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Essential Oil Notes: A Complete Guide for Skincare and Soapmaking (Pt 1)

20 minute read This is Part One of our Three Part series on Essential Oils.  Comming up in the next few weeks: Part Two: Essential Oil Safety and Dermal Limits - A Beginner's Guide for Skincare Formulators Part Three: Flash Points of Essential Oils: The Science Behind Protecting Your Aroma When you blend essential oils for skincare or soapmaking, have you noticed how some fragrances disappear within hours while others linger for days? Understanding essential oil notes is the key to creating balanced, long-lasting aromatic blends that don't fade too quickly. This guide explores what essential oil notes are, why they matter in formulation, and how to use them to craft beautiful, enduring fragrances in your products. Here’s What You’ll Learn What Are Essential Oil Notes? Why Volatility Matters Why Notes Matter in Skincare and Soapmaking The Three Notes Explained Note Classification Can Overlap Classic Note Ratios for Balanced Blends How to Blend by Notes: Step-by-Step Popular Blend Recipes by Note Special Considerations for Soapmaking Advanced Blending Techniques Troubleshooting Common Problems Storage and Stability Documentation and Record-Keeping Wrap-up What Are Essential Oil Notes? Essential oil notes refer to the classification of oils based on their volatility—how quickly they evaporate and how long their aroma lasts. This concept comes from traditional perfumery, where fragrances are carefully layered to create complex, evolving scents that develop over time. Essential oils are categorised into three main notes: Top Notes (Head Notes): Light, fresh, uplifting aromas that evaporate quickly—typically within 30 minutes to 2 hours. Middle Notes (Heart Notes): Warm, soft, balancing aromas that form the body of your blend—lasting 2 to 4 hours. Base Notes: Deep, rich, grounding aromas that evaporate slowly—lingering for 4 to 8 hours or even days. Think of essential oil notes like musical notes in a symphony. Top notes provide the bright, initial impression; middle notes carry the melody; and base notes offer depth and foundation. Together, they create a harmonious, well-rounded fragrance experience. Why Volatility Matters The concept of notes is directly tied to molecular weight and volatility. Essential oils contain dozens or even hundreds of individual chemical compounds, each with different evaporation rates. Light molecules (like those in citrus oils) evaporate quickly, giving us top notes. Heavy molecules (like those in wood and resin oils) evaporate slowly, creating base notes. Middle notes contain medium-weight molecules that bridge the two. Understanding this chemistry helps you predict how your blends will behave over time and how to compensate for rapid evaporation. Why Notes Matter in Skincare and Soapmaking Fragrance Longevity One of the most common complaints about natural products is that the scent fades too quickly. This happens because many formulators rely heavily on top-note essential oils, particularly citrus without balancing them with middle and base notes. When you understand notes, you can anchor your fast-evaporating oils with slower-evaporating base notes, extending the life of your fragrance from hours to days. This creates a more satisfying sensory experience for your customers. Scent Evolution A well-balanced blend doesn't smell the same from first application to final dry-down. It evolves, revealing different aromatic layers as the hours pass. Initial application highlights the bright top notes perhaps fresh bergamot and lemon. After 30 minutes, the top notes fade and middle notes emerge maybe soft lavender and geranium. Several hours later, the base notes dominate warm sandalwood and patchouli. This aromatic journey creates depth and interest, making your products memorable. Product Type Considerations Different product formats interact with essential oil notes in unique ways: Soap: The saponification process and high pH can alter or diminish certain essential oils. Citrus top notes often fade during cure time or within weeks of use. Using more base notes ensures your soap retains scent throughout its life. Leave-on skincare (creams, lotions, body oils): All three notes can shine because the product remains on skin for hours. Balancing notes creates a pleasant, evolving experience. Rinse-off products (cleansers, shampoos): Top and middle notes have more impact because the product is washed away quickly. Heavy base notes may be less noticeable. Cost Efficiency Base-note essential oils tend to be more expensive than top notes. However, because they're more concentrated and longer-lasting, you often need less of them. Understanding notes helps you create cost-effective blends that deliver maximum aromatic impact. Therapeutic Balance Beyond fragrance, notes also relate to aromatherapeutic properties. Top notes are often energising and uplifting; middle notes are balancing and harmonising; base notes are grounding and calming. Blending across all three notes creates products that support both physical and emotional wellbeing. The Three Notes Explained Top Notes (Head Notes) Characteristics: Light, fresh, bright, sharp, or citrusy aromas Evaporate within 30 minutes to 2 hours Create the first impression Often energising, uplifting, or clarifying Lower molecular weight Common Top-Note Essential Oils: Citrus family: Lemon, lime, bergamot, grapefruit, sweet orange, mandarin, tangerine Mints: Peppermint, spearmint Herbs: Basil, eucalyptus, tea tree Others: Lemongrass, lemon myrtle, citronella Usage Tips: Use top notes at 20–40% of your blend for balanced formulations Increase to 50–60% if you want a bright, fresh-dominant scent In soap, consider using top notes at lower percentages as they fade fastest Pair with base notes to extend longevity Top-Note Challenge in Soap:Citrus oils are notoriously difficult to retain in cold-process soap. The alkaline environment and curing process can strip away these delicate aromas within weeks. Using litsea cubeba (may chang) or lemongrass alongside expressed citrus oils helps anchor the scent. Always increase citrus oil percentages slightly to compensate for loss. Middle Notes (Heart Notes) Characteristics: Soft, warm, floral, herbaceous, or spicy aromas Evaporate within 2 to 4 hours Form the main body and character of your blend Often balancing, harmonising, or soothing Medium molecular weight Common Middle-Note Essential Oils: Florals: Lavender, geranium, chamomile, ylang-ylang, neroli Spices: Black pepper, cardamom, coriander, ginger Herbs: Clary sage, rosemary, marjoram, fennel Others: Pine, cypress, juniper berry, tea tree (overlaps with top) Usage Tips: Use middle notes at 30–50% of your blend as the foundation They act as bridges between volatile top notes and heavy base notes Excellent for creating well-rounded, balanced blends Most middle notes hold up well in both soap and skincare Why Middle Notes Matter:Middle notes are the "heart" of your fragrance. They emerge once top notes fade and work harmoniously with base notes to create a smooth transition. Without middle notes, your blend can feel disjointed—jumping abruptly from bright citrus to heavy wood. Base Notes Characteristics: Deep, rich, earthy, woody, or resinous aromas Evaporate slowly, lasting 4 to 8 hours or longer Provide depth, grounding, and staying power Often calming, centering, or sensual High molecular weight Common Base-Note Essential Oils: Woods: Sandalwood, cedarwood, rosewood Resins: Frankincense, myrrh, benzoin Roots: Vetiver, ginger (can overlap with middle) Others: Patchouli, ylang-ylang (overlaps with middle), vanilla absolute Usage Tips: Use base notes at 10–25% of your blend A little goes a long way, base notes are potent Essential for soap to maintain scent through cure and use Act as fixatives, slowing the evaporation of lighter notes Base Notes as Fixatives:Base notes don't just add their own aroma, they also slow down the evaporation of top and middle notes. This "fixative effect" extends the entire blend's longevity. Patchouli, vetiver, and sandalwood are particularly effective fixatives. Note Classification Can Overlap Some essential oils straddle categories, exhibiting characteristics of two notes: Ylang-ylang: Middle to base (sweet floral with lasting depth) Clary sage: Top to middle (bright opening, herbaceous body) Tea tree: Top to middle (fresh camphoraceous opening, medicinal body) Ginger: Middle to base (spicy warmth with earthy depth) These "bridge oils" are valuable for creating smooth transitions between note categories. Classic Note Ratios for Balanced Blends While there's no single "correct" ratio, these traditional perfumery guidelines create well-balanced blends: Balanced Blend (Classic Pyramid) Top notes: 30% Middle notes: 50% Base notes: 20% This ratio produces a harmonious fragrance that evolves gracefully, with each note getting time to shine. Fresh & Uplifting Blend Top notes: 50% Middle notes: 30% Base notes: 20% Great for morning skincare products, energising body washes, or citrus-forward blends. Deep & Grounding Blend Top notes: 20% Middle notes: 30% Base notes: 50% Perfect for evening skincare, massage oils, or earthy, calming products. Soap-Specific Ratio Top notes: 20% Middle notes: 40% Base notes: 40% Compensates for the loss of volatile top notes during saponification and cure. How to Blend by Notes: Step-by-Step Step 1: Choose Your Direction Decide on the overall aromatic character you want: Fresh and citrusy? Floral and soft? Earthy and grounding? Spicy and warm? This guides your note selection. Step 2: Select Oils from Each Category Choose 1–2 oils from each note category that complement your chosen direction: Example: Fresh Garden Blend Top: Lemon (bright, clean) Middle: Lavender (soft, floral) Base: Cedarwood (woody, grounding) Step 3: Calculate Your Ratios Decide on your note ratio based on product type and desired effect. For a balanced blend, use 30% top, 50% middle, 20% base. If your total essential oil load is 1% of your formula (typical for facial products), and you're making 100g: Total essential oils: 1g Top notes (30%): 0.3g lemon Middle notes (50%): 0.5g lavender Base notes (20%): 0.2g cedarwood Step 4: Create a Test Blend Use drops in a small vial or bottle Apply the same ratios (e.g., 3 drops lemon, 5 drops lavender, 2 drops cedarwood) Let it sit (covered) for 24–48 hours to allow notes to marry Step 5: Evaluate and Adjust Smell your test blend at different intervals: Immediately: Are the top notes too sharp or just right? After 1 hour: Do the middle notes come through beautifully? After 4–8 hours: Are the base notes pleasant and lasting? Adjust ratios as needed. If top notes dominate too much, reduce them. If the blend fades too quickly, increase base notes. Step 6: Test in Product Essential oils behave differently in different bases. Test your blend in your actual product formulation: In soap, scent may fade or morph during cure In oil-based products, scent disperses differently than in water-based products pH and other ingredients can affect aroma Always make a small test batch before committing to full production. Popular Blend Recipes by Note Energising Morning Blend Top (40%): 30% sweet orange, 10% peppermint Middle (40%): 30% rosemary, 10% eucalyptus Base (20%): 20% cedarwood Perfect for shower gels, morning moisturisers, or wake-up body oils. Calming Evening Blend Top (25%): 25% bergamot Middle (50%): 40% lavender, 10% chamomile Base (25%): 15% sandalwood, 10% frankincense Ideal for night creams, pillow mists, or relaxing bath products. Fresh & Floral Blend Top (35%): 25% lemon, 10% grapefruit Middle (45%): 35% geranium, 10% lavender Base (20%): 15% patchouli, 5% vetiver Beautiful for body lotions, hand creams, or facial mists. Earthy & Grounding Blend Top (20%): 20% juniper berry Middle (30%): 20% clary sage, 10% black pepper Base (50%): 30% sandalwood, 20% vetiver Excellent for massage oils, grounding balms, or meditative products. Citrus Grove Soap Blend Top (25%): 15% sweet orange, 10% litsea cubeba Middle (40%): 30% lavender, 10% palmarosa Base (35%): 25% patchouli, 10% benzoin Formulated to retain citrus brightness through cold-process saponification. Special Considerations for Soapmaking Why Soap Is Different Cold-process soapmaking involves high temperatures (during saponification), high pH (alkaline environment), and a long cure time (4-6 weeks). All of these factors can alter or diminish essential oil aromas. What happens to notes in soap: Top notes: Often fade significantly or disappear entirely Middle notes: Usually hold well but may soften Base notes: Remain strong and stable Soap Blending Strategies Strategy 1: Increase Base NotesUse 40–50% base notes instead of the typical 20%. This ensures lasting fragrance throughout the bar's life. Strategy 2: Overpour Top NotesIf you want citrus in your soap, use 30–50% more than you would in skincare. Expect some loss, but enough will remain to provide initial brightness. Strategy 3: Use Anchoring OilsCertain essential oils act as "anchors" in soap, helping other oils stick around: Litsea cubeba (may chang) anchors citrus oils Patchouli and vetiver anchor floral and herbaceous oils Clays and oat flour can also help "hold" scent Strategy 4: Add Oils at TraceAdd your essential oil blend when your soap reaches light to medium trace (not at the beginning with other oils). This minimises exposure to heat and alkali. Strategy 5: Test and WaitAlways test soap blends in small batches and wait through the full cure time before judging scent retention. What smells strong at unmoulding may fade, or what seems faint may strengthen. Advanced Blending Techniques Synergy Blending Some essential oils enhance each other when combined, creating a scent that's more than the sum of its parts. Look for oils within the same aromatic family (e.g., citrus + citrus) or complementary families (e.g., floral + woody). Natural pairs: Lavender + rosemary (herbaceous harmony) Bergamot + geranium (bright floral) Sandalwood + rose (soft, sensual) Peppermint + eucalyptus (cooling clarity) Accord Building An accord is a small blend of 2–3 oils that smell like a single note. Create accords first, then combine them into your final blend. Example: Green Accord Clary sage + pine + juniper berry = fresh forest scent Use this "Green Accord" as your middle note, then add citrus top notes and cedarwood base notes. The Rule of Three Start simple: use just three essential oils, one from each note category. Master three-oil blends before expanding to complex five- or seven-oil formulations. Three oils can create stunning, sophisticated fragrances without overwhelming complexity. Troubleshooting Common Problems "My blend smells great in the bottle but disappears on skin"Solution: Increase base notes. Your blend is likely top-note heavy. Add 5–10% more base-note oils to anchor the fragrance. "My soap loses all scent after curing"Solution: Use soap-specific ratios with higher base notes (40–50%). Consider clays to hold scent and add oils at light trace. "All my blends smell the same"Solution: Experiment outside your comfort zone. If you always use lavender, try geranium or ylang-ylang instead. Swap cedarwood for vetiver. Small changes create big differences. "My blend smells too heavy or cloying"Solution: Increase top notes for brightness and lift. Add 10–15% of total % of citrus or mint to lighten deep, resinous blends. "My citrus soaps fade within a month"Solution: Replace expressed citrus oils with distilled versions where possible (they have less furanocoumarins but better staying power). Use litsea cubeba as an anchor. Increase usage rates by 30–50%. Storage and Stability Essential oil blends evolve over time, especially when exposed to heat, light, and oxygen. To maintain aromatic integrity: Store blends in dark glass bottles (amber or cobalt blue) Keep in cool, dark places (not bathroom cabinets or sunny shelves) Fill bottles fully to minimise oxygen exposure Label with date and replace oxidation-prone oils (citrus, tea tree, pine) after 12 months Base-note-dominant blends improve with age as notes marry and mellow. Top-note-heavy blends should be used within 6 months for maximum freshness. Documentation and Record-Keeping Keep detailed records of every blend you create: Date created Note ratios (e.g., 30/50/20) Exact oil percentages and weights Product type (soap, lotion, balm) Scent impressions at initial blending, after 24 hours, after one week Customer feedback This documentation helps you replicate successful blends and refine unsuccessful ones. Over time, you'll develop your signature blending style. Understanding essential oil notes transforms your formulation work from guesswork to intentional artistry. By balancing top, middle, and base notes, you create products with lasting, evolving fragrances that delight your customers and set your brand apart. Start with simple three-oil blends using the classic 30/50/20 ratio. Smell your blends at different intervals to understand how they develop. Adjust for product type especially soap, where base notes are your best friend. With practice, you'll develop an intuitive sense for how notes work together, creating sophisticated, long-lasting blends that showcase the full aromatic beauty of essential oils. Whether you're crafting a bright morning face wash or a grounding evening body oil, notes are your roadmap to fragrance success. Ready to start blending? Choose one oil from each note category, create a small test blend, and observe how it evolves over the next 8 hours. That hands-on experience will teach you more than any theory alone. Happy crafting! Top notes (bright, volatile, fastest to fade) Basil (Ocimum basilicum) Bergamot (Citrus bergamia) Bergamot Mint (Mentha citrata) Camphor (Cinnamomum camphora) Clementine (Citrus clementina) Eucalyptus globulus (Eucalyptus globulus) Eucalyptus radiata (Eucalyptus radiata) Eucalyptus lemon/citriodora (Corymbia/Eucalyptus citriodora) Fir Needle (fresh fractions; Abies spp.) Galbanum (fresh green lift; Ferula galbaniflua) Grapefruit (Citrus paradisi) Juniper Berry (Juniperus communis) Lemon (Citrus limon) Lemongrass (Cymbopogon citratus) Lime (Citrus aurantifolia) Mandarin (Citrus reticulata) Neroli (Citrus aurantium flower) Orange, Bitter (Citrus aurantium) Orange, Sweet (Citrus sinensis) Peppermint (Mentha × piperita) Petitgrain (Citrus aurantium leaf/twig) Pine (Pinus spp.) Ravensara (Ravensara aromatica) Rosemary (Rosmarinus officinalis; fresher CTs) Sage, Dalmatian (Salvia officinalis; can bridge) Spearmint (Mentha spicata) Tagetes (Tagetes minuta) Tangerine (Citrus reticulata) Tea Tree (Melaleuca alternifolia; can bridge) Verbena, Lemon (Aloysia citriodora) Yuzu (Citrus junos) Top–Middle (bridge between sparkle and heart) Basil (light chemotypes) Bergamot Mint (Mentha citrata) Camphor (fresh camphoraceous) Eucalyptus globulus / radiata Eucalyptus lemon (citriodora) Fir Needle (many lots) Galbanum (green terpene into earthy heart) Juniper Berry Lavender (Lavandula angustifolia) Lavandin (Lavandula × intermedia) Lemongrass (citral-rich) Litsea cubeba / May Chang (Litsea cubeba) Melissa / Lemon Balm (Melissa officinalis) Neroli (Citrus aurantium flower) Petitgrain Pine (brighter fractions) Rosemary (many chemotypes) Sage, Dalmatian Tea Tree (Melaleuca alternifolia) Middle notes (heart of the blend; florals, herbs, soft spice) Angelica (Angelica archangelica; seed/root—often shades deeper) Anise / Aniseed (Illicium verum / Pimpinella anisum) Bay, West Indian (Pimenta racemosa) Black Pepper (Piper nigrum) Cardamom (Elettaria cardamomum) Carrot Seed (Daucus carota) Chamomile, German (Matricaria recutita) Chamomile, Roman (Chamaemelum nobile) Cinnamon Leaf (Cinnamomum verum; bark leans deeper) Citronella (Cymbopogon nardus) Clary Sage (Salvia sclarea) Clove (Syzygium aromaticum; bud/leaf—deeper edges) Coriander seed (Coriandrum sativum) Cumin (Cuminum cyminum) Cypress (Cupressus sempervirens) Dill (Anethum graveolens) Elemi (Canarium luzonicum; lemony resin) Fennel, sweet (Foeniculum vulgare) Geranium / Rose Geranium / Bourbon (Pelargonium spp.) Ginger (Zingiber officinale) Helichrysum / Immortelle (Helichrysum italicum) Ho Wood (Cinnamomum camphora linalool CT) Honeysuckle (absolute/extract) Hyssop (Hyssopus officinalis) Jasmine absolute (Jasminum officinale / grandiflorum) Kanuka (Kunzea ericoides) Lavender (core heart presence) Lavandin (heartier lavender hybrid) Linden Blossom (Tilia spp. absolute) Manuka (Leptospermum scoparium) Marjoram, sweet (Origanum majorana) May Chang / Litsea (Litsea cubeba) Melissa / Lemon Balm (Melissa officinalis) Myrtle (Myrtus communis) Neroli (headspace lifts; heart persists) Niaouli (Melaleuca quinquenervia) Nutmeg (Myristica fragrans) Palmarosa (Cymbopogon martinii) Parsley (leaf/seed; Petroselinum crispum) Roman Chamomile (Chamaemelum nobile) Rose (Rosa damascena / R. centifolia) Rosewood (Aniba rosaeodora) Rosemary (many CTs sit here) Sage (Spanish—Salvia lavandulifolia) Spruce (Picea spp.) Tuberose absolute (Polianthes tuberosa) Turmeric (Curcuma longa) Violet Leaf (Viola odorata) Yarrow (Achillea millefolium) Middle–Base (hearty with persistence; soft fixatives) Angelica (root/seed; Angelica archangelica) Cajeput (Melaleuca cajuputi) Cinnamon (bark/leaf; spicy heart with depth) Clove (bud/leaf) Elemi (resin bridge that lingers) Frankincense Serrata / Frankincense Olibanum Ginger (Zingiber officinale) Helichrysum / Immortelle (Helichrysum italicum) Myrrh (Commiphora myrrha) Oakmoss absolute (Evernia prunastri) Palmarosa (Cymbopogon martinii) Patchouli (Pogostemon cablin) Rose (particularly heavier absolutes) Rosewood (Aniba rosaeodora) Sandalwood (Santalum album / spp.) Spikenard (Nardostachys jatamansi) Vetiver (Chrysopogon/Vetiveria zizanoides) Ylang Ylang (Cananga odorata, complete or heavier fractions) Base notes (slowest to evaporate; deep fixatives) Agarwood / Oud (Aquilaria spp.; often sold as absolute/CO2) Amyris (Amyris balsamifera) Angelica Root (Angelica archangelica) Balsam, Peru (Myroxylon balsamum; absolute) Benzoin resinoid (Styrax benzoin) Cedarwood (Atlas, Virginian, Himalayan) Frankincense Serrata / Frankincense Olibanum Labdanum / Cistus (Cistus ladanifer) Myrrh (Commiphora myrrha) Oakmoss absolute (Evernia prunastri) Patchouli (Pogostemon cablin) Sandalwood (Santalum album / spp.) Spikenard (Nardostachys jatamansi) Tobacco absolute (Nicotiana tabacum) Vanilla (Vanilla planifolia; absolute/extract) Vetiver (Chrysopogon/Vetiveria zizanoides)