCD932 87% Strain A

21 + 4th cross x + 6% UCD932 94% Strain A

22 + UCD932 x 50% UCD932 1st cross 50% Strain A + x x % UCD932 2nd cross 75% Strain A x x Nth cross + x x + 0.5% UCD932 Final cross 99.5% Strain A + +

23 SO 2 Selection characteristics

24 H 2 S production BiGGY Lead acetate

25 SO 2 Selection characteristics

26 H 2 S-preventing yeast Commercial strain #1 Commercial strain #2 Commercial strain #3 250 Reducing sugars (g/l) Fermentation kinetics Days Chardonnay grape must (YAN 364 mg/l, free SO 2 5 ppm, Brix 21.3)

27 SO 2 Selection characteristics

28 Total SO 2 (ppm) 75 SO SO 2 production 0 Must H 2 S-preventing yeast Commercial strain #1 Chardonnay grape must (YAN 293 mg/l, free SO ppm, Brix 22.4)

29 SO 2 Selection characteristics

30 Gustative harmony Pleasantness Typicality Olfactory intensity Floral 2 Bitterness 0 Apple Sensory H 2 S-preventing yeast Acidity Mature fruits Commercial strain #1 Commercial strain #2 Commercial strain #3 Olfactory balance Bread Honey Prosecco Méthode Champenoise

31 Enlightened science Empowered artistry Vivace Allegro Andante Maestoso Brioso Ossia ORGANIC H 2 S-Preventing Yeast Developed by Classical Breeding H 2 S-Preventing Yeast Developed by Classical Breeding H 2 S-Preventing Yeast Developed by Classical Breeding H 2 S-Preventing Yeast Developed by Classical Breeding H 2 S-Preventing Yeast Developed by Classical Breeding H 2 S-Preventing Yeast Developed by Classical Breeding 500 g 500 g 500 g 500 g 500 g 500 g Enlightened science Empowered artistry Enlightened science Empowered artistry Enlightened science Empowered artistry Enlightened science Empowered artistry Enlightened science Empowered artistry Enlightened science Empowered artistry

32 H 2 S-Preventing Yeast Comparison RECOMMENDED VARIETALS SPECIES H 2 S PREVENTION O GMO ORGANIC NON-GMO INOCULATION RATE FERMENTATION TEMPO TEMPERATURE RANGE ALCOHOL TOLERANCE COMPETITIVE FACTOR NITROGEN REQUIREMENTS FOAM PRODUCTION GLUTEN FREE Vivace Chard. Pinot Gris Fruit wine S. cerevisiae bayanus g/l mod-fast C (59-86 F) 16% active low-med low RY Vintage 2015 Allegro Andante Sauv. Blanc Chard. Geuwertz. Cab. Sauv. Zinfandel Sangiovese S. cerevisiae bayanus S. cerevisiae g/l g/l moderate moderate C (59-82 F) C (59-95 F) 16% 17% active neutral medium medium low low RY Vintage 2015 Merlot Maestoso C 9 Zinfandel S. cerevisiae g/l moderate 16% neutral high low 10 Cab. Franc (59-88 F) Brioso Pinot Noir S. cerevisiae g/l moderate C (59-86 F) 16% neutral medium low Ossia ORGANIC White wine Red wine Fruit wine S. cerevisiae hybrid g/l moderate C (61-86 F) 16% active medium low Enlightened science Empowered artistry

33 Winemaking without worry. Take the Renaissance Challenge. Spicy, smooth, intense Andante RECOMMENDED VARIETALS Cab. Sauvignon Zinfandel Syrah Sangiovese H 2 S-Preventing Yeast Developed by Classical Breeding 500 g GMO H 2 S PREVENTION NON-GMO SPECIES Enlightened science Empowered artistry S. cerevisiae Compare Renaissance Yeast to your favorite wine yeast and see for yourself the quality difference that Renaissance Yeast H 2 S-preventing strains can make for your wine! Enlightened science Empowered artistry

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