Chapter 5: Fermentation and Still Wine Production Flashcards
What happens to grapes soon after harvest?
Grapes will immediately begin to degrade and oxidize; Unbroken grapes will begin to raisin; Broken grapes will begin to ferment (in unpredictable ways). Think vinegar!
How do winemakers protect the harvested grapes before beginning wine making process?
Pick at night; Store in cool/covered containers; Sulfur could be used
What does adding Sulfur to wine/grapes do?
Sulfur combines with O2 to form sulfur dioxide. Sulfur Dioxide inhibits the growth of yeast and bacteria (avoiding early fermentation) and prevents browning from oxidation
What is considered Pre-Fermentation?
Anything that gets the juice ready to ferment including grape sorting, crushing, destemming etc.
What is the purpose of sorting?
Helps to remove debris, unripe or damaged fruit. Typically done by hand but can also be done my mechanical intervention; Rigorous sorting tends to yield higher quality wines
The process of breaking open the grapes and releasing their juice.
Crushing
What is “whole berry” or “whole cluster” pressing and benefits?
Is when the winemaker chooses to leave the stems and berries together when crushing. This maybe done to create whites with some tannin, body or desired flavours; lighter red wines can sometimes benefit from this process as well.
Skins are macerated with juice extracts for a short period of time; During time the juice and berries are chilled this is known as a…
“cold soak”
Known as the highest quality juice, high in sugar and lower in tannins
“free run” occurs after pressing
A form of a modern day press where balloons press on grapes to squeeze out juice
Bladder Press
What is Pomace? And what is it used for?
The leftover debris of seeds and skins after pressing has occurred. Can be used in farming practices as compost or to make pomace brandies like grappa or marc
Process of separating skins from grapes
Pressing
Describe why a winemaker may decide to Adjust the Must
For a variety reasons stemming from weather conditions too cool (not enough sugar) or too warm (not enough acidity). This process is subject to local regulations.
The process of adding only enough sugar to achieve proper alcohol levels is known as…
Chaptalization
Explain what acidification is and why it might be performed.
This is the process when a winemaker may add acid into the wine. This can be done by adding Tartaric Acid (most common naturally derived acid in grapes). This is done to ensure the right balance of acidity to sugar/alcohol levels
How can a winemaker lower the acid levels of wine?
Using potassium or calcium bicarbonate or by adding grape juice/water.
What is Debourbage?
Juice settling a period of time where the freshly pressed juice may sit for a short period of time to either allow sediment to settle or for more juice to be produced and added.
Stainless steel is often considered ___ because it does not impart flavour into the wine.
Inert
Often added to wine to prevent early fermentation
Sulfur
Can be done to speed up the process of fermentation
Inoculation introduction of must with a cultured (usually commercially produced)
Most common strain of yeast in winemaking
Saccharomyces cerevisiae
Typical temperature range for fermenting white wines
50 - 60 degrees F
Typical temperature range for fermenting red wines
85 - 95 degrees F but lower 60 - 70 degrees for lighter styles like Pinot Noir
What is cap management and what are common methods.
Cap management is necessary mostly in the production of red wines as it is the process of keeping the grape solids (skins) in contact with the must. Natural byproduct of the fermentation (CO2) pushing the skins to the top of the vessel. Common methods are Punch Down, Pump Over, Rack and Return, or a more modern form called Rotofermentation.
French term delestage is also known as…
Rack and Return where the juice is drained and then sprayed over the grape solids. More aeration than Pump Over.
Enzymatic Fermentation that does not require yeast or bacteria. And typical region that uses this process.
Carbonic Maceration; Fermentation is started in whole unbroken grapes in the absence of oxygen; Grapes begin to break-down the sugars and create alcohol. Not common to be 100% carbonic maceration. Beaujolais Nouveau.
Other terms for Rose
Rosado in Spanish, rostao in Italian and Weissherbst in German
Name three grapes that takes to the botrytis process?
Chennin Blanc, Riesling and Semillon
Grapes left on vines during cold and grapes are frozen before harvesting. Name styles of wine and common grapes.
Icewine or Eiswein. Typical grapes can be Riesling, Gewurztraminer, Chenin Blanc, Cab franc.
Name three methods used to make sweet wines and describe process
1) Refrigeration: helps to stop yeast activity to leave some sugar behind. Sterile filtering or sulfur is required to kill yeast to avoid fermentation after bottling. 2) Adding sweetness: by allowing wine to ferment dry, and then adding sugar, grape concentrate or unfermented juice (with proper measures). Fortification: Adding distilled spirits during fermentation can kill yeast and stop fermentation.
What is cryoextraction and how is it used?
It can be used to freeze the grapes post harvest to create sweet wines but can not be called icewine
Who is the NOP
National Organic Program which sets labeling standards in the US. Minimum of 95% organic to be labeled as organic; avoid anything winemaking that is on the prohibited list
Term for Organic Wine in Europe
Vin Biologique; contains 30-50% less sulfur than non-organic wines
Can sulfur be used in biodynamic wine practices?
Yes, but must be kept to a minimum.
Explain what kosher wine is outside of Israel?
Grapes can be grown anywhere but from winery to bottle under rabbi and Orthodox Jews care until shipt. Cannot use fining animal based products such as egg whites or gelatin.
Mevushal wine
Is free from the same restrictions of kosher wine; The wine is briefly exposed to high heat via flash pasteurization.
Where did Orange wine orginate?
Republic of Georgia over 5,000 years ago
Juice settling a period of time where the freshly pressed juice may sit for a short period of time to either allow sediment to settle or for more juice to be produced and added.
Juice Settling or Deborbage
Why is Acetobacter a concern during fermentation?
Acetobactor could form at the top of a tank when a wine is fermenting if the cap is allowed to sit to long above the juice. This could cause the formation of acetic acid (gives off a vinegar aroma)
Name two things a refractometer can be used for
1) to measure the sugar content of grape juice
2) to measure approx alcohol content of wine at final stages
What is Brix
Is a way to measure the potential alcohol content of a wine
Typically each gram of sugar translates to 1/2 gram of alcohol
High vines are more common in _______ with ______ moisture
Cooler; High
Low Vines_______ exposure to the sun and ___________ temperature variations. Most common in ______ climates
Reduces; Moderate; Hotter
In very dry regions, vines are spaced further apart, why?
It increases their ability to access nutrients in the soil.
What is the value of closely spaced vines?
To limit each vines vigor, limiting production and improving quality.
Different names for noble rot?
Pourriture noble (French) Edelfaule (German)
Why winemakers use sulfur
Prevents grape turning brown; spoilage from bacteria and yeats as well as prevents early fermentation.
A type of device that can we used to gently extract more liquid from grapes
Bladder presses
Extracted wines are ….
Typically deeply colored, highly tannic, bursting with flavors. Typically requires time in bottle to mature.
Delestage
French term for pump over
Why might a winemaker chose to ferment at a lower temp for a red wine
Thin skinned more delicate wines like Pinot typically ferment at a lower temp to keep fragrance but keep the wine lighter
Explain carbonic maceration and where it is common
Whole cluster grapes are places into a tank. CO2 is adding to remove all oxygen. Fermentation then begins within the berry by breaking down diagrams and converting to alcohol. Once this process has occurred usually goes through another round of standard fermentation. Common in Beaujolais but used by other winemakers to achieve a certain flavor profile and style.
Saignee
Process used sometimes for rose production. Red grapes are crushed left on juice for 2-29 hours. The grapes are pressed off and used to make a red wine while lighter juice is made into rose.
Pressing typically occurs _________ fermentation in ___________ wines and. ___________ fermentation in red wines. The timing can vary for the production of _______ wines.
Before; After and Rose
Late harvest grapes can be turned into sweet wine if grown in __________ to maintain _________ levels
Cool; acid
In sparkling wine production it is common for bottles to be stored on a _________ for _________ to take place
Pupitre (riddling rack) and remuage (riddling)
Autolysis
Process of yeasts dying, decomposing and becoming part of the sparkling wine imparting toasty nutty flavors.
