ALTERNATIVE VINFICATION METHODS Flashcards
What has more aromatic compounds, the skins or the pulp?
Skins, higher amount of terminals and aroma precursors
Why does skin maceration lower the AC?
Because of the high amount of K (alkaline), it will rise the pH and drop the AC
Name 3 possible advantages of skin maceration
Extraction of aromatic compounds
Increase thiols, terpinols and glutathione (antioxidant naturally found in grapes)
Increase varietal and ‘terroir’ expression
What can you add to the grapes in order to improve free run juice
Pectolytic enzymes. It helps to separate the pulp from the skins and can increase free run juice with 50-75%
Give the amount of hours for a short/classic/long maceration time on the skins
Short: 4-6 hrs
Classic: 8-10 hrs
Long: 12-14 hrs
Which oxidation enzyme are present in grapes for regular grapes and for botrytis grapes?
Regular: tyrosinase
Botrytis: laccase
What is the ideal temperature for skin maceration?
Between 10-15C
Why don’t we use SO2 to protect the grapes at skin maceration? Name at least 2 alternatives
Because SO2 will aid extraction, also from the unwanted parts. Alternatives: CO2, Ascorbic Acid, Dry Ice and in some cases bioprotection
What is the maximum volume of tank in which you can perform carbonic maceration?
100hl
What is the aim of carbonic maceration?
intracellulair reaction within the grapes in an anaerobic environment
Extraction of color and flavour (not tannin!)
Why do we need handpicked fruit for maceration carbonique?
We need whole berries! Also with machine harvested grapes, they already start to oxidise. And fermentation by ‘unwanted’ yeast can already be started.
What happens with the tannin level at carbonic maceration
Reduced up till 30%
Which thiol compound is increased during maceration carbonic?
3-MH, due to reductive environment
Is press juice used for wines made from carbonic maceration?
Yes, mainly to add structure since the tannins are severely reduced
What is the ideal temperature and duration for carbonic maceration?
25-28C for 3-6 days. Temperature is up for discussion. Lot of people go for a colder temperature, around 20C. However this makes the yeast struggle a little bit, which can cause production of H2S and reduction.
