Beyond the Grape: Exploring Secondary Aromas in Wine

The Scent of Transformation

Once you’ve explored a wine’s primary aromas, the direct voice of grape variety and terroir, you’re ready to move deeper into its aromatic identity. This is where secondary aromas come into focus. These are the sensory fingerprints of fermentation and winemaking, and they bring a whole new layer of complexity to the glass.

From creamy butter to freshly baked brioche, these aromas do not originate in the vineyard. Instead, they arise in the cellar, shaped by yeast, bacteria, vessels, and temperature. Understanding secondary aromas allows you to interpret the winemaker’s intention and the stylistic choices that define the wine.

Secondary aromas reflect both microbial activity and human craftsmanship. They are the result of transformation, both scientific and artistic.

What Are Secondary Aromas?

Secondary aromas are produced during alcoholic and malolactic fermentation. They may also emerge during early winemaking techniques such as lees contact or bâtonnage (stirring of the lees).

Whereas primary aromas come from the grape, secondary aromas are shaped by:

• Yeast activity
• Malolactic bacteria
• Fermentation temperature
• Fermentation vessel (such as stainless steel, oak, or amphora)
• Contact with lees (spent yeast cells)

They are more technical than terroir-driven. Still, they are essential in shaping the wine’s personality, especially in its youth.

Key Secondary Aroma Families - (Le Nez du Vin)

Yeasty & Doughy Aromas

• Aromas: Bread dough, biscuit, brioche, toast
• Cause: Yeast autolysis and lees aging
• Typical in: Champagne, Crémant, Cava, and other traditional method sparkling wines

When a wine rests on its lees, yeast cells gradually break down and release compounds that produce these bakery-like aromas. They are particularly prominent in fine sparkling wines or lees-aged still wines.

Lactic Aromas

• Aromas: Butter, cream, yogurt, sour cream
• Cause: Malolactic fermentation (MLF), which converts sharp malic acid into softer lactic acid
• Typical in: Barrel-aged Chardonnay, Chenin Blanc, and many red wines

Malolactic fermentation is often used to round out acidity and add a creamy texture. However, some winemakers choose to block it to retain freshness.

Estery & Fermentation Aromas

• Aromas: Banana, pear drop, bubblegum, candy
• Cause: Fast or cool fermentations with certain yeast strains, or carbonic maceration
• Typical in: Beaujolais Nouveau, young Gamay, and some aromatic whites

These bright and fruity aromas are often associated with youth and tend to fade within the first year. They are common in wines designed for early consumption.

Savory, Sulfide, or Reductive Notes

• Aromas: Sourdough, cheese rind, struck match, flint, subtle sulfur
• Cause: Reductive winemaking and extended lees contact
• Typical in: Muscadet Sur Lie, reductively styled Chardonnay, and some natural wines

In controlled amounts, these aromas add depth and complexity. In excess, however, they can overpower or detract from the wine’s balance.

Comparing Secondary Aromas in Red vs White Wines

How Secondary Aromas Help You Understand a Wine

These aromas reveal valuable information about the wine's production process.

Fermentation Style

Cool, slow fermentations tend to highlight esters and fruitiness.
Warmer fermentations may reduce esters but enhance texture and complexity.
Carbonic maceration produces instantly recognizable fruity aromas, often with low tannins and bright acidity.

Yeast and Bacteria Activity

Inoculated fermentations with selected yeast strains tend to be clean and consistent.
Wild fermentations introduce complexity and variation.
Malolactic fermentation softens acidity and adds lactic tones.

Vessel Choice

Stainless steel preserves freshness and emphasizes fruit.
Oak introduces oxidative notes and integrates lactic and toasty aromas.
Amphorae and concrete allow micro-oxygenation without imparting wood flavours.

Fermentation Types and Their Aromatic Influence

Spontaneous Fermentation

This type uses ambient yeast from the vineyard or winery. It can produce nuanced aromas but may result in less predictable outcomes.

Inoculated Fermentation

Using cultured yeasts offers control and consistency. Specific strains are chosen to highlight esters, suppress unwanted microbes, or control the speed of fermentation.

Malolactic Fermentation

This bacterial process transforms sharper malic acid into lactic acid. It is common in nearly all red wines and in many full-bodied whites.

How Secondary Aromas Evolve

Secondary aromas are typically short-lived. They fade or transform over time, especially in bottle-aged wines.

• Estery notes such as banana or bubblegum tend to disappear within the first 12 to 18 months.
• Yeasty aromas may evolve into nutty or oxidative tones.
• Lactic notes become better integrated and may fade beneath more mature tertiary characters.
• Sulfide-related aromas may intensify, mellow, or vanish depending on oxygen exposure and closure type.

As these aromas recede, they are often replaced by tertiary aromas, which emerge from oxidation and long-term aging.

Wines That Showcase Secondary Aromas

Champagne (Traditional Method)

• Aromas: Toast, biscuit, brioche
• Method: Long aging on lees

California Chardonnay

• Aromas: Butter, cream, yogurt
• Method: Barrel fermentation and full malolactic fermentation

Beaujolais Nouveau

• Aromas: Banana, bubblegum
• Method: Carbonic maceration

Muscadet Sur Lie

• Aromas: Bread crust, salty dough
• Method: Lees aging in stainless steel

White Burgundy (Reductive Style)

• Aromas: Flint, struck match
• Method: Low oxygen exposure and sulfur control

Training Your Nose for Secondary Aromas

1. Use Le Nez du Vin Aroma Kits

Le Nez du Vin includes many secondary aromas, such as butter, brioche, and yogurt. These can train your sensory memory and build recognition.

2. Taste Comparative Styles

Try the same grape fermented in stainless steel versus oak, or with and without malolactic fermentation. These tasting experiments help isolate differences.

3. Note Texture Alongside Aroma

Secondary aromas often come with a change in mouthfeel. Lactic aromas usually signal a smoother, creamier wine. Yeasty wines may have a fuller texture due to lees contact.

4. Smell Raw Ingredients

Smell plain yogurt, brioche, or sourdough dough in the kitchen. Building direct references improves aroma recall in the glass.

Common Misinterpretations

Understanding the context and wine style is essential. Not every butter note is pleasant, and not every sulfide note is desirable.

The Art of Fermentation in Your Glass

Secondary aromas represent the transformation from grape juice into wine. They reflect the silent labor of yeast and bacteria, guided by the hands of the winemaker. These aromas tell you how a wine was made, which path it took in the cellar, and what style the producer intended.

Where primary aromas speak of the vineyard, secondary aromas tell the story of the winery. Learning to recognize and interpret them deepens your understanding of wine and enhances every glass you taste.

In the world of wine appreciation, these are the layers that connect chemistry to craftsmanship, and microbiology to mastery.

About the Author

Sébastien Gavillet is COO of Wine Aromas – Le Nez du Vin. A renowned wine and whisky expert, winemaker, and distiller, Sébastien has been working with Le Nez du Vin for over 25 years. He is the author of Discovering and Mastering Single Malt Scotch Whisky and the International Whisky Guide series. He serves as a panel chair and examiner for The Council of Whiskey Masters, shaping global tasting standards and mentoring the next generation of spirits professionals.