selecting yeasts for cabernet sauvignon

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Selecting yeasts to match styles of Wines Outline My concentration is towards Cabernet sauvignon Important attributes Yeast strain characteristics Fermentation styles. Popular Yeasts for Cabernet Sauvignon Interview with Adam Hazeldine of Babich Wines, NZ Siyamalan Subramanian [email protected]

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This presentation gives a better picture on selection of yeasts to match different styles of CS wine. In general, it aids to give information on various yeast strains for Cabernet Sauvignon Wine-Making

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Selecting yeasts to match styles of Wines

• Outline

– My concentration is towards Cabernet sauvignon

– Important attributes

– Yeast strain characteristics

– Fermentation styles.

– Popular Yeasts for Cabernet Sauvignon

– Interview with Adam Hazeldine of Babich Wines, NZ

Siyamalan [email protected]

Selecting yeasts to match style of Cabernet Sauvignon

• Cabernet Sauvignon is a red grape variety grown throughout the world. It is the

undisputed king of red grapes, and not only as a result of its fabulous popularity as

the central grape in Bordeaux.

• Cabernet Sauvignon is a hardy, versatile grape, perfectly suited to producing

powerful, lustrous red wines that can age for decades and continually get better.

• Cabernet Sauvignon, once the most widely planted red, now plays second fiddle to

pinot noir in New Zealand

• In New Zealand, Merlot often dominates Cabernet sauvignon. Merlot-based wines

usually have medium body with hints of berry, plum, and currant.

• Its softness and "fleshiness", combined with its earlier ripening, makes Merlot a

popular grape for blending with the sterner, later-ripening Cabernet Sauvignon,

which tends to be higher in tannin.

Important Attributes

• Cabernet Sauvignon is strongly influenced by ripeness of the grapes at

harvest. Unripe fruit gives wine with high pyrazines and exhibit green bell

peppers and vegetal flavour and overripe grape gives wine with aromas of

black currants.

• New Zealand’s Cabernet Sauvignon was marked with aggressive green and

vegetal flavors. The grape is blended with Merlot to help compensate for

climate and terroir.

• Consideration should be given on selection of yeast strains based on thier

effect on colour pigments.

– In a research on selection of yeast strains for Cabernet Sauvignon, among

Saccharomyces cerevisiae and Saccharomyces bayanus yeast S.bayanus wine

used to exhibit greater wine colour density and lower Grape anthocyanin

concentration than in S.cerevisiae wines

– This is due to the formation of stable pyranoanthocyanins and pigmented

polymers enhanced by S. bayanus yeast

(Hayasaka, Birse, Eglinton, & Herderich, 2007)

Yeast Strain Characteristics

• In a research, Saccharomyces cerevisiae strains (1EV, 2EV and 7EV) has

been studied in musts derived from Cabernet Sauvignon and Tempranillo.

– The anthocyanin, pyranoanthocyanin and non-anthocyanin phenolic content,

and color characteristics of the resulting wines have been compared to those of

a commercial strain.

– It was found that Anthocyanins were the compounds most influenced by the

yeast strain

(Maria Monagas, 2007).

• Selection should be also based on their parietal adsorption activity which

can enhance wine quality and safety. Based on winemaking requirements

and on parietal adsorption activity, a specific selection of wine yeasts might

be performed:

– to protect wine color during red winemaking,

– to selectively remove ochratoxin A, and

– to protect phenolic compounds responsible for antioxidant activity.

(Caridi, 2007).

Yeast Strain Characteristics (Contd.)

• Several strains may be blended and used in parallel to attain all the yeast

characteristics.

• Selection should be based on the yeast strain's fermentation characteristics

such as:

1. Rate of fermentation

Several yeast strains are known as vigorous fermentors. Short fermentation time is

need in most cases as wine is protected by alcohol more quickly, thus limiting the

spoilage of wine by other microorganisms

2. Alcohol Tolerance

A yeast strain is usually considered to be Alcohol-tolerant when it can ferment to

final alcohols higher than 15 percent Alcohol. And used for fruits with high brix

3. SO2 and Cold tolerance

Cabernet Sauvignons used to undergo an extended "cold-soak“. Ability to ferment

at low temperatures would minimize the transition time needed to initiate

fermentation at the end of the cold-soak.

4. Nutrient requirements and other characteristics such as Malolactic

compatibility, H2S production and VA production

• In addition the yeast strain's fermentation products should be considered

– ester producing• Ester-producing yeast strains are not generally used in Cabernet Sauvignon

production.

– glycerol producing• Glycerol-producing yeast strains can make wines with a "broader" mouthfeel and

longer finish, making the CS seem richer and silkier

– polysaccharide producing• Polysaccharides can contribute to mid-palate and texture of the wine. Like glycerol,

increasing the polysaccharides makes a CS seem richer.

– mannoprotein producing• mannoproteins contribute to the overall mouth and fullness of the finished wine.

They also seem to have the effect of harmonizing the overall taste of the wine on the palate.

– having high ß-glucosidase activity• The enzyme ß-glucosidase releases glucose-bound flavorants into the solution.

– degrades malic acid • Some yeast strains like Lallemand 71B and Maurivin Primeur, can metabolize L-

Malic Acid. This reduces the TA and raises the pH of the final wine without producing the buttery, diacetyl flavors associated with conventional, bacterial malolactic fermentations

Yeast Strain Characteristics (Contd.)

Fermentation Styles

• Classic Style

– This is my term for those Cabernet Sauvignons that are made in the historic

Bordeaux or Claret style. The style can be defined by lower sugar levels and general

ripeness

• New world Style

– Here the fruit will be more ripe and the wine will be more alcoholic and full bodied.

• Easy Drinking style

– The fruit will be more ripe and the light pressing will be given, and contact time in

skin is much reduced, so the wine will be less tannic.

• New Zealand’s Cabernet Sauvignon

– The wines will exhibit black currant elements and wines will bear green herbal

flavors even with extended aging.

– It is often blended with Merlot to bring down the herbal flavour and to soften the

harsh tannins.

Commercial Yeast strains for CS

Lalvin Bourgovin RC 212

Desired for full tannin and colour stabilization, Temp 15-30 C, Alcohol tolerance 14%,

Rate moderate, high nutrient requirements, more ML compatibility, Gives Tannic red;

Light young Red wine.

Enoferm BDX

Minimizes colour loss; enhances flavours & aromas, Temp 15-30, Alcohol tolerance 15,

Rate moderate, high nutrient requirements

Lalvin ICV – D21

Inhibits development of cooked-jam & burning sensation in highly mature concentrated

Cabernet Sauvignon

Lalvin ICV – GRE

Muse with short skin contact regiments to reduce vegetal & undesirable sulfur

components

Red Star

• Pastuer Red (Davis #904)– Desired for varietal fruit flavours & complex aromas, Temp 18-30 C, Alcohol tolerance 16%, Rate

fast, normal nutrient requirements, more ML compatibility, Gives Tannic red; Light young Red wine.

• Montrachet (Davis #522)– Desired for full bodied intense colour reds, Temp 15-30 C, Alcohol tolerance 13%, Rate fast, normal

nutrient requirements, more ML compatibility, Gives Tannic red wine.

• Pastuer Champagne (Davis #595)– Desired for dry light reds, Temp 15-30 C, Alcohol tolerance 13-15%, Rate fast, normal nutrient

requirements, more ML compatibility,

White Labs

– Merlot Red (WLP740)

– Desired for reds that must ferment to dryness, Temp 10-32 C, Alcohol tolerance 17%, Rates low to moderate, normal nutrient requirements, more ML compatibility, Gives light young red; Tannic red wine.

– French Red (WLP750)

– Desired classic Bordeaux, Temp 16-32 C, Alcohol tolerance 17%, Rate slow to moderate, normal nutrient requirements, more ML compatibility, Gives light young red; Tannic red wine

Wyeast

– Chateau Red (4028)

– Desired for easy drinking reds, Temp 15-32 C, Alcohol tolerance 14%, Rate slow to moderate, normal nutrient requirements, more ML compatibility, Gives light young red; Tannic red wine

– Bordeaux (4267)

– Desired for High sugar musts rich intense berry, Bordeaux style reds, Temp 13-32 C, Alcohol tolerance 14%, Rate slow to moderate, normal nutrient requirements, more ML compatibility, Gives light young red; Tannic red wine

Interview with Winemaker “Adam hazeldine” of Babich Wines, New Zealand

• Adam Hazeldine was Head Winemaker at Babich

Wines since 2001.

• Babich wines is one among the few wineries in New

Zealand to make Cabernet Sauvignon dominated

Cabernet-Merlot blend.

Style for Cabernet Sauvignon

• Style for Cabernet Sauvignon in Babich wines is in-between Classic and new world style. The grapes are harvested at 25 Brix.

• They used to add Enoferm BDX and wild yeasts is used in combination in some cases

• In NZ, Merlot dominates cabernet sauvignon, while in all over the world the usual blend ratio is CS:M, 70:30

• But in Babich wines, 100 % Cabernet sauvignon and often CS dominated merlot blends are made. They used to go for free run and then hard press, followed by individual fermentation. Then the wines are blended with desired ratio. And they never go for cold soaking before fermentation.

• Similar fermentation techniques for fermentation of both Merlot & Cabernet Sauvignon including yeast strains were used in Babich Wines

(contd..)

For yeast selection following are the parameters considered for Cabernet sauvignon winemaking.

1. Fermentation temperature range

• 31 C for Juice with 24 Brix, and 28 C for juice with higher brix

2. Alcohol tolerance

• 12.5 to 14 is Babich wines’CS Alcohol range

3. Rate of fermentation

• Moderate

4. Malolactic compatibility,

• More ML compatibility

5. Nutrient requirement

• CS for Babich grows on gravels and pebbles and DAP added to meet the nutrient requirements.

Summary

• Cabernet Sauvignon, once the most widely planted red, now plays second

fiddle to Pinot Noir. But still New Zealand’s Cabernet Sauvignon is unique

among the world producers with a style in between Classic and New

World.

• Selection of yeast strain plays a major role in retention and stability of

color pigments, parietal adsorption activity and for unique style of Cabernet

Sauvignon and Merlot.