Fortification
The addition of grape spirit (neutral alcohol distilled from wine) to a wine during or after fermentation, raising its alcohol content to 15–22% ABV and — if added during fermentation — preserving residual sugar.
In depth
Fortification transforms a normal still wine into a fortified wine. The timing of spirit addition is critical to the final style:
Added during fermentation (Port, Banyuls, Vin Doux Naturel): the added spirit kills the fermenting yeast before all the sugar is consumed, leaving the wine sweet. The earlier the addition, the sweeter the wine. Port is fortified at about half its fermentation — when alcohol reaches around 6–8% ABV, the spirit is added to reach a final 19–22% ABV.
Added after fermentation is complete (Sherry, Madeira base wines): the wine ferments to dryness first, then spirit is added to raise alcohol to 15–22% ABV. The wine is dry to start; sweetness in styles like Cream Sherry or Malmsey Madeira comes from blending with very sweet wines or grape juice (PX in Sherry, concentrated must in Madeira).
The spirit used is typically grape-derived neutral spirit (aguardente in Portugal, holandas or mistela in Spain) — not vodka or grain spirit. This maintains the wine character.
At Level 3, candidates must distinguish between: mid-fermentation fortification (Port) and post-fermentation fortification (Sherry), and explain the sweetness implications of each.
Related exam topics
Frequently asked questions
- Why is Port sweet while Fino Sherry is dry, even though both are fortified?
- The timing of fortification determines sweetness. Port is fortified during fermentation — the spirit kills the yeast before all sugar is converted, leaving significant residual sugar (80–120 g/L for Ruby Port). Fino Sherry is fortified after fermentation is complete — the wine is already dry when spirit is added. The fortification simply raises the alcohol level; it does not add sweetness.
Related terms
Practise questions on this topic
Use Vinlecta to practise exam-style questions that test your knowledge of fortification and related topics.