Terpenes
A class of aromatic compounds found naturally in grape skins and juice, responsible for floral, citrus, and spice aromas in aromatic grape varieties.
In depth
Terpenes are primary aroma compounds — they originate directly from the grape itself rather than from fermentation or ageing. The most important wine terpenes are linalool (floral, lavender), geraniol (rose), nerol (citrus), and citronellol (lemon). These compounds are particularly abundant in aromatic varieties such as Muscat, Gewurztraminer, Riesling, Viognier, and Torrontés.
Terpenes exist in two forms: free (immediately volatile and aromatic) and bound (attached to sugars and non-aromatic until hydrolysis releases them). This explains why some Rieslings develop stronger floral and petrol aromas with age — bound terpenes are gradually released.
For the exam, terpenes are the key explanation for why aromatic varieties smell as they do. When asked to describe the aromatic profile of Gewurztraminer (rose, lychee, ginger) or Muscat (orange blossom, grape), the underlying answer is terpene concentration from the grape variety itself.
Related exam topics
Frequently asked questions
- Which grape varieties are highest in terpenes?
- The most terpene-rich varieties are those of the Muscat family (Muscat Blanc à Petits Grains, Muscat of Alexandria), followed by Gewurztraminer, Riesling, Viognier, Torrontés, and Albariño. These varieties are described as "aromatic" precisely because of their high terpene content.
- Are terpenes primary, secondary, or tertiary aromas?
- Terpenes are primary aromas — they come directly from the grape variety itself, not from fermentation or ageing. They fall under the "varietal aromas" category in the Systematic Approach to Tasting.
Practise questions on this topic
Use Vinlecta to practise exam-style questions that test your knowledge of terpenes and related topics.