Beginner’s Guide to Fragrance Structure: Notes, Accords, and How Scents Evolve Over Time

I work with fragrance every day. Still, I find that even experienced buyers sometimes misread a fragrance brief — or make sourcing decisions based on first impressions that don’t hold up in the final application.

The reason is almost always the same. They don’t have a clear mental model of how a fragrance is structured. They don’t understand notes, accords, or how a scent changes over time.

This guide fixes that.

Whether you are sourcing fragrance oils for a personal care line, developing a home fragrance collection, or trying to speak the same language as your perfumers and suppliers — this article gives you the foundation you need.

What Exactly Is a Fragrance Note — and Is It the Same as an Ingredient?

This is the most common point of confusion I see in B2B fragrance sourcing conversations. A fragrance note is not the same as a raw ingredient.

The word "note" has two distinct meanings in perfumery. First, it describes a perceivable aromatic character — the impression your nose registers at a given moment. Second, it describes timing — when within the fragrance’s lifecycle that character is most detectable.

This matters practically. When a fragrance oil specification sheet lists "bergamot" as a top note, it does not necessarily mean the formula contains bergamot essential oil. It may contain a synthetic bergamot-type molecule that creates the same impression. Notes give you a language to describe and predict olfactory character. They are not a formula declaration.

For B2B buyers evaluating fragrance oil samples, this distinction is critical. The note descriptor describes olfactory profile, not raw material composition. If you need to verify actual ingredient content for compliance or allergen labeling purposes, you need a full GC-MS report¹ or an IFRA conformity certificate² — not just the note pyramid.

Quick Reference: Notes vs. Accords vs. Ingredients

Term	What It Means	Practical Example
Note	An aromatic impression perceived at a specific stage of wear	"Bergamot top note" = fresh, citrusy opening character
Accord	A blend of multiple materials creating one unified scent identity	"Rose accord" = a synthetic construction that evokes rose
Raw Ingredient	The actual material inside the formula	Linalyl acetate, Iso E Super, rose absolute

How Does the Fragrance Pyramid Work — and Why Does a Scent Smell Different After 20 Minutes?

The fragrance pyramid is the most important structural model in perfumery. It explains why a scent opens one way on the wrist and smells completely different an hour later.

The model works because different aromatic molecules have different molecular weights. Lighter molecules evaporate first. Heavier ones linger. This creates a scent journey that unfolds in three stages.

The Three Tiers of the Fragrance Pyramid

Top Notes (Head Notes)

Top notes are the first impression. They contain small, light molecules that evaporate quickly. According to the NCBI’s peer-reviewed reference on perfume neuroscience, top notes consist of small, light molecules that evaporate quickly³ and form a person’s initial impression of a fragrance. Most top notes last 5 to 30 minutes on skin.

Common top notes include bergamot, lemon, grapefruit, pink pepper, mint, and light green herbs. These are the notes you smell at the fragrance counter. This is why a fragrance can smell appealing in-store and feel completely different after 30 minutes of wear.

For B2B fragrance oil buyers, this has a direct implication. When you evaluate a sample by smelling the bottle cap or a paper strip, you are detecting primarily the top note character. The heart and base — which define the long-term user experience — require time on skin to properly evaluate. Never make a sourcing decision based on a paper strip alone.

Heart Notes (Middle Notes)

Heart notes emerge as top notes fade. They typically appear 10 to 30 minutes after application and last 2 to 4 hours. They are considered the personality of the fragrance. Most commercial blends concentrate the majority of their olfactory character in this tier.

Common heart notes include jasmine, rose, ylang-ylang, geranium, neroli, cinnamon, cardamom, and nutmeg. These notes are usually more complex and full-bodied than the top tier. They also serve a functional role: they help bridge the transition from the opening impression to the base, softening the sometimes harsh raw character of heavier base note materials.

Base Notes (Soul Notes / Dry Down)

Base notes are the foundation. They are large, heavy molecules that evaporate slowly. NCBI’s perfume chemistry reference confirms that base notes are usually not perceived until 30 minutes after application, and some remain detectable for 24 hours or more. On fabric, certain base notes — particularly musks and ambers — can last several days.

Common base notes include sandalwood, cedarwood, vanilla, amber, musk, patchouli, oud, and vetiver. These materials anchor the blend, extend longevity, and define the lasting impression a product leaves on the user.

The fragrance pyramid was formalized by Jean Carles, a French perfumer who developed this olfactive architecture⁴ into a systematic teaching framework. It remains the dominant structural model in global commercial perfumery today.

Fragrance Note Tier Reference Table

Note Tier	Duration on Skin	Molecular Volatility	Role in Blend	Common Examples
Top Notes	5–30 minutes	High — evaporates fastest	First impression, opening hook	Bergamot, lemon, pink pepper, mint
Heart Notes	20 min – 4 hours	Medium	Personality and character of the fragrance	Jasmine, rose, cinnamon, neroli
Base Notes	4–24+ hours	Low — evaporates slowest	Longevity, depth, dry-down signature	Sandalwood, vanilla, musk, oud

Sources: NCBI Bookshelf (Neurobiology of Sensation and Reward); Eisenberg Paris Olfactory Pyramid Guide; Jean Carles fragrance pyramid methodology

A note on blend percentages: Some consumer guides list fixed percentage ratios per tier (e.g., "top notes = 20% of the formula"). These figures come from DIY blending contexts and do not reflect commercial perfumery practice. In professional fragrance formulation, tier proportions vary widely depending on the materials used, the application type, and the desired performance profile. What matters in commercial formulation is volatility management — not fixed percentage rules.

What Is a Fragrance Accord — and How Is It Different from a Single Note?

This is the concept I see most misunderstood in fragrance sourcing and product development conversations. Most beginner guides use "note" and "accord" interchangeably. They are not the same thing.

A note is a single aromatic character. Think of it as one instrument playing one sound.

An accord is a composite. It is a harmonious blend of multiple raw materials that creates a new, unified olfactory identity. The result goes beyond any single ingredient. Think of it as a chord in music — several notes played together create a feeling that no single note could produce alone.

An accord is built to smell like one thing even though it is made of many. A "suede accord" contains no suede. A "leather accord" contains no leather. Both are constructed from resins, smoky materials, musks, and specific aroma chemicals engineered to evoke those sensory experiences.

How Accords Work in Commercial Fragrance Formulation

When a perfumer creates a fragrance, they typically build the accord first. The accord defines the fragrance’s identity. Other facets — including top note volatiles and performance modifiers — are added around it.

An accord can appear in any tier of the pyramid. A fragrance might open with a sparkling mineral-citrus accord, evolve into a suede-musk accord in the heart, and settle into a warm cashmere-musk accord in the base. Each accord has its own internal volatility profile, which determines when it becomes most prominent during the scent journey.

Here is what this means for B2B buyers. When you purchase a "fresh linen accord," a "sandalwood amber accord," or a "white floral accord" from a fragrance oil supplier, you are purchasing a pre-built composite — not a raw material. Its behavior in your finished product depends on three things:

1. The volatility profile of its component molecules
2. The usage concentration in your formula
3. The product matrix it is applied to — candle wax, lotion base, rinse-off shampoo, and dry hair care all behave differently

What to Ask Your Supplier About Any Accord

Question	Why It Matters
Is this accord IFRA-certified for my product category?	Usage limits differ between leave-on, rinse-off, and home fragrance applications
What is the flashpoint?	Critical for candle and diffuser applications — affects safety classification
Has this been stability-tested in [your base]?	Accords can discolor, separate, or morph in certain emulsified or high-heat systems
Is this batch-to-batch consistent?	Synthetic-dominant accords offer more consistency than natural-only blends
Can you provide a GC-MS report?	Needed for allergen disclosure and regulatory labeling in EU and other markets

Does Every Fragrance Follow the Same Pyramid Structure?

No. This is where most beginner guides fall short. The three-tier pyramid is the dominant model in Western commercial perfumery. It is not universal.

Understanding the alternative structures is directly useful when you are evaluating fragrance oils for specific product types.

Beyond the Classic Pyramid — Four Structural Types

1. Classic Pyramid Structure

The most common in fine fragrance and premium personal care. A fragrance opens with volatile top notes, develops through a heart, and settles into a persistent base. It creates an evolving, layered experience that unfolds over hours.

2. Linear Fragrances

Linear fragrances smell consistent from first application to dry down. There is no meaningful evolution. Many modern functional fragrance products — candles, room sprays, fabric care, air fresheners — are intentionally designed as linear. Consistency throughout the product’s use life is the priority, not a layered olfactory journey.

This is a point that most consumer fragrance guides miss entirely. If you are developing a candle or a diffuser oil, specifying a pyramid-structured fragrance oil can create problems. The top note character that makes a fragrance smell great on first cold-throw may be entirely different from the scent delivered during a full burn cycle. A linear fragrance oil offers more predictable, consistent performance across the full product experience.

3. Soliflore Structure

Built around one dominant botanical character. Supporting materials play a structural and longevity role only. Rose, jasmine, and tuberose soliflores are classic examples. Common in premium personal care and fine fragrance applications where a single, clear olfactory identity is the product promise.

4. Inverted / Base-Forward Structure

Some perfumers — particularly those working within Middle Eastern attar and oud traditions — lead with heavy base-note materials that slowly lift to reveal fresher facets. Oud, resins, and amber open the composition. Fresher notes emerge over time rather than fading away.

This structure is gaining relevance for Western brands targeting Middle Eastern export markets or developing oud-based product lines. Understanding this inverted approach helps you specify the right raw materials and evaluate whether a fragrance oil behaves appropriately for your target consumer experience.

How Does Fragrance Concentration Affect Note Development?

Fragrance concentration is deeply linked to how notes evolve. This connection is almost never covered in beginner fragrance guides, even though it directly affects product performance decisions.

Concentration refers to the percentage of pure fragrance oil blended with alcohol and water. Higher oil content produces a richer, longer-lasting scent. More importantly for this discussion, it changes which note tier dominates the experience and how quickly the evolution unfolds.

The Concentration Spectrum and Note Behavior

Higher-concentration formats (EDP, Extrait de Parfum) develop gradually. The fragrance moves through a clear top-to-heart-to-base journey. The base accord gets significant expression time. Lower-concentration formats (EDT, EDC) reveal their full character almost immediately. The journey is compressed. Top notes dominate the opening experience more strongly.

This is not just a longevity difference. It is a structural and character difference. The same core accord can feel like a different fragrance entirely depending on concentration format. In general fragrance formulation practice, the EDT version of a fragrance emphasizes bright, projecting top note character. The EDP version of the same accord brings forward the heart and base, creating a warmer, more intimate experience.

For B2B product developers, concentration decisions belong in the brief stage — not after the fragrance oil has been selected. The usage rate of your fragrance oil in your final formula directly determines which tier of the accord will be most prominent in the end user’s experience.

Fragrance Concentration Reference Table

Concentration Type	Fragrance Oil %	Typical Longevity	Note Behavior	Best Suited For
Eau Fraîche	1–3%	1–2 hours	Top note dominant, fast fade	Body mists, post-gym sprays
Eau de Cologne (EDC)	2–6%	2–3 hours	Top-heavy, fast dry-down	Summer wear, light daily-use products
Eau de Toilette (EDT)	5–15%	3–4 hours	Immediate projection, semi-linear	Everyday personal care, light sprays
Eau de Parfum (EDP)	15–20%	4–6 hours	Gradual heart-to-base evolution	Premium personal care, fine fragrance
Extrait de Parfum	20–40%	6–24+ hours	Base-forward, close-to-skin, intimate	Luxury perfumery, concentrated oils

Sources: Twisted Lily Fragrance Concentration Guide; YSL Beauty; Ningen Perfumery; Data Bridge Market Research (EDP segment data)

One useful market context point: EDP formats held 39.2% of the global perfume category by revenue in 2024⁵, making them the single largest concentration segment. This reflects growing consumer preference for longer-lasting, base-forward fragrance experiences. For B2B brands developing premium positioning, EDP-range usage rates deserve serious consideration in the brief.

What Are the Major Fragrance Families — and How Do They Relate to Accord Structures?

Fragrance families group compositions by their dominant olfactory character. They describe the signature accord around which the fragrance is built. Understanding families helps you communicate with suppliers and evaluate whether a fragrance oil matches your product brief.

The Seven Core Fragrance Families

Floral

The largest and most commercially significant category globally. Built around single-flower soliflores or multi-flower bouquets. Jasmine, rose, and ylang-ylang are the most important commercial heart note materials. Floral accords are among the most technically complex to engineer synthetically because a natural rose absolute, for example, contains over 300 identified chemical compounds.

Oriental / Amber

Warm, resinous, and base-forward compositions. Amber, vanilla, benzoin, and labdanum are structural pillars. These fragrances evolve slowly. Base notes dominate throughout. They deliver long sillage and deep dry-down character. Common in premium candles, personal care, and home fragrance applications.

Woody

Sandalwood, cedar, vetiver, and oud anchor this family. Woody accords are used as base structures in virtually every other fragrance family — they provide depth, longevity, and smooth transitions between note tiers. Global demand for oud has grown significantly across Middle Eastern, European, and Asian markets in recent years.

Chypre

Built on the classic oakmoss–labdanum–bergamot accord, first formalized by François Coty in 1917. Post-IFRA restrictions on oakmoss have significantly reformulated this family. Modern chypres substitute synthetic moss molecules and materials like Iso E Super. If you are sourcing for a chypre-family product, current IFRA compliance documentation from your supplier is non-negotiable.

Fougère

A lavender–oakmoss–coumarin accord first constructed in Fougère Royale by Houbigant in 1882. It created an interplay between sweet and bitter with a woody, damp, and cool character — establishing fougères as the foundation of masculine fragrance structure. Modern fougères remain one of the most commercially populated masculine personal care fragrance categories globally.

Fresh / Aquatic

A modern family built almost entirely on synthetic molecules. Calone and related ozonic compounds create oceanic freshness, typically in top and heart positions. This family would not exist without synthetic chemistry. It is popular in mass-market personal care, deodorant, and functional home fragrance applications.

Gourmand

A subdivision of the Oriental family that emerged as a standalone category in the 1990s and 2000s. Built on vanilla, caramel, chocolate, and food-reminiscent accord structures. Strongly driven by younger consumer preferences — teen boys increased their spending on fragrances by 26%⁶ compared to the prior year in 2024, and gourmand accords feature prominently in this demographic’s preferred fragrance profile.

Fragrance Family Reference Table

Family	Signature Accord	Dominant Pyramid Position	Key Product Applications
Floral	Rose / Jasmine Bouquet	Heart	Personal care, fine fragrance, body care
Oriental / Amber	Amber–Vanilla–Resin	Base	Luxury candles, premium personal care
Woody	Sandalwood–Cedar–Vetiver	Base	Universal base support across all categories
Chypre	Oakmoss–Labdanum–Bergamot	All tiers	Premium fragrance (IFRA-reformulated)
Fougère	Lavender–Coumarin–Oakmoss	Heart-Base	Masculine personal care, grooming
Fresh / Aquatic	Ozone–Marine–Calone	Top-Heart	Mass personal care, home care, deodorant
Gourmand	Vanilla–Caramel–Chocolate	Base-Sweet	Consumer personal care, body lotion, candles

How Does Skin Chemistry Affect Fragrance Evolution?

The same fragrance oil does not perform identically on every person. Skin pH, natural sebum levels, body temperature, and hydration all influence how aromatic molecules interact with the skin.

Skin pH typically ranges between 4.7 and 5.75 (NCBI reference data). More acidic skin can enhance or suppress musks and florals. Higher body temperature accelerates volatility and pushes heart notes forward faster. Dry skin absorbs more of the fragrance oil without projecting it, shortening perceived longevity. Oily skin holds fragrance longer.

For product developers and QC teams, this has a direct testing implication. A fragrance oil that performs well on two or three lab testers may behave differently across a broader consumer demographic. Best practice is to test fragrance oil performance across at least five to eight panelists representing different skin types before confirming a final brief. Panelist diversity — skin pH range, age, body temperature variation — produces a more reliable performance read than a small homogeneous group.

On fabric and hair, performance is different again. Base notes tend to be significantly more persistent on textile surfaces. Musk-forward and amber-based accords can remain detectable on fabric for several days. This is directly relevant for home textile fragrance, fabric softener, and scented apparel applications — in these contexts, base note performance is often more commercially important than the top note opening.

What Role Do Synthetic Materials Play in Modern Fragrance Structure?

This is almost entirely absent from consumer-facing guides, yet it is essential knowledge for anyone working in the fragrance supply chain.

The majority of modern fragrances — including many premium and niche perfumes — rely heavily on aroma chemicals. These synthetics are not a compromise. They are often the enabling technology for entire fragrance categories.

The "fresh aquatic" genre would not exist without Calone, a synthetic oceanic molecule first used commercially in the 1990s. White musks in personal care are synthetic replacements for animal-derived musk — safer, consistent, and IFRA-compliant. Iso E Super, a synthetic cedarwood-type molecule, is a structural workhorse used in large quantities as a base note amplifier and sillage modifier.

Regulatory pressure is also reshaping synthetic ingredient use. Brands are phasing out specific synthetic musks, phthalates, and regulated allergens in line with IFRA’s 51st Amendment, effective 2024⁷. Suppliers are responding with new sustainable synthetic materials — including sandalwood substitutes and berry accord innovations — that maintain performance while reducing restricted-substance risk.

For B2B buyers, the practical takeaway is this. When evaluating a fragrance oil supplier, request IFRA compliance certification that is specific to your product application category⁸. IFRA usage limits are not universal — they differ between leave-on skin products, rinse-off products, and non-skin home fragrance applications. The same material may be fully compliant in a candle and restricted in a leave-on lotion. A supplier who cannot provide current, category-specific IFRA conformity certificates is a regulatory and supply chain risk.

Conclusion: Fragrance Structure as a Sourcing Tool

Understanding fragrance structure — notes, accords, pyramid behavior, concentration, and family classification — is not theoretical knowledge. It is a practical sourcing and product development tool.

It helps you evaluate samples more accurately. It helps you write better briefs. It helps you ask better questions of suppliers. It helps your quality team set the right performance benchmarks.

Four things are worth keeping at the top of your mind:

Notes describe timing, not ingredients. The note pyramid tells you what to expect during wear. It does not tell you what is in the bottle. Always request GC-MS data and IFRA certification separately.

The pyramid is a model, not a rule. Candles, diffusers, and functional home fragrance products typically need linear accord structures — not evolving pyramids. Match structure type to product use case before you brief a supplier.

Concentration changes character. The same accord behaves differently at EDT versus EDP usage rates. Concentration decisions belong in the brief, not after formulation.

Compliance is built into structure. IFRA restrictions directly shape which materials are available for which note positions in which product categories. Compliance-first sourcing is not an extra step — it is part of designing a functional fragrance from the beginning.

At PhytoEx, we support buyers at every stage of this process — from raw material sourcing and accord development through stability testing, application testing, and full IFRA compliance documentation. If you are ready to build your next fragrance brief on a foundation that performs across the full product lifecycle, contact our team to request samples and formulation support.

---