WSET Study Guide 2026

For Oloroso Sherry, the base wine is deliberately fortified to 17% abv or higher. This higher alcohol level is toxic to the 'flor' yeast, preventing it from forming. This ensures the wine ages oxidatively from the start, developing the rich, nutty, and complex characteristics typical of the Oloroso style. Fino Sherry is fortified to a lower level (around 15%) specifically to allow the flor to thrive.

The estufagem process heats Madeira wine in tanks or heated rooms, accelerating oxidation and Maillard reactions that produce characteristic caramel, dried fruit, and nutty flavors.

The vast majority of wines produced globally are intended for consumption within a few years of their vintage. Only a small percentage of high-quality wines possess the necessary structure (acidity, tannin, fruit concentration) to benefit from extended aging. Most everyday wines will actually deteriorate if kept for too long, losing their freshness and vibrancy.

The ISO (International Organization for Standardization) tasting glass is specifically designed with standard dimensions to ensure consistency and neutrality in professional wine tasting. Its precise height of 140-150 mm, along with its specific bowl shape and rim diameter, is crucial for concentrating aromas and allowing for objective evaluation of a wine's appearance, smell, and taste.

The bubbles in sparkling wine are created by carbon dioxide gas. This gas can be produced through secondary fermentation, which can occur either in a sealed tank (Charmat method) or directly in the bottle (Traditional method). Additionally, some sparkling wines are made by simply injecting carbon dioxide into still wine, a process known as carbonation.

Vintage Port is aged for approximately 2 years in large oak vats before being bottled, where it then continues to develop for decades.