Natural and Human Factors in the Winery that can influence style, quality and price of a wine. Flashcards
Name the five parts of a grape?
Seeds and Stems, Bloom, Pulp, Tannins and skins
What do the seeds and stems contribute to the wine?
Tannins
What is the bloom?
Waxy surface that covers the skins of the grape and contains the native yeast that can be used to ferment the wine.
What does the pulp of the grape contain?
Water, sugar, and acids (tartric acid and malic acid)
What is a tannin?
Chemical compound that tastes very bitter, which falls as the grapes ripen
What does the grape’s skin contain?
High concentration of flavour compounds, also tannin and colour compounds
Why do winemakers use counteractive measures against oxygen during winemaking?
To preserve the primary fruit characteristics.
What are some examples of anaerobic or protective wnemaking? (keeping oxygen at minimum)
using sulphur dioxide, picking grapes at night when cooler, keeping grapes chilled until they reach the winery, filling winery equipment with carbon dioxide or nitrogen
Do wines that have been protected from oxygen during winemaking benefit from oxygen during maturation?
No
What affect does maturing wine in oak have?
Exposed wine to small amounts of oxygen, softens the tannins, creates more complex secondary and tertiary flavors to develop.
Do smaller barriques have greater oxidative effect than larger vessels?
yes
Do wines matured in barrel longer than two years generally go in smaller vessels or larger vessels?
Larger, to prevent too much oxidation.
Why is Sulphur Dioxide used in winemaking?
Acts as antioxidant and an antiseptic
What affect can oak tannins have on a wine?
gives more structure to both red and white wines, increases textural complexity
What are the four factors to consider when choosing which oak to use?
Species and Origin of oak, size, the production of the barrels (such as toasting), age, oak alternatives (staves or chips)
At what age does an oak barrel become neutral?
Fourth usage
When do grapes usually receive their first does of SO2
When they first arrive at the winery
What is free run juice?
When the grapes are crushed upon arrival it produces an initial juice
Are destemming and crushing done for all grapes on reception?
No, machine harvested grapes are already de-stemmed
What is the process that separates the liquid and the solid constituents of the grape?
Pressing
Why is it important to be gentle in both crushing and pressing?
So as not to crush or break the seeds which release unwanted bitter flavours
When do you press for white wines and when for red wines?
White wines are pressed prior to fermentation and reds are pressed after fermentation.
During winemaking, grape juice can also be referred to as xyz?
Must
What are three adjustments that can be made in the winery to improve a wine?
Sugar, alcohol and acid
What is enrichment?
Adding sugar to wine in the form of rectified concentrated grape must (RCGM)
What is chaptalisation?
adding sugar from other sources such as sugar beet
How do you remove alcohol from a wine?
Modern machinery can remove alcohol after fermentation is complete
What is acidification?
The addition of tartaric acid in powder form. Used in warm and hot regions
Deacidification is what?
Removing acid usually in cooler climate regions
What is fermentation?
The conversion of sugar into alcohol and CO2 through the action of yeast
Alchoholic fermentation will not begin until the temp is above what?
5 degrees celcius
Alcoholic fermentation will stop before all the sugar is consumed in two circumstances, what are they?
The yeast runs out of the nutrients it needs or the temperature rises above 35 degrees celcius
If the winemaker wants to stop fermentation, how do they do so?
By killing or removing the yeast (adding sulphur or grape spirit to kill or filtration to remove)
If a winemaker wants to remove the yeast, what steps do they take?
They stop fermentation by chilling the wine below 5 degrees celcius and then they filter out the yeast