Common Elements in Winemaking and Maturation Flashcards
Why would a winemaker choose to control each part of the wine making process instead of adopting a more hands-off approach?
Because they have the scientific knowledge, the means and the will to achieve a desired style that might not happen by chance with minimal intervention.
From harvest to winemaking, why would a winemaker make every effort to protect its wine from oxygen?
To make a wine dominated by PRIMARY FRUIT characteristics.
What are some ways to prevent undesired oxidation from harvest to winemaking?
Anaerobic winemaking:
-Night harvest & transport in cool conditions
-Careful use of antioxidant such as sulfur dioxide (SO2)
-Filling airtight winery equipment with carbon dioxide (CO2) or Nitrogen (N)
-Use air-tight vats (steel or cement) avoid oak
Why would a winemaker allow controlled levels of oxygen to come in contact with the wine during MATURATION?
Oxygen in maturation can:
- Soften tannins in red wines
- Add complexity in flavors (primary fruit aromas give ways to TERTIARY characteristics: leather, earth…)
Red wines become paler and tawny/ brown
White wines become deeper and orange/ amber/ brown
In a blind tasting, what would be VISUAL clues that a wine was exposed to oxygen?
Oxidation occurs FASTER in oak vessels that are…
Smaller.
There is larger proportion of wood surface to wine in small barrels than large ones.
In a blind tasting of fortified wines, what would be aromatic clues of a deliberately oxidized style?
Pronounced tertiary aromas of Caramel, Toffee and Nuts
What are some deliberately oxidized styles of fortified wines?
-Olorosos Sherry
-Tawny Port
-Rutherglen Muscat
When oxidation is NOT intended (because of bottle closure failure for example) what can happen to the oxidized wine?
-unusual browning
-loss of fresh fruit (stale smell)
-bacteria might eventually turn the wine into vinegar
Why is SO2 so often used from harvest (to protect grapes) to bottling (to protect the finished wine) ?
Because SO2 acts as an ANTIOXIDANT and ANTICEPTIC
Why is SO2 monitored throughout the winemaking process and “topped up”?
Because once SO2 has bond with oxygen, it loses it antioxidant properties, and the wine is no longer protected against oxidation.
What are some problems associated with too high levels of SO2?
- Muted fruit aromas & harshness
- Toxicity (legal restrictions exist)
- May cause allergies for some consumers
What are some antiseptic effects of SO2?
SO2 is toxic to many strains of yeasts and bacteria that can produce off flavors and undesirable smells into wines.
Why would a winemaker mature a wine in NEW oak barrels?
Besides the small (desirable) levels of oxidation, oak will release tannin (structure) toast, vanilla, smoke and clove (from new oak)
What are 2 origins of oak to make barrels?
America
Europe
What are 3 European countries that produce oak?
France, Hungary, Russia…
What is the size of a Bordeaux Barrique?
225 L
What is the size of a Burgundy Pièce?
228 L
Larger oak casks can contain…
500 L , 600 L, 2,000 L, 10,000 L
Why would a winemaker consider the “level of toasting” when purchasing new oak barrels?
Because the level of heat and time applied to the staves in the process impacts the tannins and flavors of oak to give different flavors of sweet spices, toast, smoke…
Why do some winemakers prefer old oak barrels?
Because they want more subtle toasty flavors and less tannin from oak. This is better achieved with casks that are 4 years old or more.
Why would a winemaker use oak alternatives such as staves or chips to insert in stainless steel vessels together with an oxygenation device?
To obtain oak flavors and replicate the oxidizing effect of barrel aging without the high COSTS of barrels (typically not for premium wines)
What are “INERT” vessels?
Vessels that do NOT impart any flavors from oak or oxygen. (Steel & Concrete)
Why are some advantages of stainless steel tanks ?
Easy to clean, they don’t leak.
Can be made in any shape and size,
Can incorporate temperature control.
What are some advantages of concrete vessels?
Lined with epoxy resin, they don’t leak.
Somewhat easy to clean
Their thickness helps regulate temperature.
At reception of grapes in the winery, what tool, used for PREMIUM winemaking helps discard unripe and/or rotten grape?
A sorting table
What are 3 options available to a winemaker in the processing of GRAPES, depending on the desired wine?
Destemming, Crushing, Pressing
In cool climates, what are some ADJUSTMENTS authorized if a MUST (grape juice) lacks natural sugars for a minimum level of alcohol?
-ENRICHMENT through Chaptalization (addition of beet sugar in the must) or Rectified Concentrated Grape Must (RCGM) before or during fermentation.
-Removal of water in the must
In warm climates, what ADJUSTMENT is authorized if a MUST lacks natural acidity to balance other elements in the finished wine?
ACIDIFICATION by tartaric acid.
In cool climates, what ADJUSTMENT is authorized if a MUST is too acidic (because of slightly unripe grape) ?
DEACIDIFICATION: Addition of an alkali to neutralize excess of acidity.
What is the species of yeast responsible for the conversion of sugar into alcohol in winemaking?
SACCHAROMYCES CEREVISIAE
Give reasons why Yeast will STOP fermentation?
-The temperature is below 5°C or above 35°C and
the alcohol level is already too high
-There is TOO MUCH sugar or NO MORE sugar
-The must lacks sufficient other YEAST NUTRIENTS
-SO2 or ALCOHOL is added in sufficient quantities
-Yeast are removed via filtration
Why would a wine maker pay attention to temperature (T°) control in winemaking?
-Because yeast can die at high T°
-Low T° avoid loss of volatile (floral) aromas and encourage fruity character in white wines
-Higher T° help with color and tannin extraction
-T° has a huge impact on quality and consistency.
What is MLF or MLC?
Malolactic Fermentation or
Malolactic Conversion
What causes MLF/ MLC
A Lactic Acid Bacteria either present naturally or inoculated into the wine
Why would a winemaker encourage/ provoke MLF/ MLC in a wine?
-To soften high acidity (Almost always done in red wines, sometimes in white wines)
-It create buttery flavors in a white (thus adding complexity) wine (and CO2)
Why would a winemaker block MLF/ MLC in a white wine? (and how to do it)
-Because the acidity tend to be on the low already
-Because the aim is to produce a pure expression of an aromatic grape variety.
(Low T° and SO2 or filtering bacteria will block MLF)
What are lees?
Dead yeast cells and grape fragments left in suspension after fermentation.
Heavy particles (gross lees) fall to the bottom of the tank in hours while lighter particles (fine lees) are removed gradually during maturation.
GROSS LEES are removed because they can cause unpleasant aromas in the finished wines, but why a winemaker would choose to keep the wine in contact with FINE LEES
-To add extra flavors and complexity
-To add richer texture to the wine
What type of maturation is most suitable if a winemaker aims to retain PRIMARY FRUITY aromas?
SHORT (only a few months)
In INERT vessels
What type of wines benefit from only a SHORT maturation period in inert vessels?
Premium aromatic wines designed to show purity and pronounced grape aromas.
Inexpensive rosé, white and red wines
Wines that deserve a LONGER period of maturation before bottling are wines that have…
- Intense aromas that can develop in a positive way by interaction with oak barrels and show complexity with primary, secondary and tertiary aromas
- sufficient levels of tannins, acidity and/ or alcohol.
Blending is key in almost EVERY wines (even single varietal wines) Give 3 reasons why a winemaker may use blending:
- For better balance between different components
- For Consistency between batches or vintages
- Achieving a specific style from simple to complex for ageing or not
What can actually be blended?
Wines from different…
vineyard plots, varieties, levels of ripeness, batches vinified or matured differently (free run vs press; MLF encouraged vs MLF blocked, oaked vs unoaked) or vintages
Why would a winemaker chose to clarify their wines?
Because most customers expect their wines to be perfectly clear
What are 3 clarification techniques?
Sedimentation, Fining & Filtration
Why would a winemaker chose to MINIMIZE clarification in a wine?
-Because they believe that harsh clarification can strip a wine from some of its desirable flavors and texture.
-Because their customers value the concept of minimal intervention and are not concerned by sediments.
What is racking?
The process of removing gross lees in a vessel after sedimentation by gravity.
Why would a winemaker use a “fining” agent?
To further clarify his wine. A fining agent help clump up fine particles later removed by filtration.
At what steps can a winemaker use filtration?
-After fermentation and during maturation to remove gross and fine lees quickly.
-before bottling to ensure the wine is clear.
What are 2 filtration methods?
- Depth Filtration (for very cloudy wines)
- Surface Filtration (for wines gone through depth filtration) to sterilize/ remove yeast & bacteria (before bottling)
Against which 3 elements would a winemaker stabilize a wine?
Tartrate
Microbes
Oxygen
How to prevent tartrate crystal formation in a bottle?
Chill the wine to 0° before bottling, this causes the crystal to form, which can be removed by filtration.
Microbiological spoilage is most likely to occur in which types of wines?
Wines that did not go through MLF
Wines that are low in acidity and alcohol and have some residual sugar
What wines are more likely to be resistant to microbiological spoilage?
-Fortified wines because of their high levels of alcohol, which is toxic to microorganisms
-High acid wines that underwent MLF are also resistant to microbiological spoilage.
What are some ways to protect a wines from microbiological spoilage?
Strict hygiene in the winery
Careful use of SO2
Sterile filtration before packing/bottling
What are some techniques to minimize oxidation at bottling?
Flush bottles with CO2 or N before filling
Use proper closure
What are 2 common alternative options to glass bottle?
-Plastic bottles (Lighter than bottle, but not suitable for long time storage as they are not fully air-tight)
-Bag in Box (for large volume to be consumed within 18 months)
What are 3 closures for wine bottles?
-Cork (traditional, allowing tiny amount of O2)
-Synthetic closure (for short time storage)
-Screw Caps (best to preserve primary aromas)
Most wines are meant to be consumed within a year after market release. What are 3 exceptions (which benefit from bottle ageing in proper conditions)?
Vintage Ports
The finest German Rieslings
Grand Cru Classés of Bordeaux
