Winemaking and maturation Flashcards
What are the constituent parts of the grape ?
Seeds and stems
Skins
Bloom
Pulp
What is the bloom of the grape ?
The waxy surface that contains the yeast.
What is the most abundant acid in the grape pulp ?
- Tartaric acid
2. Malic acid
What is the most commonly used antioxidant ?
Sulfur dioxide
What are the beneficial properties of SO2 ?
It is both an antiseptic (against unwanted strains of yeast and bacteria) and an antioxidant.
What is the diference bewteen a barrique and a pièce ?
The barrique is of 225 litres and the pièce of 228.
What is the difference between enrichment and chaptalization ?
Enrichment is carried out with RCGM, Rectified Concentrated Grape Must, where as chaptalization is carried out with suger from other sources than grapes, such as sugar beet.
What temperature span does alcoholic fermentation take place in ?
Normally between 5 and 35 degrees.
What are the advantages of fermentation at lower temperatures ?
Avoids the loss of the most volatile aromas (floral, often)
Can encourage the development of fruity flavours in white wines
How can MLF be encouraged ?
By raising the temperature of the wine after the alcoholic fermentation and by not adding sulphur dioxide.
What is the difference between the fine and the gross lees ?
The gross lees are particles of dead yeast cells and grape fragments that fall to the bottom of the fermentation of storage vessel within a few hours and can cause unpleasant aromas, if not removed.
The fine lees settle more slowly, throught the sine maturation process.
Some winemakers may choose to keep the white wine in contact with the fine lees during pre-bottling maturation.
In order to benefit from medium to long-term ageing, what does a wine need to contain ?
Sufficient levels of tannin, acidity and/or alcohol, as well as flavours that will develop in an interesting way.
What is free run juice ?
Crushing breaks the skins of grapes without breaking the seeds and liberates a quantity of juice known as free run juice.
How is wine clarified ?
Sedimentation (can be accelerated by centrifugation)
Fining
Filtration
What is racking ?
When the gross lees have settled, the wine is slowly and gently pumped into a different vessel (leaving the sediment behind) : may be repeated.