Chapter 16 - White Winemaking Flashcards
What are the main purposes of skin contact?
- Enhance texture (by extracting small amt of tannin)
2. Enhance extraction of aroma compounds and aroma precursors
What happens when skin contact is used too much?
Wine can taste bitter and feel coarse
Why do some producers not want any skin contact? (Multiple reasons)
- Want to preserve fresh fruit aroma
- Minimal color extraction
- Smooth mouthfeel (no tannins)
- Want wines that can be drunk early (tannins need time to integrate with the wine and soften)
- If fruit is underripe, want to avoid extracting bitter flavors and astringent tannins
- Want to sell the wine early & cheaply - skin contact slows down the process and adds additional labor & equipment
Is skin contact more effective on aromatic or nonaromatic grapes? Why?
Aromatic because they have more aroma compounds to extract. These aromatic varietals also seldom see oak so this adds texzture
What are the 2 key factors that influence level of skin contact extraction?
Time and Temp
What makes a wine an orange wine? What are the classic characteristics?
Fermentation on skins
Notable levels of tannins. Flavors of dried fruit, dried herbs, hay, nuts
What are the pros of pressing whole bunches?
- Reduces chance of oxidation before and during pressing. Esp if inert gasses are used
- More gentle - stems help break up the mass of grape skins
- Provides juice that is low in solids, tannins, and colors
Why is whole bunch pressing usually only reserved for premium/small batch wines?
- Whole grapes take up more storage space
- Fewer grapes are pressed at once - takes more time
- Grapes must have been hand harvested
Free run juice vs Press juice - in terms of sugar, pH, tannins, color, solids
- More sugar
- Lower pH/higher acidity
- Less tannins
- Less color
- Less solids
What are press fractions and what are they used for?
Separated press juice
Different press fractions can be blended with the free run juice in the winemaking or maturation process to increase body and texture
What is hyperoxidation?
What happens during it?
What is the goal?
Technique of deliberately exposing the must to large quantities of oxygen before fermentation
Targets the compounds in the must that oxidize most readily. As they oxidize, these compounds turn the must brown. During fermentation, the compounds precipiate out, returning the wine to its normal color
Goal: stabilize the wine against oxidation after fermentation and remove bitter compounds (ie from unripe grape skins, seeds, skins)
Is Hyperoxidation more suitable for aromatic or non aromatic varietals?
Nonaromatic because it destroys most volatile aroma compounds (ie thiols, methoxypyrazines)
When does must clarification happen?
Between pressing and fermentation
After fermentation
What is the general percentage of solids in the must?
0.5-2%
How do you get solids in the must to be lower than 1% in white wine must?
Using pectolytic enzymes or centrifugation