White and Sweet Winemaking Flashcards
Explain the Skin contact options in white winemaking
No skin contact
- grapes are crushed and free run juice is separated of, and remaining grape mass is sent to press
or
- Whole bunches of uncrushed grapes are genly press to reduce risk of oxidation
Short period of skin contact
- increase flavour intensity, texure
- at a cool temperature to inhibit fermentation and only for a few hours
Extend period of skin contact or ferment with skin
- called orange wines or amber wines
- traditional in georgia, slovenia, friuli venezia giulia
- tannins are perceptible and flavours of dried fruits, dried herbs, hay and nuts
What are the techniques to clarify press juice before fermentation of white wine ?
Same techniques as pre-bottling
- settling
- centrifugation
- fining
- filtration
Why the freshly pressed grape juice must be clarified before fermentation ?
- Freshly pressed grape juice contains fragments of cells from grape skins and pulp
- If fermented untreated, unpleaseant aromas can form and fermentation may stop
some producers keep small amount of fragements, though to make the wine less susceptible to oxidtion. Still a risk of off-flavours forming. Rarely used for pure varietal character wine.
What is the optimum temperature for white wine fermentation ?
Between 12° and 22°
What is the effect of a too low or too high fermentation temperature ?
Too low : results in creation of pear drop aromas, failing to capture varietal fruit characters
Too high : Encourage more complex, non-fruit aromas, but risk of losing varietal fruit characteristics
What are the fermentation vessels options for white wines and how are they managing temperature?
Stainless steel vessels
- often have temperature control mechanisms
Barrels
- no easy to control tempeartures by their small size are normally housed in cool cellar to dissipate heat effectively.
- Higher end of the temperature range
What are the three choices a winemaker faces post-fermentation ?
- matured in oak or inert vessels with or without oak staves/chips
- use of fine lees
- allow or block malolactic conversion
Explain blending in white winemaking ?
May improve consistency, enhance balance and create a certain style
Many are pure primary fruit and role of blending is to ensure consistency.
non-aromatic varities may want to use varying amounts of lees contac, MLC and oak blend on different batches, to achieve more complexity.
Explain clarification and stabilisation in white winemaking
Improve clarity and sstability of the wine
White wines make sediment more apparent
Wines with residual sugar are at risk from microbiological infection, and winemaker might want to sterile filter the wine.
Explain the general high-volume inexpensive white wines
- Simple wines, not designed to mature in bottle,
- Easier to blend than to produce single varietal
- Labelled Dry white or Fruity white
- Neutral flavour and restraint appeal to wide range of consumers
- Choice of grape easy to ripen, acidity can be corrected in the winery
- Unoaked styles or oakes styles
- residual sugar to make them more palatable
- Vigorous nature to make high-volume
What are the three examples of High volume inexpensie white wines. Describe their styles.
Chardonnay
- Restraint
- easy to ripen in warm climates
- unoaked with peach an melon aromas
- Oak with vanilla and toast aroma
- Residual sugar
Pinot Grigio
- Restraint
- Easy to ripen in warm climates
- made in unoaked style
- pear drop aromas and flavours
- light body and medium acidity
Sauvignon Blanc
- not lowest price points
- Vigorous nature makes it high yields
- Herbaceous flavours can dominate if unripe
What chemical can be used at multiple points during the winemaking process to prevent oxidation and inhibit the growth of microorganisms?
Sulfur dioxide (SO2)
Explain the winemaking choices in inexpensive white wines
- Avoid oxidation by monitoring SO2
- Grapes are destemmed, crushed and pressed
- Acidification is the most common ajustement since high yield inexpensive wine grapes grow in warm climate
- Juice is highly clarified to ensure fruity flavours
- Use of centrifuge to save time and money
- Fermentation in stainless tell tanks vessels at cool temperature to keep primary fruit aromas
- Commercial yeast for fermentation
- Malolactic can be prevented with SO2 or take place (chardo)
- Racked of its lees as soon as fermentation has finished
- Store in inert vessel
- Some staves or oak chips can be added for toasty flavours (Chardo)
- Residual sugar is there because of warm climate, or can be added with Rectified Concentrated Grape Must (RCBM)
- Typically stabilised, fined and steril filtered. Very short shelf life.
- SO2 is topped up at bottling
Explain the general principals of Production of premium white wines
- wide ranging category
- do not follow precise formula
- ## adapt their techniques according to vintage conditions, vineyards plot and style of wine
What are the aromatic grape varieties
Sauvignon Blanc
Riesling
Muscat
Gewurztraminer
Torrontés
What is the general winemaking rule for premium wines from aromatic grape varieties?
Retain and enhance the primary fruit character and aromatic potential in the final wine
What is the preferred climate for Premium Sauvignon Blanc ?
cool climate
Early ripening grape
where the climate help retain acidity and refreshing caracteristics
What are the two most famous region for premium Sauvignon Blanc ?
Loire valley, France (sancerre and Pouilly-Fumé)
Marloborough New Zealand
Chile, south africa and margaret River in Australia
Describe premium Sauvignon blanc wine from Sancerre and Pouilly Fumé
- Show elegance and restraint
- aromas and flavours of green apple , asparagus, wet pebbles
Describe premium Sauvignon blanc wine from Marlborough
similarly ccool but long hours of intense sunlight give vibrant flavours
Aromas of gooseberry, elderflower, grapefruit, passion fruit, herbaceous note.
What is the preferred climate for Premium Riesling ?
Cool climate
- Tolerant of cold winters and buds late so avoid spring frosts
But can also ripen in warm climate but lose delicacy
What is the profile of Premium dry Riesling from cool climate
green fruit flavours
floral notes
