Where Wine Flavors Come From: The Science of Wine Aromas

Written by Madeline Puckette

Why does wine taste the way it does? If you love wine, you’ve no doubt read countless wine tasting descriptions like this one:

“blueberry aromas and accents of camphor, anise and the slightest floral hint…”

Wine Advocate 2010 Penfold’s “Grange” Shiraz

You might also be wondering: are winemakers blending blueberries into their wine? The answer is no. The secret lies in aroma compounds.

The Origin of Wine Flavor

From vanilla and apple to soil and chalk, wine flavors can be organized into 3 primary groups: Fruit/Floral/Herbal, Spice, and Earth.

Special thanks to Master Somms’ Geoff Kruth and Matt Stamp, who organized the aroma compounds in this guide. You can listen to their free podcast and learn how to apply this to blind tasting.

Fruit/Floral/Herbal Flavors

wine-flavors-esters

Esters: Fruit & Flowers

Wine esters come from acids. Esters are used extensively in the flavor industry for everything from essential oils to candy. In wine, esters provide the building blocks of fruit flavors.

Apple:
Chardonnay, etc
Raspberry:
Grenache, etc

pyrazine-wine-flavors-bell-pepper

Pyrazines: Herbaceous

Pyrazine is an aromatic organic compound that has vegetable-like smells. It’s also one of the fundamental aroma compounds in chocolate and coffee.

Bell Pepper:
Cabernet Franc & Carménère
Grass:
Sauvignon Blanc

wine-aromas-terpenes

Terpenes: Rose & Lavender

The smell of Christmas trees and desert sage are two classic examples of terpenes. In wine, they can smell anywhere from sweet and floral to resinous and herbaceous. By the way, terpenes are a highly desired trait of hops and beer making.

Lychee:
Gewürztraminer
Rose:
Muscat Blanc
Lavender:
Grenache & Côtes du Rhône
Eucalyptus:
Australian Shiraz

wine-flavors-fruit-thiols

Thiols: Bittersweet Fruit

A thiol is an organosulfur compound that smells fruity in tiny amounts, but in larger amounts, it smells like garlic and is considered a wine fault. Thiols are also a building block of earthiness.

Grapefruit:
Vermentino, Sauvignon Blanc, Colombard
Black Currant:
Red Bordeaux and other Cabernet Sauvignon & Merlot

Earthy Flavors

wine-flavors-sulfur-compounds

Sulfur Compounds: Rocks

Sulfur compounds may be the secret to minerality in wine. Some sulfur compounds smell fantastic, such as the chalk-like aroma in fine Chablis. Some sulfur compounds are bad, like the smell of wet wool, which is a wine fault caused by UV damage.

Chalk:
Chablis & Champagne
Metallic:
Young, Freshly Opened Red Wine

volatile-acidity-wine-flavors

Volatile Acidity: Balsamic & Pickle

Bacteria present in winemaking can cause volatile acidity (a.k.a. acetic acid.) In high doses, volatile acidity smells like acetone, but in low doses, it can add great complexity and is a feature of many very fine wines.

Balsamic:
Chianti & Amarone della Valpolicella
Pickles:
Red Burgundy

wine-flavors-brett

Brettanomyces: Clove & Bacon

Phenols are a group of chemical compounds that are similar to alcohols. Phenols are naturally occurring in many things, including sesame seeds, peppers, and even cannabis. In wine, one type of phenol is when a wild yeast called Brettanomyces can add either a lovely (clove and bacon) aroma or a very detestable (horse) aroma to wine.

Clove:
Châteauneuf-du-Pape & Côtes du Rhône
Bacon:
Paso Robles/Central Coast Syrah, Barossa Valley Shiraz

geosmin-wine-flavors

Geosmin: Earth & Mushroom

Geosmin is an organic compound from a type of bacteria. It might just be the most earthy-smelling compound out there. If you love beets, mushrooms, and the smell of potting soil, then Geosmin is your friend.

Soil & Mushroom:
Common in Old World Wines and some new world wines

Spicy Flavors

rotundone-wine-flavor-aroma

Rotundone: Peppercorn

Rotundone is a kind of terpene that is found in the essential oils of black pepper, marjoram, oregano, rosemary, thyme, and basil. It gives that classic peppery aroma that you’ve probably tasted on great red wines.

Peppercorn:
Syrah, Grüner Veltliner, & Cabernet Sauvignon
Basil:
Dry Riesling
Pink Peppercorn:
Viognier, Gewürztraminer

lactones-wine-flavors-aroma-compounds

Lactones: Vanilla & Coconut

Lactones, and particularly gamma-Lactones are esters found in sweet and creamy smelling foods such as honey wheat bread, peaches, coconut, roasted hazelnut, butter, and even cooked pork!

Vanilla & Coconut:
Oak-aged red & white wine
Hazelnut:
Aged Sparkling Wine

thiols-wine-flavors-aroma-compounds

Thiols: Smoke & Chocolate

Thiols can taste like grapefruit pith and passion fruit, but in higher doses will smell and taste like smoky, skunk, tar, and chocolate.

Coffee:
Sonoma Pinot Noir
Chocolate:
Argentine Malbec

wine-flavors-noble-rot

Botrytis: Honey & Ginger

Botrytis Cinerea or ‘Noble Rot’ is a type of fungus that eats ripe fruits and vegetables. You’ve probably seen it before on a box of rotten strawberries! Despite its negative connotation with fresh fruits, it adds richness and a milieu of amazing aromas to dessert wines. There are a few compounds associated with Botrytis that you may have tasted:

  • Sotolon: Honey, Fenugreek, Curry
  • Furaneol: Caramel, Pineapple, Strawberry
  • Phenylacetaldehyde: Rose, Cinnamon, Ginger
Marmalade:
Sauternes, Tokaji
Ginger:
Spätlese Riesling

how to taste wine step 2 illustration of woman smelling a glass of wine

Tasting Wine Smarter

Next time you taste wine, think about how the flavor may be one or a combination of the fundamental wine flavors above. If you’d like to know how to pick out flavors better, check out this useful guide on tasting wine.

Sources

  • Pyrazines in food, organoleptic properties
  • Contribution of Volatile Thiols to the Aromas of White Wines
  • Identification of Volatile and Powerful Odorous Thiols in Bordeaux Red Wine Varieties
  • all about gamma-Lactones
  • Changes in Wine Aroma Composition According to Botrytized Berry Percentage

Written byMadeline Puckette

James Beard Award-winning author and Wine Communicator of the Year. I co-founded Wine Folly to help people learn about wine. @WineFolly