Ice Wine: A Rare and Sweet Oenological Jewel

Ice wine is a unique and highly sought-after type of wine. It is made under specific climatic conditions that do not occur every year, requiring strict quality controls. These wines are known for their deep, sweet aromas, intense acidity, and smooth taste. They are considered miraculous due to the extreme conditions needed for their production. Ice wines are rare, extremely sweet, and of high quality. Their origin traces back to Germany, where they are known as "eiswein."

Typically, ice wines are made from white grape varieties like Riesling, Vidal, or Gewürztraminer, although red varieties like Pinot Noir and Cabernet Sauvignon are also used. The production of ice wine does not depend on a specific grape variety but rather on a particular type of viticulture and winemaking process. Grapes must be hand-harvested while frozen on the vine and pressed with ice crystals intact. This process results in a high concentration of sugars and acids due to dehydration, enhancing the extraction of aromatic and flavorful compounds.

In some cases, the grapes are not only frozen but also overripe because they remain on the vine longer than usual, waiting for the right climatic conditions. This delay can sometimes last for months. For the grapes to freeze, the ambient temperature must stay around -7 to -8 degrees Celsius for several days, but not drop below -13 degrees Celsius, as this would make it impossible to produce wine from fully solidified grapes. At these temperatures, the water in the grape freezes, allowing for the extraction of a highly concentrated juice.

It is crucial to press the grapes immediately after harvesting before they warm up and the ice crystals melt, which would render them unusable. The pressing is done using special high-pressure presses, and the resulting must is a natural concentrate with over 28% sugar by weight and high acidity. As the pressing continues and thawing increases, the sugar-acid ratio decreases, and only a small proportion of the must can be used.

The difficulty and rarity of producing ice wine, along with the specific climatic conditions required, justify its high market price. Ice wines are considered "oenological jewels" by many experts. These wines are produced in cold regions of countries with low temperatures, including Canada, the United States, Germany, Austria, Switzerland, and Luxembourg. In Spain, ice wines have been successfully made in Rueda with Verdejo grapes and in Rioja with Tempranillo and Garnacha varieties.

The origin of ice wine dates back to the 18th century in the Franconia region of northern Bavaria, Germany. Due to necessity, when grapes froze, winemakers decided to use the frozen grapes rather than lose the harvest. This resulted in a highly appreciated, full-bodied, and sweet wine that was well-received and became a success, prompting continued production. Despite significant grape losses due to fermentation issues at the time, the success of their perseverance led to a new business model through the costly ice wine, which gained popularity and demand.

Since then, especially from the Napoleonic era, this enological masterpiece has spread to other countries with similar climatic conditions, which began producing wines using the same method. Ice wine demonstrates that vineyards can thrive in the most adverse conditions and extreme situations worldwide, as long as they can access certain amounts of water, even if it freezes.

Currently, the European Union recognizes ice wine as such when made from grapes that were frozen on the vine at the time of harvest and pressing. All grapes must come from a recognized region, and the minimum alcohol content must be 15%, without specifying a maximum level.

Cryoextraction, or cold extraction, is a process where grapes are artificially frozen and pressed, usually to produce ice wine artificially. This method yields sweet or semi-sweet white wines, although it is increasingly used for producing dry and aromatic white wines. Winemakers attempt to recreate the natural conditions of authentic ice wine production. Selected grapes are subjected to sub-zero temperatures (-6 or -7°C) and pressed while still frozen. Although this enological technique produces interesting wines, the European Union does not allow them to be labeled as "ice wines" since the grapes were frozen artificially.