Lack of Oxygen?

Why are high altitude wines so good?

High altitude wines can be very good indeed but it’s not because of the lack of oxygen. There are a number of factors present in the Andean foothills of Argentina in particular that make this wine special. However, there are also some great high altitude wines being produced in the Elqui and Aconcagua Valleys of Chile and around the cities of Tarija and Potosi in Bolivia.

1. Very broad daily temperature range

The difference between the warmest and coldest temperatures on any given day is called the diurnal range. In Burgundy, France the average diurnal temperature range is around 10 °C while in Salta, Argentina it is often in excess of 20 °C. Generally, the higher you climb the greater the diurnal temperature range.

In the high daytime temperatures found in many parts of the “new world,” the vine producing high altitude wines is working frantically to ripen grapes into high-sugar content capsules. Then as the temperature drops at night, the sugar production is paused and the plant is able to balance the sugar with acids, thereby producing a very balanced structure. The ripening of the grape can carry on for extended periods with this stop-start process, leading to a very well-rounded wine, as long as the agronomist and winemaker know what they are doing of course!

So the more extreme the temperature difference, the greater the sugar content, and the higher the final alcohol content will be. The resulting wine will also have a deep color and plenty of body as will discuss below.

2. High quality sunlight – and lots of it

At altitude in the Andes, sunlight is very high quality indeed, due to the reduced atmospheric interference. Plus it is sunny for a long time each day, especially in the spring and summer growing period, and also over many days of the year. For example, San Juan in Argentina has 320 sunny days a year.

With this intense sunshine comes a defense mechanism whereby the high altitude wine grape increases the thickness of its skin to protect itself from the strong UV rays and shriveling effects. Skins will develop more pigment and tannins, to such an extent that often the grapes will appear black. This extra pigment, tannin, and alcohol mean a fuller bodied wine, with ripe and over-ripe fruit notes and some spices.

3. Steep angle and wind

The steeper angle of the Andes foothills means that bunches of grapes have a direct line of sight with the sun, increasing even further the effects mentioned above. This angle combined the poor quality rocky or sandy soils which increase drainage, mean that vines really have to struggle for nutrients and water – increasing the intensity of the reduced harvests that are produced as a result. As a temperature change happens in the afternoons in this part of the world the wind generally picks up. A moderately windy vineyard is a healthy vineyard as pests and plagues cannot take hold.

The list below can and will be disputed with possibly the new highest vines in the world from the Humahuaca Canyon in Jujuy, Argentina at 3300 meters. 

Top 5 highest vineyards in the world: