Varieties and Clones

Question 1

Past Exam Questions

Answer 1

2017: Discuss which vine varieties would be most suitable for the production of dessert wines. Explain your choice with specific reference to any climatic requirements.
2016: Can Cabernet Sauvignon and Riesling be successful in the same location?
2015: Which are the most suitable grape varieties for the production of high quality traditional method sparkling wines and why?
2014: How can viticultural and winemaking techniques influence aromatic compounds in wine? Refer to wines made from Riesling, Sauvignon Blanc, and Pinot Noir.
2013: You are tasked with establishing new vineyard sites to produce Chardonnay in Casablanca, in Chile, and in Champagne. What would be your major concerns?
2004: Examine the reasons for clonal selection, the alternatives, and all the relevant quality considerations.
2000: Why are some grape varieties more successful than others in certain vineyard environments? Discuss the principles involved and give examples from both hemispheres.
1997: The selection of plant material for a vineyard will have an impact on the wine produced from it. Consider the options open to a viticulturist. What views do you have with regard to clones?
1995: Riesling is grown in different locations with a variety of results. Explain this with reference to Germany, France, and either California or Australia.

1993: Write brief notes on the following and discuss in relation to vineyard location.
- Dolcetto
- Furmint
- Mazuelo
- Mourvedre
- Petit Manseng
- Pinotage
- Rkatsiteli
- Tibouren
- Verdelho
- Viura

1991: Discuss the relative importance of grape variety and terroir. How’s the balance of their influence affected by weather in a given year?

Question 2

Sparkling varieties

Answer 2

early ripening ideal so you can have good flavor development at low Brix?

Question 3

Aromatic compounds

Answer 3

• Temperature is a key factor in formation
• In Riesling, too much sun on fruit, also water stress, and warm soils, results in petrol.
  (Petrol = TDN = 1,1,6 - Trimethyl - 1,2 dihydronapthalene)
• In Sauvignon Blanc, the primary aromatic compounds are MPs, Methylpyrazines**

Note: water can plump berries affecting ratios of compounds

Question 4

Dessert wines

Answer 4

Criteria for dessert varieties:
- thick skins
- rate of sugar accumulation
- acidity
- aromatic compound levels
- loose clusters good for healthy dried grapes
…..important to consider humidity levels and production method
….must consider all methods: fortified, dried fruit, botrytis, late harvest, etc

• Muscat Blanc a Petits Grains = smaller berries, has good acid, high terpene levels despite ripeness, so therefore aromatic freshness is retained even if berries are dried

DRIED GRAPE WINES: berries are actually very vulnerable during drying. Want healthy grapes, no botrytis. Best way to achieve this is through ventilation. Grapes with loose clusters have the advantage here

LATE HARVEST WINES: to avoid botrytis, need wind, so you can have a later harvest without disease pressure. Thicker skins have advantage here.

ICE WINE: Riesling and Vidal good choices here. High acid, highly aromatic, cold hardy.

VENDAGE TARDIVE: less botrytis than SGN. Gewurztraminer often too low acid. Pinot Gris is best of both world – flesh and juicy.

FORTIFIED: these grapes are able to get super ripe. Rich in polyphenols. Touriga Sensesa (sp?) makes the most elegant style of Port.

Question 5

Examples

Answer 5

• TUSCANY: Avignonesi makes a Vin Santo called Occhio di Pernice. For this, they use a clone of Sangiovese that has loose clusters (same clone as in Vino Nobile)
• AMARONE: loose cluster clone of Corvina is really important to Amarone
• FONDILLON: made from inland Alicate, arid with sandy intensely drained soils. Monastrell good here in that it is late ripening

MAJOR BOTRYTIS GRAPES:

• Sauvignon Blanc
• Muscadelle
• Semillon (esp as when super ripe skins get thin)
• Riesling
• Furmint
• Chenin Blanc

Question 6

Cabernet Sauvignon / Riesling Question

Answer 6

Per Greg Jones, Cabernet likes average growing season temps of 61 - 68F and Riesling has the widest range of noble vinifeira, from 55.5 - 63.5.
So there is limited crossover

EXAMPLE:
Smith-Madrone, varies by aspect

Question 7

Clones

Answer 7

• Pax believes that clones only matter in young vines

EXAMPLE:
- 115 in CA is super light and floral, but in OR is dense and less acidic

Question 8

Quick notes on varieties RE site selection

Answer 8

Dolcetto: Richer, more fertile flat land of Piedmont. Early-ripening so planted in cooler, higher sites

Furmint: Highly prized, best slopes, highest humidity

Mazuelo: AKA Carignan, vigorous and late-ripening so in hot sites

Mourvedre: likes it hot, but also sensitive to drought, low yields, bush vines

Petit Manseng: late-ripening, vigorous, high-acid, so can handle heat a la Virginia

Pinotage: bred in 1925, historically in hot, flat areas but now creeping up the slopes and quality is improving

Rkatsiteli: high sugar and high acid and very cold hardy. Successful in Georgia and Finger Lakes

Tibouren: AKA Rossesse. Disease-resistant, South France and Liguria

Verdelho: very early ripening, drought tolerant - CA and Australia

Viura: AKA Macabeo. low acid, thick skinned, late ripening, sensitive to wind. Spain’s most widely planted white variety.