Winemaking Flashcards
What are the steps in winemaking?
- De-stemming (winemaker choice)
- Crushing/pressing (soft or hard)
* Must adjustments (if any) - Alcoholic Fermentation
- Malolactic Fermentation
- Devatting/Racking
- Filtration
- Blending (if doing)
- Stabilization
- Aging
- Bottling
What is de-stemming?
Removal of berries from the stems
- Done totally or partially in 85-90% of wines
- May be left on for wines that are light on tannins
- Stems impart woody character
Facts about crushing/pressing
- Can be hard or soft
- Hard pressing extracts harsh tannins from the seed into the wine
- Soft press is preferred
What are adjustments that can/are made to the must?
- Acids
- Sugars (Chaptalization)
- Sulfur Dioxide
- Yeasts
What happens in alcoholic fermentation?
Yeast converts sugar to alcohol and carbon dioxide, and creates heat in the process.
What is the difference between low temperature fermentation and high temperature fermentation?
Low temperature fermentation imparts a fresh profile to wine.
High temperature fermentation imparts a stewed, heavier profile to wine.
How is alcoholic fermentation controlled?
Through controlling the temperature on the fermentation tank.
Name and describe the two types of yeasts?
Native yeast: present on grape skins and in the air of the winery. These usually result in rustic, traditional wines.
Selected yeast: winemaker purchases. Results in a predictable outcome and obtains specific desired flavors.
What are the elements of wine?
Water - 80%
Alcohol - 7%
Trace Substances - 13%
What is pomace?
Solid portion of crushed grapes.
What is devatting/racking?
Separating wine from lees by draining wine from the top of tank or barrel and leaving solids at the bottom.
What is malolactic fermentation (explain the process)?
It is the second fermentation of wine that occurs naturally when wine is placed in the barrel after the first fermentation (alcoholic fermentation). Lactic bacteria eats the malic acid present in the wine.
- all red wines undergo this process
- few white wines undergo with Chardonnay being the most common exception
How does malolactic fermentation affect wine?
Softens and thickens wine, imparting creamy or buttery aromas.
What is carbonic maceration?
*Takes place in a sealed tank pumped with carbon dioxide resulting in an oxygen free environment.
Grape berries are left whole (uncrushed/unpressed) and fermentation takes place inside each berry using native yeast. Also known as whole fruit fermentation.
*Grape berries are bathed in carbon dioxide
*Results in aromatic, fruity wine with bright color (ex.Beaujolais)
What is maceration?
Soaking of grape skins with juice to extract aromas, tannin, and color from skins. Increases aroma, weight, and texture of wine.
What is must?
Juice and skins mixture that comes from grapes.
What are the acids present in wine?
- Tartaric
- Malic
- Citric
- Acetic
- Succinic
What is a fixed acid?
Acids present in grapes, that do not evaporate.
What is a volatile acid?
Acids that come from the fermentation process. They can evaporate.
Name the fixed acids in wine and describe the characteristic imparted by each.
- Tartaric - imparts freshness
- Malic - imparts aggressiveness
- Citric - imparts sourness
Name the volatile acids in wine and describe the characteristic imparted by each.
- Acetic - imparts an aroma of nail polish
* Succinic - imparts a vinous aroma
What are the components of wine?
- Water - Primary Component
- Polyphenols - Anthrocyanins (color)
- Acids (Fixed) - Come from grape
- Acids (Volatile) - From fermentation (created by yeasts)
- Alcohol - Mostly ethyl; some methyl
What are the methods of aging wine?
- Wood
- Steel
- Bottle
What are the factors that influence aging potential?
- Ethanol
- Temperature
- Container Features
- Tannins
- Total Acidity and Ph
- Vibrations
How does ethanol affect the aging potential of wine?
The higher the amount of ethanol (alcohol), the better the aging potential of the wine.
How does temperature affect the aging potential of wine?
Proper storage temperature will preserve the wine and allow aging.
How do tannins impact the aging potential of wine?
The higher the tannins, the longer a wine can age.
How do container features impact the aging potential of wine?
Natural corks allow aging and prevent oxygenation of wine, than cheap synthetic corks.
Screw caps do not allow any oxygen exchange lessening the possibility of aging
Name the types of wine bottle seals.
- Cork
- Screw Cap
- Synthetic Cork
What are the pros and cons of cork bottle closures?
Pros:
- age development
- airtight seal
- environmentally friendly
- tradition
Cons:
*Cork taint (TCA)
What are the pros and cons of screw cap bottle closures?
Pros:
- cheaper
- convenient
- no TCA
Cons:
- sulfidization
- non-biodegradable
- no aging development
- plasticides
What are the pros and cons of synthetic cork bottle closures?
Pros:
- cheapest
- no TCA
Cons:
- not airtight
- plasticides
- non-aging
- non-biodegradable
What are the three types of wine aromas, and how are they derived?
- Primary aromas - typical of a grape varietal
- Secondary Aromas - typical of fermentation
- Aging aromas - come out with aging
*all three are required for a wine to be considered complex
What are the ways to produce sweet wine?
- Interrupt fermentation
(lower temperature, add sulfites, or add alcohol) - Add sweet component
(concentrated grape musts) - Concentrate sugars naturally
(dry grapes, freeze grapes, botrytis
What are the methods to create rose wine?
- Saignee
2. Rose De Press
Describe the Saignee process for rose wine, and what style of wine results.
Grapes skins remain in the juice for 4- 12 hours.
Creates a bolder, darker, more structured rose with some tannin.
Describe the Rose de Press process for rose wine, and what style of wine results.
No maceration of skins with juice
Direct cold press, lasting up to 4 hours.
Creates a lighter paler, more aromatic/perfumed rose wine.
What are the categories of Organic Wine?
- 100% Organic Wine
- Organic Wine
- Wine Made with Organic Grapes
Define 100% Organic Wine.
Contains 100% organic ingredients and processing aids.
Define Organic Wine.
- 100% organic grapes
- At least 95% organically derived ingredients
- No added sulfites
Define “Wine Made with Organic Grapes”.
- 100% organic grapes
- At least 70% organically produced ingredients n finished product
- Added sulfites allowed.
Where are tannins derived from?
- grape skin
- grape stems
- wine barrel
Why/when would a winemaker adjust the acids (acidification) in a wine?
If the vintage is low on acid or hung on the vine too long.
- this is illegal in Europe for classified wines
- used widely in the new world
- done more in warmer climates
Why/when would a winemaker make adjustments to the sugars (chaptalization) in a wine?
If the grape did not ripen enough. Adding sugar gives the yeasts something to eat and increases alcohol level in the wine.
*illegal in Europe for classified wine.
Why/when would a wine maker make adjustments to the sulfur dioxide (sulfites) in a wine?
Always! Sulfur dioxide is essential in wine; it is added as a preservative and to combat wild or unwanted yeasts.
Why would a winemaker choose to use native or indigenous yeasts?
To impart native or terroir characteristics to a wine.
Why would a winemaker choose to use selected yeasts?
To have a predictable outcome and obtain specific flavors in the wine.
*yeast species should be saccromyces cerevisae
What are the important considerations for a winemaker when choosing a barrel for aging?
- Wood type - American, French, Slavonian etc.
- Charring level
- Barrel size - determines how much wood is in contact with the wine
- Neutrality - new or used barrel
- slavonian oak is more neutral
- american oak is more invasive
- French oak is elegant, giving vanilla, sweet, subtle flavors
What are the effects of oxygen on wine?
A little is good: softens the wine, increases complexity
A lot is bad: results in spoilage, aromatic stripping, and browning
What happens as wine ages?
- More flavors and aromas develop (becomes more complex)
- Wine softens and becomes more balanced
- tannins go from firm to silky
- acidity decreases, sapidity increases - Color evolves (darkens)
- Color and acid precipitation