Common elements in Winemaking and Maturation - WSET L3 in Wines Flashcards
What are the three main components of grape pulp?
Water, sugar, and acids (primarily tartaric and malic acid).
What is the role of tannins in winemaking?
Tannins add structure, astringency, and aging potential, especially in red wines.
What is the purpose of sulfur dioxide (SO₂) in winemaking?
Acts as an antioxidant and antiseptic to protect wine and prevent spoilage.
What are the two main fermentation processes in winemaking?
Alcoholic fermentation and malolactic fermentation.
What is the typical alcohol range in still dry wines?
8% to 15%.
How does oxygen affect wine during maturation?
Softens tannins, develops tertiary aromas, and changes wine color.
What is protective winemaking?
A method that minimizes oxygen exposure to preserve primary fruit flavors.
What are the benefits of aerobic maturation in oak barrels?
Adds complexity, softens tannins, and develops tertiary flavors like leather and nuts.
What is the effect of barrel size on wine?
Smaller barrels (e.g., 225-liter barriques) provide greater oak flavor.
What is the purpose of toasting oak barrels?
Enhances flavors like toast, vanilla, and spice in wine.
What are oak alternatives in winemaking?
Oak chips or staves added to wine during fermentation or maturation.
What is chaptalization?
Adding sugar to grape must to increase alcohol in the final wine.
How can winemakers adjust acidity?
By adding tartaric acid (acidification) or neutralizing excess acid with alkali (deacidification).
What temperature range is needed for fermentation to occur?
Between 5°C and 35°C.
What is malolactic fermentation (MLF)?
Converts tart malic acid to softer lactic acid, reducing acidity and adding buttery flavors.
How can fermentation be stopped to retain sugar in wine?
By chilling, adding SO₂, or fortifying with grape spirit.
What is the purpose of fining?
To remove haze or unstable particles from wine before bottling.
What are the main methods of wine clarification?
Sedimentation, fining, and filtration.
What is racking in winemaking?
Transferring wine from one vessel to another to leave sediment behind.
What is depth filtration?
A filtration method using thick material to trap solid particles in cloudy wine.
What is surface filtration?
Uses fine sieves to trap particles and can achieve sterile filtration for bacteria and yeast.
What are tartrate crystals?
Harmless deposits formed by tartaric acid that can be removed by cold stabilization.
Why is microbiological stability important in wine?
Prevents spoilage by yeast or bacteria, especially in low-acid, low-alcohol wines.
How does wine oxidize?
Oxygen exposure causes loss of fresh fruit flavors and turns wine brown.
What are the benefits of inert winery vessels?
They don’t add flavor or allow oxidation, ideal for preserving fresh fruit characteristics.
What are examples of inert winery vessels?
Stainless steel and concrete tanks.
Why are screw caps becoming popular?
They prevent cork taint, preserve fruit flavors, and provide an airtight seal.
What is cork taint caused by?
Trichloroanisole (TCA), giving a musty, cardboard-like aroma.
How do plastic bottles affect wine storage?
Allow small amounts of air to enter, reducing freshness over time.
What is the primary purpose of glass bottles?
To provide a strong, airtight container for long-term wine storage.
How does blending improve wine?
Adjusts balance, enhances consistency, and achieves a desired style.
What are lees in winemaking?
Dead yeast and grape fragments that settle after fermentation.
What is the effect of lees aging?
Adds texture, complexity, and flavors like bread and biscuit to wine.
What is sterile filtration?
Removes yeast and bacteria to prevent spoilage before bottling.
Why is temperature control important during fermentation?
Prevents overheating and allows control of aroma and flavor development.
How is pre-bottling maturation managed?
Wines are stored in tanks or barrels to develop flavors and structure.
What is the function of blending during maturation?
To combine different components, such as press fractions or grape varieties.
How do winemakers stabilize wine?
Through processes like cold stabilization, sterile filtration, and proper SO₂ management.
What is the purpose of oak in winemaking?
Adds flavors, tannins, and allows controlled oxidation.
What is a barrique?
A 225-liter oak barrel used in winemaking.
What are inert bottling vessels used for?
Storing wine with minimal oxygen exposure, preserving freshness.
What is the main use of concrete tanks in winemaking?
Fermentation and maturation with natural temperature regulation.
Why is grape selection important during processing?
Ensures only ripe, healthy grapes are used for high-quality wine.
What is the purpose of pressing in winemaking?
Separates juice from solid grape material.
What are pneumatic presses?
Modern presses using inflatable tubes for gentle juice extraction.
What are gross lees?
Heavy sediment that forms after fermentation.
What is sedimentation in winemaking?
Allowing solids to settle naturally at the bottom of the vessel.
Why is carbon dioxide used during protective winemaking?
To displace oxygen and prevent oxidation.
What happens to red wine during aerobic maturation?
Tannins soften, primary fruit fades, and tertiary aromas develop.
What is the difference between free-run juice and press wine?
Free-run juice is the liquid released without pressing, while press wine comes from pressing the grape solids.
How does fermentation temperature affect wine style?
Lower temperatures preserve floral and fruity aromas; higher temperatures extract more tannins and color.
What is spontaneous fermentation?
Fermentation using ambient yeast naturally present on the grapes and in the winery.
Why might a winemaker use cultured yeast?
For consistent fermentation and predictable flavor outcomes.
What is Rectified Concentrated Grape Must (RCGM)?
A colorless, odorless syrup used to enrich grape must by adding sugar.
What are the risks of high sugar levels during fermentation?
Yeast may struggle to ferment or stop working due to high alcohol levels.
What is partial fermentation used for?
To create wines with residual sugar, like certain off-dry or sweet styles.
How is SO₂ monitored during winemaking?
Regular testing ensures levels are sufficient for protection without affecting flavor.
What are lactic acid bacteria?
Microorganisms responsible for malolactic fermentation.
What types of oak are commonly used in winemaking?
European oak (e.g., French, Hungarian) and American oak.
How does oak origin affect wine flavor?
European oak imparts subtle spice and tannins; American oak adds coconut and vanilla notes.
What is the role of epoxy resin in concrete tanks?
Makes the tanks waterproof and inert.
Why might a winemaker choose a stainless steel tank?
For ease of cleaning, temperature control, and preserving primary fruit flavors.
What are the benefits of blending wines from different vineyards?
Increases complexity, balances flavors, and maintains consistency.
What is press fraction separation?
Separating juice released at different stages of pressing for tailored blending.
What are the benefits of pre-bottling clarification?
Ensures clarity, removes unwanted particles, and improves stability.
Why might some winemakers avoid filtration?
To retain texture and preserve delicate flavors.
What is a potential downside of bag-in-box packaging?
Air can slowly permeate the bag, reducing wine freshness over time.
How does screw cap oxygen transfer affect wine aging?
reserves fresh fruit flavors but may limit development of tertiary aromas.
What is the role of malic acid in wine?
Adds tartness but can be softened by malolactic fermentation.
How can a winemaker stop fermentation using temperature?
Chilling the wine below 5°C halts yeast activity.
Why is cold stabilization used in winemaking?
To force tartrate crystals to form and remove them before bottling.
What causes a wine to throw sediment over time?
Tannins, pigments, and other compounds clump together and settle.
What is a key difference between noble rot and grey rot?
Noble rot is beneficial for sweet wines, while grey rot causes spoilage.
What is the effect of sulfur dioxide on unwanted bacteria?
It inhibits their growth, preventing spoilage.
Why might a winemaker ferment in small batches?
To maintain control and create more blending options.
What is the purpose of whole-bunch fermentation?
Adds freshness and complexity, often used in Beaujolais or Pinot Noir.
What is enrichment, and why is it used?
Adding sugar to increase alcohol in cool climate wines with low sugar levels.
What is the advantage of large oak vats?
They impart less oak flavor and allow slower oxidation compared to small barrels.
How does fermentation time affect wine style?
Longer fermentation extracts more complexity and tannins in reds.
What is the difference between white and red wine pressing?
White wines are pressed before fermentation, red wines after.
