D4.C1. Standard Options in Sparkling Winemaking Flashcards
Why are the cool climates where grapes struggle to ripen are ideal for sparkling wines?
- The grapes are just-ripe in flavour, but retain the acidity
- Base wines have low alcohol (around 9–11% abv), which is important because the second fermentation used in many methods of making sparkling wines produces an additional 1–2% abv
What kind of regions are ideal to grow grapes for sparkling wine
- Regions that are at greater latitudes, such as Champagne, England or Tasmania
- Regions with local cooling influences, such as those near to the coast (Sonoma) or at high altitude (Trentodoc)
The grapes which are grown in warmer areas and have riper fruit flavours and lower acidity can be used to produce which styles of sparkling wines?
For short-aged wines (e.g. those made by tank method or with short time on the lees in transfer or traditional method)
What are the most commonly used grape varieties for making premium and super-premium sparkling wines?
Chardonnay and Pinot Noir
Why is Chardonnay well suited to the production of autolytic styles of sparkling wines
- Its subtle apple and citrus aromas and flavours compliment rather than compete with the biscuit or pastry aromas from yeast autolysis
- Early ripening of flavours is an asset in cool conditions and it also retains the high levels of acidity and low levels of alcohol needed in sparkling wines while avoiding under-ripe flavours
What does Chardonnay bring to the blend in sparkling wines?
- Apple and citrus flavours
- High acidity
Chardonnay is prone to which viticultural hazards and diseases?
- Spring frosts (early budding)
- Coulure and millerandage
- Powdery mildew
- Grapevine yellows
- Botrytis bunch rot
What does Pinot Noir bring to the blend in sparkling wines?
Body
Pinot Noir is prone to which viticultural hazards and diseases?
- Spring frosts (early budding)
- Coulure
- Downy mildew (mostly)
- Powdery mildew
- Botrytis bunch rot
- Fan leaf
- Leaf roll
What are the factors within the grape variety that can influence the style of the wine?
- Intensity of aromas (aromatic or neutral grape variety)
- Ability to retain acidity while ripening
- How the base wine responds to autolysis where applicable, for example, Chardonnay becomes creamy, whereas Xarel-lo becomes toasty and smoky
Why are the grapes for sparkling wines often grown at higher yields than for still wines?
- High acid levels, low potential alcohol levels and delicate flavours are desirable in most sparkling wines, and these characteristics are better achieved by high yields
- In cool, relatively rainy climates, such as Champagne, this can provide some assurance that even if some damaged fruit has to be removed, a reasonable sized crop can still be harvested
What is the priority of training and trellising techniques used to produce grapes for sparkling wines?
To obtain clean, healthy fruit
How can diseased fruits affect the taste of sparkling wines?
- The perception of any off flavours from diseased fruit can be enhanced by the effects of effervescence in the wine
- Laccase, released by botrytis-infected grapes can cause serious oxidation
What are the advantages of picking the grapes early for producing sparkling wine?
- To achieve the high acid, low alcohol profile
- Early picking also means that the grapes are less likely still to be on the vine as rainy autumn weather starts, reducing risk of fungal disease
Which factors determine the type of harvest for the sparkling wines?
- Location
- Wine laws
What are the advantages of hand-harvesting for sparkling wines?
- Sorting at picking
- Post-harvest selection to exclude disease-infected grapes
- Hand picking and collecting in small crates minimise the splitting and crushing of the grapes and oxidation of this juice along with extraction of phenolics
What are the disadvantages of hand-harvesting for sparkling wines?
- Slow
- Labor intensive
- Expensive
What are the advantages of machine-harvesting for sparkling wines?
- Faster
- Cheaper
- Diseases or damaged grapes can be removed by hand just prior to machine harvest (increases the cost)
- Permits night-time harvesting (oxidation is slowed down)
What is the disadvantage of machine-harvesting for sparkling wines?
It can rupture the skin of the grapes, resulting in phenolic extraction and oxidation
Why is whole-bunch pressing is often practised for premium traditional method sparkling wines?
- It is one of the gentlest forms of pressing providing a delicate juice that is low in solids and phenolics (including tannins and the anthocyanins)
- The stems also help to create a network of channels through which the juice can flow easily, minimising the pressure required
What is the disadvantage of using whole bunches for the production of sparkling wines?
Fewer bunches can be loaded into the press at any one time compared to crushed grapes, and therefore this process is more time consuming
Why should the pressing should be performed as quickly and gently as possible, especially for the black
skinned grape varieties for the production of sparkling wines?
It minimizes the maceration with and extraction from the skins, which would bring unwanted colour and tannins
Which types of presses are used for the production of sparkling wines? Why?
Both pneumatic and basket presses are commonly used, due to their ability to press very gently
Why is it common to split the juice into different press fractions?
- The different press fractions can make useful blending options
- Wines made from press juice tend to be faster maturing, and therefore this fraction can be useful in wines with a short maturation that are made for immediate consumption
What is the next step after the pressing, before the fermentation process begins for sparkling wines?
- The juice is clarified
- Winemaker can choose any of the options available for clarification when making still white wines
What can be done, if the press juice has excessive tannin or color?
Fining (e.g. with casein, gelatine or PVPP [polyvinylpolypyrrolidone]) maybe used
What is the typical fermentation temperature range for the primary fermentation of sparkling wines? Why?
- 14–20°C
- To retain fruit flavours but ensure the temperatures are not too cold for the yeast
Why is the environment stressful for the yeasts during the primary fermentation of the sparkling wines?
Low pH of the juice makes the environment quite stressful for yeast
What is the preferred vessel for the primary fermentation of the sparkling wines? Why?
- Stainless steel
- It allows large volumes to be fermented with temperature control
- Ease of cleaning the tanks before and after fermentation
What kind of yeast is preferred for the primary fermentation of the sparkling wines?
Cultured yeasts that are able to ferment reliably to dryness in high acid and low pH conditions
Do the yeast used for the primary fermentation differ according to the style of the sparkling wine?
Yes, Some strains of yeast can promote certain flavours in the wines, for example thiols or esters. This may be positive in tank method sparkling wines that are based on fruity flavours.
On the other hand, pronounced primary flavours are generally not wanted in autolytic styles of wine as they may compete with the flavours from autolysis so these wines will be made using a neutral yeast that does not enhance these flavours
What type of yeasts are used for the second fermentation of sparkling wines?
It is common to use the same yeast for both the first and second fermentation
Why choosing of the yeast is important especially for the second fermentation of the sparkling wines?
Because during second fermentation, the yeast must be able to start fermenting in alcoholic conditions (10% abv is too high for many yeasts) with low pH, and continue fermenting through low temperatures, in high pressure and with poor availability of nutrients
What is “Prise de mousse’ ?
It is one of the most common cultured yeasts used in sparkling wine production (EC1118)
Is malolactic conversion used during the production of sparkling wines?
Yes, it may be used to reduce acidity in an excessively acidic wine and also can be used to enhance texture
Why are the buttery flavours found on white wines that have undergone malolactic conversion are not typically found on sparkling wines?
Because, diacetyl, which gives the buttery flavour, is metabolised by the yeast during the second fermentation
Why wine should be sterile filtered, if malolactic conversion is not desired?
If malolactic conversion does not take place after primary fermentation, there is the risk that it could take place during the second fermentation. This is problematic for traditional method wines as it can turn the wine hazy, which would be difficult to rectify in the bottle
What is LALVIN DV10?
It is a commercial yeast produced by Lallemand Company LALVIN which claims an ability to work in low pH, high total SO2 and low temperature situations and have neutral character which enables subtle primary fruit to be clearly expressed
Why new oak is used only a very small proportion of the blend in sparkling wines, if used?
Because, the aromas and flavours of oak (vanilla, toast and spice) are usually magnified in the sparkling wines
In which style of sparkling wines, oak is not used?
If the producer is creating a fruity style of wine (e.g. Prosecco or Asti)
What are the blending options for sparkling wines?
- Wines from different vineyard sites
- Wines from different varieties
- Wines from different vintages
- Wines that have undergone different winemaking techniques
What are the purposes of blending in sparkling wines?
- Balance
- Consistency
- Style
- Complexity
- To make rosé wine
- Minimising faults
- Volume
- Price
Which winemaking practices are required after the blending of the wines, before the second fermentation of sparkling wines?
- For traditional method wines, the final blend should be stabilised for tartrates and proteins before being bottled for second fermentation
- For all methods of production for sparkling wine, base wines should be clarified before second fermentation
Where does the second fermentation occur in the Traditional Method sparkling wines?
In the same bottle in which the wine is later sold
What is liqueur de tirage?
It is a mixture of wine and/or must, sugar, cultured yeasts, yeast nutrients and a clarifying agent such as bentonite and/or alginate
What does the amount of sugar in liqueur de tirage depend on?
The degree of effervescence required