Section 2: Factors affecting wine and style and quality Flashcards
What are vines?
A vine is a plant that can live for 60 years or more. Each variety has different characteristics that affects the appearance as well as their tastes and flavours.
The parts of a grape?
Skins: Contains high of flavours, colour and tannins.
Seeds and stems: High levels of tannings.
Pulp: Contains acids and flavours. Skins of black grapes that give red wines their colour.
The 4 stages of grape formation?
Flowering
In spring the vine starts to grow and produces clusters of flowers. Each cluster will become a bunch of grapes. Vines rely on the wind to pollinate their flowers.
Fruit set
Once pollinated the flower starts to grow seeds and begins to swell. The newly formed grapes are small, hard, dark green and unpleasant to taste. The flower has become a grape that will grow and ripen during the summer months.
Véraison
Mid-summer ripening starts with véraison which is when the grapes start to lose their dark green colour. White grapes become golden and black grapes become red and purple.
Ripening
At the start of the ripening grapes have very high levels of acid. During the ripening the acidity drops and the amount of sugar rises. In black grapes tannins develop in the skins. If they are unripe they can taste bitter.
3 ways used to make sweet wines
Extra ripening
Grapes that are left past the point when they are normally harvested. The grapes develop exaggerated ripe aromas and higher levels of sugar because of the water content that evaporates. Commonly used to make sweet wines.
Botrytis/Noble rot
Botrytis is a fungus that can grow on ripe grapes causing noble rot. It makes tiny holes in the skin which causes the water inside the grape to evaporate. Ideal conditions are needed. Damp misty mornings allow the growth and spread of the fungus. Dry afternoons limit the growth of the fungus. Grapes affected by noble rot are nearly always used to make sweet wines.
Frozen grapes
Healthy grapes are left on the vine through autumn to winter. When the frozen grapes are pressed, the ice crystals along with the skins can be separated from the small amount of remaining unfrozen liquid.This liquid contains high concentrations of acids, sugars and flavours. The result is known as Icewine.
When are the growing seasons in the northern and southern hemisphere?
The growing season in the northern hemisphere runs from April to October, in the southern hemisphere from October to April.
What are the 3 climates?
Cool: Average growing season temperature of 16.5C or below
Moderate: Average growing season temperature of 16.5C to 18.5C
Warm: Average growing season temperature of 18.5C to 21C
What latitudes are vineyards located between?
Most vineyards are located between 30 to 50 north or south of the equator.
What is a hot vintage?
Growing season hotter than normal and too much sunlight. Grapes can be damaged by sunburn and develop uncharacteristic dried fruit aromas. When short of water vines shut down to protect themselves and the grapes do not develop.
What is a cold vintage?
Growing season colder than normal and less sunlight. Vines may struggle to ripen, acid levels will be too high and sugar too low. The grapes may also struggle to develop their signature aromas.
How can altitude influence a vineyard?
A vineyard located at a higher altitude will always have a cooler climate than a vineyard at the same latitude but with a lower altitude.
How can seas influence a vineyard?
Regions with warm climates close to the sea can benefit from cool ocean currents. Northern Europe benefits from warming influences of warm ocean currents.
How can rivers influence a vineyard?
Rivers take longer to warm up and cool down than land. In Autumn, rivers are warmer than the surrounding land. They provide warmth in cooler regions and help extend the growing season. They can also reflect sunlight and protect against frost.
How can air influence a vineyard?
Cool air from seas and mountains has a moderating effect on the climate. Warmer costal areas benefit from the cool winds blowing from the cold seas. Cold air from mountains can move down to lower altitudes at night, cooling down warmer vineyards where heat can build up during the day.
How can clouds, fog and mist influence a vineyard?
Clouds can block sunlight to a vineyard making grapes longer to ripen. This is a very important moderating factor in some warmer Australian regions.
Fog cools down a vineyard and provides a very important moderating influence in coastal regions of California and Chile.
Mist that forms near rivers during the morning in autumn are essential for the development of botrytis/noble rot.
How can Mountains influence a vineyard?
Mountains can act as a barrier from clouds, rain and cold winds. The protection given by mountains results in sunny summers, dry autumns and an extended growing season
