CSW Viticulture & Winemaking 3 — Questions and Answers
Question 1: What does 'terroir' encompass in a vineyard context?
- Only the soil type beneath the vines
- The complete natural environment including soil, climate, and topography (Correct answer)
- The winemaking techniques used in the cellar
- The grape variety planted in a given site
Correct answer: The complete natural environment including soil, climate, and topography
Terroir is a holistic concept encompassing all natural factors—soil, subsoil, climate, aspect, drainage, and topography—that give a wine its distinctive sense of place.
Question 2: Which rootstock characteristic is most important when selecting rootstock for a Phylloxera-affected region?
- High sugar production
- Resistance to Phylloxera louse infestation (Correct answer)
- Tolerance of cold winters
- Ability to ripen fruit early
Correct answer: Resistance to Phylloxera louse infestation
Rootstocks derived from American Vitis species (such as V. riparia and V. rupestris) are resistant to Phylloxera, allowing European Vitis vinifera vines to be grafted onto them safely.
Question 3: What is the primary reason winemakers use malolactic fermentation (MLF) in red wines?
- To increase alcohol levels
- To convert sharp malic acid to softer lactic acid (Correct answer)
- To add residual sugar
- To increase color stability
Correct answer: To convert sharp malic acid to softer lactic acid
MLF converts the harsher-tasting malic acid into softer lactic acid via lactic acid bacteria, reducing perceived acidity and adding complexity.
Question 4: In red winemaking, what is the purpose of 'pumping over' (remontage)?
- Transferring wine between tanks for blending
- Pumping fermenting juice over the grape skin cap to extract color and tannins (Correct answer)
- Removing sediment from the bottom of the tank
- Adding nutrients to the fermenting must
Correct answer: Pumping fermenting juice over the grape skin cap to extract color and tannins
Pumping over draws juice from the bottom of the fermentation vessel and sprays it over the floating cap of skins to extract color, tannins, and flavor compounds.
Question 5: What is 'cold stabilization' intended to remove from wine before bottling?
- Excess tannins
- Tartrate crystals (cream of tartar) (Correct answer)
- Residual yeast cells
- Volatile acidity
Correct answer: Tartrate crystals (cream of tartar)
Cold stabilization chills wine near its freezing point to precipitate potassium bitartrate (tartrate) crystals before bottling, preventing their formation in the bottle.
Question 6: Which grape training system is characterized by a single horizontal wire with canes or spurs extending in both directions?
- Gobelet (bush vine)
- Guyot (Correct answer)
- Geneva Double Curtain
- Vertical Shoot Positioning (VSP)
Correct answer: Guyot
The Guyot system uses one or two canes tied horizontally to a wire with shoots trained vertically upward, and is widely used in Bordeaux and Burgundy.
Question 7: What does 'Brix' measure in grape growing and winemaking?
- The pH level of grape juice
- The sugar content of grape juice as a percentage by weight (Correct answer)
- The total acidity of the must
- The alcohol level of finished wine
Correct answer: The sugar content of grape juice as a percentage by weight
Brix measures dissolved sugar content in grape juice; winemakers use it to estimate potential alcohol and determine optimal harvest timing.
CSW Viticulture & Winemaking 3
What does 'terroir' encompass in a vineyard context?