D1-VINI Quiz on Extraction to Maturation for Red Winemaking Flashcards
In what kind of solutions is tannin more soluble?
a. more soluble in alcoholic solutions
b. more soluble in azeotropic solutions
c. more soluble in aqueous solutions
a. more soluble in alcoholic solutions
In what kind of solutions are anthocyanins more soluble?
a. more soluble in alcoholic solutions
b. more soluble in azeotropic solutions
c. more soluble in aqueous solutions
c. more soluble in aqueous solutions
Which factors affect extraction of anthocyanins, tannins and flavours from the grape skins?
a. Time on skins
b. Management of the skins and juice
c. Exposure to SO2
d. Ageing on the lees
e. Temperature
f. The medium in which the extraction is taking place
a. Time on skins, Generally, the longer the juice/wine remains in contact with the skins the greater the extraction.
b. Management of the skins and juice
e. Temperature, Higher temperatures result in greater extraction.
f. The medium in which the extraction is taking place. For example, tannins are most soluble in alcoholic solutions (e.g. wine), whereas anthocyanins are most soluble in aqueous solutions (e.g. grape must).
Which wine component is the source of colour in young red wines?
Anthocyanins
Which winemaking processes can help promote colour stability in red wines?
a. Micro-oxygenation
b. Barrel ageing
c. Lees ageing
d. Addition of SO2
a. Micro-oxygenation
b. Barrel ageing
Gentle oxygenation of the wine can help promote colour stability.
Which wine component found in the skins of black grapes make them less vulnerable to oxidation than white grapes?
Phenolics
How long does pre-fermentation maceration (cold soaking) often last for red wine? Give your answers in numerals.
3 to 7 days
Select two alternative terms for cold maceration from the options below.
a. Saignée
b. Pre-fermentation maceration
c. Thermovinification
d. Flash détente
e. Cold soaking
b. Pre-fermentation maceration
e. Cold soaking
If a winemaker chooses to use flash détente or thermovinification when producing red wines, what quality levels of wine will they likely be aiming for?
a. Inexpensive
b. Mid-level
c. Premium
d. Super premium
a. Inexpensive
b. Mid-level
What is the name of the oxidative enzyme produced by grey rot in botrytised grapes that the high temperatures used in flash détente and thermovinification can help denature?
Laccase
What are the French names for the following cap management techniques:
- Punching down
- Rack and Return
- Pumping over
- Punching down -> Pigeage
- Rack and Return -> Delestage
- Pumping over -> Remontage
Explain the key differences between carbonic maceration, semi-carbonic maceration and whole bunch fermentations. Think about the following when answering:
- What are the objectives of each form of fermentation?
- What flavours/aromas might be produced by each technique?
- What style of wine might a winemaker be aiming for with each technique?
- What are the cost implications for each technique?
For whole berry/bunch fermentations there are some similar objectives. The grapes are picked by hand as they need to be intact (whole bunch) and put into a vessel i.e. stainless-steel tank. Carbon dioxide is added to exclude oxygen. The anaerobic environment created converts some of the sugars in the grapes to alcohol without any yeast being added and is called intracellular fermentation. The malic acid present in the grape is broken down to ethanol, reducing the levels of malic acid by up to 50%, lowering the overall acidity and raising the pH of the wine. Glycerol levels increase, and some distinct aromas/flavours are created in the wine.
Carbonic maceration is carried out on whole, intact bunches that are put into vessels and carbon dioxide to remove all oxygen. Intracellular fermentation begins and when the alcohol level in the grapes reaches 2%, the grapes split and release their juice. The juice is drained off and the skins pressed. Both components are blended back, and the fermentation continues off the skins.
The aromas/flavours associated with carbonic maceration are kirsch, banana, bubble gum (boiled sweets/confected) and cinnamon.
The style of wine is fruity with low tannin and for early consumption.
There are little cost implications with this technique and the wines are usually unoaked, so costs are minimal.
Semi-carbonic maceration varies slightly to carbonic maceration as the tank is not filled with carbon dioxide. The tank is filled with whole, intact bunches but it is the weight of the grapes that crush the berries at the bottom of the vessel, releasing juice. Cultured yeast can be added at this point, but it is traditionally ambient yeast. With this the fermentation starts, producing carbon dioxide which is trapped in the vessel, the intact berries undergo intracellular fermentation. Once these berries split i.e. when they reach 2% alcohol, the juice is drained, and the grapes are pressed. Both components are blended back, and the fermentation continues off the skins.
For more complex styles of wines, the fermentation may continue on the skins to add the desired tannin, colour and body to the wine. Cap management techniques will be used to extract the components from the grapes.
Depending on how much or little cap management is carried out, the wines will be more or slightly less fruit driven, displaying typical fruit flavours depending on the grape variety.
The style is like carbonic maceration but if there is more skin contact during fermentation and cap management, the tannins will be higher and the colour more intense.
There are little cost implications for this process, unless the wines undergo some post fermentation maceration and oak maturation.
Whole berries/bunches with crushed fruit will undergo some intracellular fermentation but no carbon dioxide will be added to exclude oxygen. The level of associated ‘carbonic’ aromas will be less or more, depending on the proportion of whole bunches to crushed fruit there is in the tank. Similar to semi-carbonic maceration, cap management techniques will be used to extract colour and tannin. The style of wine varies as the proportion of whole bunch vs. crushed fruit is variable.
The cost implications are typical and will increase depending on the level of cap management, post fermentation maceration and oak maturation is carried out.
Describe the process of post-fermentation maceration and identify the likely style, quality and price of wine a winemaker would be looking to achieve when using this method.
Post fermentation maceration involves leaving the finished wine on skins after fermentation for a period of time, normally a few days to a few weeks. During this period further tannin is extracted and the polymerisation of tannins occurs which adds positively to the wines structure and texture, while improving the ageing potential. This technique is really only suitable for premium red wines as the quality of the fruit needs to be excellent to start with and the wine style produced will have potential for ageing. The cost associated with this technique is high due to tank space being used and the time taken to manage the wine.
At what percentage abv would the fermenting must of a red wine be pressed when it has undergone carbonic maceration? Type your answers in numerals.
2% ABV
Fill in the blanks:
Malolactic conversion is [almost always or rarely] carried out for red wines. It is often felt that malolactic conversion in [stainless steel or oak barrels] can lead to a better integration of oak characteristics during maturation.
almost always
oak barrels
