Sparkling winemaking Flashcards
What is a typical climate for growing grapes for sparkling wines?
Cool climates where grapes struggle to ripen - to give just-ripe flavours, retain high acid, and low potential sugar (9-11%)
What is the link between cool climate and acid levels?
Grapes will metabolise acid as they ripen, rather than stored sugar. Therefore, cool climates, or a diurnal swing to cool, will help retain acid as it slows the metabolism of the vine
what examples of cool climates are there?
greater latitudes - Chapagne, England, Tasmania
Coastal influence - Sonoma
High altitude - Trentodoc
What sparking wines are made in warmer climates?
as grapes have lower acidity and riper fruit flavours, they are better suited to:
- tank fermented aromatic
- short matured, minimal autolysis for transfer/traditional
How is a sparkling vineyard typically managed?
higher yields help to achieve higher acid, lower potential alcohol and delicate flavours
trellising should maximise clean healthy fruit to minimise disease
harvest early to target flavour profile above, and minimise fungal disease from autumnal weather
Do not pick unripe grapes - these flavours can be more prominent during maturation
how are grapes usually harvested?
cheaper wines - machine harvest to :
- More grapes can be harvested quickly at the same time
- option for night harvest to keep grapes cool and minimise the impact of phenolic extraction and oxidation
- may need sorting
Hand pick if:
- required by law
- whole bunch pressing required
- hand sorting for disease/ripeness in poor years
What are the key steps in traditional method sparkling winemaking?
- Pressing, normally whole bunch
- clarify (casein, gelatine or PVPP)
- primary fermentation
- maturation (optional), oak or lees
- blending (sites, vintages, etc)
- stabilisation (protein, tartrates)
- second fermentation
- lees ageing
- riddling and disgorgement
How are sparkling grapes pressed?
Whole bunch pressing for premium wines:
- stems create channels for juice, so lower pressure
- must is low in solids and phenolics as a result
Press quickly to minimise maceration and skin phenolic extraction
What presses are used for whole bunch pressing?
Basket press or pneumatic press
What are later press fractions used for?
Higher amounts of phenolics, solids and pH can result in wines that are faster maturing. These can be used for wines made for immediate consumption
What agents are used to clarify sparkling wine must?
Casein, Gelatine or PVPP
What are the typical requirements for primary fermentation?
- 14°C to 20°C
- Stainless steel
- Cultured yeast (Neutral, high acid)
- optional: Malolactic conversion can reduce acid and add texture. Diacetyl flavours are removed in secondary fermentation
What are the benefits of malolactic conversion in a base wine?
increases stability - reducing likelihood of cloudiness later on
reduces acid
Increases texture
What maturation of base wine may take place?
limited oak
leave on the lees (e.g. Pelores, NZ they stir the lees)
What reasons can a base wine be blended?
- Balance
- Consistency
- Style
- Rosé
- Complexity
- Minimisation of faults
- Volume
- Price
Give an example of balance blending?
Pinot Noir brings body, chardonnay brings acidity. This could also be done with cooler/warmer sites
Give an example of consistency blending?
NV Champagne needs to be consistent between years so that consumers know what a brand style is
Give an example of style blending?
Cheaper wines may have more ripe fruit and less acidity
Premium wines may be styled for ageing
Give an example of complexity blending?
blending across vintages/ sites/ grape varieties/ oak maturation/ age
Give an example of blending for volume?
smallholdings can buy in wine to blend
Give an example of price blending?
blend a higher yield/cheaper variety - Meunier in Champagne
What is added to base wine for second fermentation?
Liqueur de tirage is a mixture of:
- wine/must
- sugar (24g/l adds about 1.5%)
- cultured yeast
- yeast nutrients
- clarifying agent (bentonite, alginate)
How much sugar creates a given level of pressure?
24g/l will create 6 atmospheres of pressure
What is the french term for secondary fermentation?
Prise de mousse
What are the characteristics for the cultured yeast used for secondary fermentation?
- commence fermentation at 9.5% to 11%
- temperature of 16°C
- pH below 3
- withstand high pressure
- flocculate readily
what steps are there in secondary fermentation?
Add liqueur de tirage, bottle, seal with a crown cap
store horizontally at 10-12°C for at least 4-6 weeks
How long before lees ageing impacts wine?
Stability and anti-oxidant properties will be from day 1.
Detectable aromas take about 9 months minimum
What is autolysis?
enzymatic breakdown of yeast cells
lasts between 4-5 and 10 years
Anti-oxidative
The longer a wine is held on the lees, typically the quicker it should be drunk after disgorgement
What is the French name for riddling?
remuage
What are riddling options?
gyropalette (3-4 days)
pupitres hand riddling (8 weeks)
how are wines disgorged?
- chill to 7°C to reduce gushing
- immerse neck in brine to freeze sediment
- remove crown cap and basket
- add liqueur d’expedition
- cork
What is in the dosage?
wine and/or RCGM
what sugar levels classify sparkling wines?
0-3g/l Brut Nature/ Zero dosage
0-6 g/l Extra Brut
0-12 g/l Brut
12-17 g/l Extra-sec/ extra dry
17-32 g/l sec/ dry
32-50 g/l demi-sec/ medium dry
50+ g/l Doux/Sweet
all +/- 3 g\l
What are the steps in transfer method?
- no fining agents in the liqueur de tirage
- chill wine to 0°C
- open wine and transfer under pressure to large tank.
- sweeten
- SO2
- filter and bottle
Set out the ancestral method and how else is it known?
- bottle partly fermented wine and allow to ferment in the bottle
- sediment will remain in the bottle
- may have residual sugar and lower pressure
Also called Pétillant natural, or Pet Nat
How is the tank method also known?
Cuve Close
Charmant
Martinotti
What style of wines are tank fermented?
primary aroma preservation
no autolytic character
semi-aromatic, or aromatic
What are the key steps in the tank method?
- first ferment in tank between 16°C-18°C
- add sugar and yeast and transfer to pressurised tank
- stop fermentation by cooling to 2°C-4°C
- cold stabilise tartrates
- filter, adjust SO2
- bottle under pressure at -2°C using a counter pressure filling system using CO2
Option 1 - filter and bottle directly
Option 2 - mature on lees in the tank
What are the key steps to the Asti method?
- ferment in one step
- use a reinforced tank
- mid-ferment, stop the escape of CO2
- chill wine once target levels are reached and filter under pressure
How is carbonation achieved?
- inject carbon dioxide under pressure
- suitable for aromatic or fruity wines
- works better for pétiiant, or lower pressure sparkling wines
What closure options are there?
Cork - 31mm agglomerate with discs of natural cork
crown cap - particularly used in Pet Nat
What is a common cultured yeast used in traditional method
EC-1118
