How Prosecco is Made

Here's an overview of how Prosecco is made:

1. Harvesting

  • Grapes: The primary grape used is Glera, though other varieties like Verdiso, Perera, and Bianchetta can be blended in small quantities.

  • Timing: Grapes are usually harvested early to retain their acidity, which is crucial for sparkling wines.

2. Pressing

  • Destemming and Crushing: The harvested grapes are destemmed and gently crushed to extract the juice.

  • Must: The juice, known as must, is then clarified to remove any solids.

3. Fermentation

  • First Fermentation: The clarified must undergoes the first fermentation in stainless steel tanks at controlled temperatures. This process converts the grape sugars into alcohol and results in a still wine.

  • Base Wine: The result of the first fermentation is a base wine, which is then filtered and stabilized.

4. Secondary Fermentation (Charmat Method)

  • Tank Fermentation: The base wine is transferred to a pressurized tank. Sugar and yeast are added to initiate the second fermentation.

  • Carbonation: During this fermentation, carbon dioxide is produced, which dissolves into the wine, creating bubbles.

  • Temperature Control: The temperature is carefully controlled to ensure the process is slow and steady, enhancing the wine's flavor and aroma profile.

5. Filtration and Bottling

  • Filtration: After the secondary fermentation, the wine is filtered to remove the yeast sediment.

  • Bottling: The filtered sparkling wine is then bottled under pressure to retain the carbonation.

6. Aging

  • Resting: Prosecco typically does not require long aging. It is usually ready to be enjoyed soon after bottling, although some premium versions may benefit from a short period of aging.

Ever Wonder? How is Sparking Rosé Made?


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Sparkling rosé is a wonderful treat that is especially enjoyed during warm summer months.

Sparking rosé is versatile, aesthetic appealing, sophisticated, light and balanced in flavor, and suitable for various social settings and occasions. These factors combine to make sparkling rosé a popular choice among wine drinkers.

There are two methods of producing a sparkling wine. The key difference lies in where the secondary fermentation occurs:

Traditional Method (Méthode Champenoise):

  • Primary Fermentation: Red wine grapes are crushed, and the juice (must) is extracted and left in very brief contact with the skins. This give the base rosé wine its pale pink color.

  • Secondary Fermentation: Sugar and yeast are added to the base wine in the bottle. Just as in the Primary Fermentation, this new yeast and sugar interacts to produce alcohol and carbon dioxide (CO2), which forms the bubbles.

  • Aging on Lees: After fermentation is complete, the wine is aged on its lees (dead yeast cells) to develop flavor complexity. This process can take months to a few years.

  • Riddling: The bottles are gradually turned and tilted upside down to collect the lees in the neck of the bottle.

  • Disgorging: The neck of the bottle is frozen and the plug of frozen lees is removed.

  • Dosage: A small mixture of wine and sugar may be added to adjust the final sweetness of the sparkling wine.

  • Corking: A cork is inserted, the bottle is sealed and it is ready to be sold.

Tank Method (Charmat Method):

  • Primary Fermentation: The base wine is made by fermenting rosé wine in a tank, similar to still wine production.

  • Secondary Fermentation: The wine is transferred to a pressurized tank, along with sugar and yeast. The secondary fermentation occurs in the tank, producing the bubbles.

  • Filtration: Once fermentation is complete, the wine is filtered to remove the yeast and any other sediments.

  • Dosage: A dosage (a mixture of wine and sugar) may be added to adjust sweetness.

  • Bottling: The wine is bottled under pressure to maintain the carbonation.


Ever Wonder? Where Does the Color of a Wine Come From?

Wine can be beautiful shades of yellow, gold, pink, purple or ruby in color with pale, medium and deep intensities. But, where do all these beautiful colors come from?

The final color and hue of a wine comes down to how the various types of wines are made.

  • To produce white wines, the green grapes are pressed to extract the juice from the grapes for fermentation

  • For Rosé wines, red/purple grapes are pressed and the juice is briefly left in contact with the skins and seeds of the grapes before fermentation

  • With red wines, the grape juice, skins and seeds all stay together for fermentation

The key here is that all juice from grapes is essentially clear to begin with. It’s the skins of the grapes that imparts the final color to the wine.

You can actually produce a white wine from a red wine grape - you simply don’t allow for any contact between the clear grape juice and the skins of the red/purple grapes. So, you basically follow the white wine-making process but using red grapes. One of the most famous white wines that is made from red grapes is Champagne. Traditional Champagne is made from two red grapes (Pinot Noir and Pinot Meunier (Pee-noh Mehr-n'yay)) and one white wine grape (Chardonnay). Champagne is a white sparkling wine because the clear juice from the Pinot Noir and Pinot Meunier grapes are combined with the clear juice from the Chardonnay grape prior to fermentation with no skin contact.

So, again, a wine’s color is all about how long, if at all, the juice of the grapes is left in contact with the skins.

By the way, there is another color of wine and it’s orange. We’ll look into that next time. Cheers!

Why Do Winemakers Blend Viognier with Tannat?

Winemakers sometimes blend Viognier with Tannat. But why would they combine a white wine with a red wine?

Blending Viognier with Tannat actually provides several benefits to winemakers:

  1. Enhanced Color: Tannat is known for its deep ruby red color. Adding Viognier to Tannat actually acts to brighten the overall color of the wine and make it more visually appealing.

  2. Greater Structure and Complexity: Blending Viognier with Tannat helps soften the wine and balance it out, providing more even structure and greater complexity.

  3. Enhanced Aromas: Viognier is highly aromatic, providing floral and fruity notes. Adding a small amount of Viognier to Tannat enhances the aroma of the wine.

  4. Better Balance: Viognier tends to have higher acidity compared to Tannat. Blending in just a small amount of Viognier will raise the acidity level giving a brighter and a more balanced final product.

  5. Softening Tannins: Tannat is known for its bold tannins, which can sometimes be too overpowering. By blending Viognier, which has softer tannins, winemakers can reduce the harshness of Tannat, resulting in a smoother wine.

  6. Market Appeal: Viognier is a popular grape variety, especially in certain markets. Blending it with Tannat can help increase the market appeal of the wine, making it more attractive to consumers who may be drawn to the unique characteristics of Viognier.

Overall, blending Viognier with Tannat allows winemakers to create a wine that is well-balanced, complex, and appealing to a wider range of consumers.

Look for a review of this Alto de la Ballena Reserve Tannat - Viognier in the next Behind the Cork™ Wine of the Week. Cheers!

Tannin Management in Winemaking is an Important Factor in Producing a Balanced Wine

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The major characteristics of a wine include alcohol level, acidity and pH, residual sugar and its level of tannin.

Tannin is manifested in food and drink as bitterness and astringency. Examples include strong tea or coffee, dark chocolate and, of course, wine. And, red wine, in particular.

Let’s focus here on the characteristic of tannin in wine.

To get very briefly technical, one of the defining characteristics of tannins is that they combine with proteins and precipitate, or extract them, from solutions. When these tannin proteins are precipitated from the saliva in your mouth, it ceases to be an efficient lubricator of your mouth and tongue, creating the astringent sensation we most commonly associate with tannins.

Tannins in wine can come from five sources: grape skins, seeds, stems, oak.

Good tannin management by wine makers avoids harshness or bitterness in the final wine. Understanding these factors helps winemakers create wines with balanced tannin levels that contribute to the wine's structure, mouthfeel, and aging potential.

The amount of tannins in wine can be influenced by a number of factors. Here’s a top-level summary:

The Grape, its Seeds and the Stems

  • Tannin comes from the grape’s skin, its seed and the stems

  • Different grape varieties have differing levels of tannins

    • Red wine grapes contribute the highest levels of tannin

    • Tannat, Nebbiolo and Cabernet Sauvignon are known for having especially high levels of tannins

      • Tannat is known to produce wine with big tannin. This is partly because the Tannat grape has very thick skin but also due to the fact that the Tannat grape is unique in that it has 4-5 seeds (pips) per berry while most other wine grapes only have 2-3

  • Winemakers must consider the inherent characteristics of the grape variety they are working with to achieve the desired balance of tannins in the finished wine

Growing Conditions in the Vineyard

  • Winemakers base tannin management in the vineyard on many factors including the ripeness of the grapes, the thickness of their skins and the desired wine style they want to produce

  • Tannins in the skins protect the grapes from the sun. Skin tannins, in part, function as a grape’s natural sunscreen. So, the more light that reaches a grape’s surface (or the more intense that light is), the more tannins the skins produce

  • Leafing strategy on the grape vine is a big factor for building or reducing tannins. The more shade the leaves provide to the grapes, the fewer tannins are formed

  • Winemakers monitor the grapes' tannin levels regularly and harvest at what they determine is the optimal time for their desired wine

Winemaking Practices in the Winery

  • Maceration time, or the amount of time red wine spends in contact with its skins during winemaking, has an important influence on the extraction of tannin

  • Tannins, especially seed tannins, require alcohol for extraction, and the rate of tannin extraction increases as alcohol concentration rises in the wine during fermentation

  • Warmer fermentation temperatures (80° F and higher) can increase tannin extraction

  • “Punch-down” is a very gentle extraction technique where the winemaker carefully pushes the grape skins that rise to the top during fermentation back down into the liquid or the ‘must’

  • “Pump-overs” offer a slightly more effective method for tannin extraction. Here, the liquid at the bottom of the fermenting tank is drawn off and pumped back over the grape skins that float in the liquid

  • Aging wine is oak barrels imparts tannin

  • The type of oak used to make the barrels is also a factor. Choices include French oak, American oak and Hungarian oak

    • French oak is known for its ‘elegant’ tannins that result in wines with smoother mouthfeel

    • American oak is known for pronounced tannin and slightly ‘coarser’ texture

    • Hungarian oak tends to be somewhere in between French and American oak by imparting moderate tannin levels

  • New oak barrels (ones that have never been used) impart the greatest amount of tannin to a wine

  • New oak is used often only with a wine that has sufficient weight and power that won’t be overwhelmed by the oak’s own tannins

  • As a wine ages, tannins can precipitate out of the wine. However, it's essential to note that not all wines benefit from extended aging, and the effects of aging on tannins can vary depending on factors such as grape variety, winemaking techniques, and storage conditions