L3- Sparkling Wine Production - Chap 41 Flashcards
What are the basic requirements for growing grapes for sparkling wine?
For sparkling wine:
-(1) Grapes should be relatively low in sugar compared to those used in still wines. This is because secondary fermentation (which gives wine bubbles) results in raising alcohol further by 1.2%-1.3%. The more sugar, the higher the alcohol. So for base wines-winemakers aim to produce base still wines with 10-11% alc.
-(2) Acid levels must be high so that sparkling wine can be made in a refreshing style. Despite low sugar concentration & high acid level, grapes must be sufficiently ripe so that they dont impart green herbaceous flavors.
Which regions are best for meeting the requirements of sparkling wines?
The coolest wine growing regions are the best as changes to sugar and acid happen slowly there, as do changes to the grape’s flavor.
In warm regions that produce sparkling wine, sugar levels rise and acid levels can fall quickly so winemakers in these regions will pick grapes early . This can, however, result in picking grapes that are still overtly green and herbaceous. As a result, cool regions are the best.
How are grapes for sparkling wine production typically harvested?
For premium sparkling wines grapes are typically hand-picked in order to retain whole bunches of unsplit grapes.
For inexpensive mass-produced wines, machine harvesting is common and the most efficient way of harvesting grapes before they accumulate too much sugar and lose their acidity.
When should pressing for sparkling wines occur?
Pressing should occur as soon as the grapes arrive at the winery.
Pressing should be gentle to minimize the extraction of colors and tannin. This is especially true when using black grapes for white sparkling wine.
The use of whole bunches helps with the gentle pressing and minimizing of extraction of color.
(Crushing is avoided to minimize contact between the skins and juice).
EU legislation determines the maximum amount of pressure that can be applied during pressing and the amount of juice that can be extracted from grapes.
What is the traditional method for making wines?
TRADITIONAL METHOD
This is when a still wine has undergone a secondary fermentation in the bottle that is is later sold in. It is most often used for premium sparking wine and is costly and time consuming.
What are the steps for making sparkling wine in the traditional method?
TRADITIONAL METHOD
Steps for making sparkling wine in the Traditional method:
(1) Grapes must be hand-harvested in whole bunches to ensure no split grapes
(2) Grapes are pressed in whole bunches to minimize the extraction of color by limiting the amount of time juice sits on the skins.
(3) Make the base still wine for the 1st fermentation
(4) Blend wines to achieve certain styles, improve balance and/or enhance complexity of the wine
(5) Secondary fermentation
(6) Yeast autolysis
(7) Riddling
(8) Disgorgement and corking
(9) bottle disgorgement
(10) bottle aging
How is base wine for sparkling wine made?
MAKING THE BASE WINE
After grapes are harvested and pressed, the grapes must undergo the first fermentation for the still base wine.
Usually this step takes place in temperature controlled stainless steel vats, but some winemakers use oak vats or barrels for some or all of their wines. The resulting base wine is completely dry with neutral flavors & high acidity. AT THIS STAGE - winemakers must decide whether the still wine will undergo malolactic conversion and/or a period of oak maturation before the second alcoholic fermentation.
Why is blending an important part of the sparkling wine making process?
BLENDING
Blending is an important part of the sparkling wine making process because it
1) allows the winemaker to achieve certain styles
This is important because some winemakers hope to make the “house style” year after year –particulary for non-vintage wines. Blending from different vineyard sites, varietals and/or vintages can help achieve consistency each year
2) Improve balance of the wine and/or
ex: Chardonnay is known to bring citrus fruit, finesse and longevity, where Pinot Noir brings more body
3) Enhances complexity of the wine
Blending old reserve wines can bring flavors of dried fruit to fresh young wines, Wines matured in oak can bring spice and broader texture. As a result grapes are fermented in different parcels to give many blending options
What happens during the secondary fermentation?
SECONDARY FERMENTATION
Once the blend is made up, a small proportion of liquer de tirage is added.
Liquer de tirage is a mixture of wine, sugar, yeast, yeast with nutrients and a clarifying agent.
The bottle is closed with a crown cap that includes a plastic cup insert.
Bottles are stacked horizontally in the producer’s cellars are cool at a constant temperature.
A slow fermentation takes place, the alcohol is raised by 1.2-1.3% and CO2 generated by the yeast dissolves into wine creating the sparkle.
The creates pressure in the bottle equivalent to 5 to 6 atmospheres.
What happens during the yeast autolysis stage for sparkling wine?
YEAST AUTOLYSIS
After the second fermentation the yeast in the bottle die and form a sediment of lees (dead yeast cells) in the bottle.
The process of yeast autolysis is when the lees release chemical compounds in the wine. This process impart flavors of bread, biscuit, and toasty notes to the wine.
Autolysis is usually most active the first 4-5 years . The more time wine spends on the lees the more of yeasty character it will have
(Lees contact can maintain the freshness of wine for years but normally does not happen)
What is the process of riddling?
RIDDLING
Riddling is one of two processes used to remove lees (the other is disgorgement).
Riddling involves moving a bottle from horizontal to an inverted vertical position.
As this happens, yeast sediment is dislodged and gradually slides down the bottle collecting in a plastic crown cap.
This was traditionally done by hand in an A-frame (“pupitre”) rack. very labor intensive and took up to 8 weeks to complete
Now a gyropalette mechanizes this process so that –cage holding 500 bottles which does the job in a matter of days
What is the process of disgorgement and corking?
DISGORGEMENT AND CORKING
Once riddling is complete, the neck of the bottle is placed in a very cold solution which freezes the neck of the bottle and holds the sediment in place (keeping wine clear)
The crown cap seal is removed and the pressure created by the dissolved CO2 ejects the frozen wine taking the sediment and plastic insert with it.
Wine is then topped off with “liquer d’ expedition” and sealed with a cork that is held secure by a wire cage
This whole process is now generally mechanized and the time it take to open and reseal the bottle is a matter of seconds
What is “liquer d’ expedition”?
What is dosage and what is it used for?
“Liquer d’ expedition” is a mix of wine and sugar. The amount of sugar determines the level of sweetness in the wine.
The level of sweetness is known as dosage. Dosage is used to balance the acidity of the wine and helps with some flavor development.
Some wines are made without sugar are are typically known as Brut Nature or Zero Dosage. A small proportion of wine will still be added to top up the bottle
How does bottle aging work with Sparkling wine?
Some premium sparkling wines may benefit from additional aging in the bottle but as a general rule, most sparkling wine is ready to drink when released.
Because most sparkilng wines are non-vintage dated it can difficult to know the actual age of wine in the bottle. As a result, many winemakers include disgorgement dates on the labels to provide greater clarity on freshness of wine.
What is the “Transfer Method” of making sparkling wine?
TRANSFER METHOD
The Transfer Method is an adaptation of the Traditional Method.
The processes of the transfer method are the same as traditional, up until the point of riddling.
At that time alll of the wine bottles are disgorged into a sealed tank under pressure.
The tank is filtered to remove lees, liquer d’expedition is added, wine is rebottled into a fresh bottle.
This gives good quality sparkling wine at a cheaper price and ensures consistency in batches.
Transfer methods will often be stated on labels, but traditional method still considered more prestigious.
