The nose on your favorite bottle of Syrah is, in all likelihood, among the most memorable aspects of the wine and part of what makes it stand out to you. Wine is defined more so by its aromas than any other alcoholic drink.
A number of compounds and factors play into why a glass of wine smells the way it does -- the region where the grape is grown, the vintage, the esters and lactones within the fruit. The are also terpenes in wine, and in many types of wine, these terpenes have a major impact on the nose and on the overall flavor profile.
Let’s dive into which terpenes are common in wine, and how they impact the overall presentation and experience of the bottle.
What are the common terpenes in wine?
- Geraniol: This terpene gives white wines, in particular, their rose-y aroma. Geraniol is found in bound grapes that have passed through the fermentation process. Some white wine varietals will contain higher levels of this terpene due to natural factors such as their region, or terroir, and human-controlled factors like the fermentation process.
- Linalool: If you catch a whiff of lavender upon opening up a bottle, odds are there is linalool present in the grape. You may notice this in Chenin Blanc, for instance, as well as varietals of Muscat grapes, which typically have a high content of both geraniol and linalool.
- Citronellol: Citrus-y aroma common in white wines like Riesling, Chenin Blanc, Chardonnay, and Viognier.
- a-terpeniol : Also known as Nerol, you’ll find a-terpeniol most commonly in varietals of Torrontes, Muscadet, Pinot Grigio, and Semillon.
Breaking down terpenes’ impact on the flavors of wine
Experienced wine connoisseurs are quick to point to the three flavor groups that define a wine: These are Earth, Spice, and Fruit/Floral/Herbal. When it comes to terpenes, we’re talking about the latter category.
Terpenes bring the entire trifecta of this group to life in a good bottle of wine, complementing an herbal, resine-y hit on the front end with a calmer, fruity and citrusy flavor on the back end.
The impact of terpenes on a particular varietal is determined by how prominently it features in the grape. In some types of wine -- full-on Muscat varieties, in particular -- you’ll see free volatile terpene concentrations reaching 6 milligrams per liter. In semi-Muscat and non-Muscat aromatic varieties, the concentration is lower, generally between one and four milligrams per liter. Some wines have no measurable terpenic properties, and (in addition to having a duller nose), these wines have zero milligrams per liter and often don’t have the herbal air to them that muscat wines do once you’ve allowed the wine to breathe a bit.
How do terpenes impact a bottle of wine?
When the wine you’re drinking is laden with terpenes, the main thing you’ll notice is the pungent aroma present -- both when you first uncork the bottle and as you swish the wine around in the glass after pouring.
Beyond their pleasant smells, terpenes are known for their positive effects on everything from anti-inflammatory properties to ease in falling asleep. You’d have to drink quite a bit of wine to notice these benefits in the short term (with the exception of the whole sleeping thing, perhaps), but feel free to use the terpene-powered perks of wine to justify your stance on that whole “a glass of wine is good for you” argument that pops up in the media every now and then.
In the interim, enjoy the nose on your favorite bottle of wine. The aromas of the terpenes in a particular bottle are most noticeable before they begin to oxidize. Oxidation reduces the pungent aroma of the terpenes and in turn cuts back on the distinct nose of a bottle that makes it unique from other, similar types of wine.
Now that you understand how terpenes impact the aroma of wine, it might be time to start planning your next dinner party. You’ll really impress your friends as you describe the terpenes in wine and the terpenic properties of the bottle on offer. The next time your guest brings over a 1967 Chateau d’Yquem (as any good guest should) and you’re enjoying the aromatic notes of flowers, tropical fruits, butterscotch, vanilla, caramel and oranges, you’ll be able to launch forth with your newly acquired terpene knowledge. Sip, smell, and enjoy.