7-Hydroxy-3,7-dimethyloctanal · 7-HDO · CAS 107-75-5
Lili ki khushbu (لیلی کی خوشبو) — the benchmark synthetic muguet molecule, solving perfumery's oldest puzzle since 1908. Lily of the valley cannot be distilled; hydroxycitronellal is its voice. Used in Diorissimo, Chanel No.5, and Quelques Fleurs — now available to Pakistani formulators at Bio Shop™ Pakistan. IFRA-restricted; use with back-calculation.
Colourless to pale yellow, slightly viscous liquid · BP ~257°C · MP 22–23°C (may congeal in cool weather)
Density / Refractive Index
Sp. Gr. 0.918–0.923 at 25°C RI: 1.447–1.450 at 20°C
Flash Point / Log P
Flash point ≈100°C (closed cup) Vapour pressure 0.547 Pa at 20°C
Solubility
Soluble in ethanol, DPG, fixed oils · Practically insoluble in water and glycerin · Requires solubiliser for aqueous formulations
Halal Status
✓ Halal — 100% synthetic via citronellal hydration; plant-derived precursor (lemongrass). No animal inputs, no ethanol, no fermentation
Odour Character
Sweet, clean, dewy muguet (lily of the valley); lilac; linden blossom; green melon · Lili ki khushbu (لیلی کی خوشبو) · Aqueous-floral, transparent white floral
Odour Threshold
~4.8 ng/L air — moderate threshold; requires 5–25% in compound for full muguet effect. Not an ultra-trace material; effective at moderate dosing
IFRA Status (51st)
⚠ IFRA RESTRICTED — category-specific limits apply. Fine fragrance max ~2.1% product; body lotion ~0.6%; reed diffuser Cat. 10A significantly reduced. Back-calculate at each use
EU Allergen Status
⚠ EU LISTED ALLERGEN — mandatory declaration above 0.001% in leave-on / 0.01% in rinse-off (EU Cosmetics Reg. 1223/2009, Annex III)
Synthesis & Origin
Acid-catalysed hydration of citronellal (from lemongrass, C. flexuosus). Knoll & Co. synthesis 1905; commercial since 1908. BASF, Zhejiang NHU, Firmenich production
Shelf Life (sealed)
24–36 months sealed, cool, dark. Note: may solidify below 22°C in Lahore winters — warm gently before use. Acid value <2.0 mg KOH/g is quality indicator
Introduction
Muguet ki Khushbu — The Lily Molecule
Hydroxycitronellal is the molecule that gave a voice to silence. Lily of the valley (Convallaria majalis) — called muguet in French perfumery — is one of the most revered floral scents in the world, yet the delicate bell-shaped flower stubbornly refuses to yield its perfume to steam distillation or commercial solvent extraction. When German chemists at Knoll & Co. first synthesised hydroxycitronellal in 1905 and brought it to commercial scale by 1908, they solved one of perfumery's oldest challenges: how to place into a bottle the fresh, dewy, spring-morning luminosity of a flower that had always remained just beyond reach. More than 115 years later, hydroxycitronellal remains the benchmark reference for the lily of the valley note, a founding material of modern floral perfumery, and one of the most widely recognised fragrance ingredients in global commerce. Its landmark appearances in Diorissimo (Edmond Roudnitska, 1956), Quelques Fleurs (Houbigant, 1912), Chanel No.5 (Ernest Beaux, 1921), and Arpège (Lanvin, 1927) mark it as the essential white floral material of the 20th century.
Pakistan's fragrance market represents an extraordinary opportunity for hydroxycitronellal-based formulations. Pakistani consumers have a deeply ingrained preference for fresh floral accords — the chameli (jasmine) garland worn at weddings, the gulab (rose) attar dabbed behind the ears on Eid morning, the white floral mist spritzed before Jumu'ah. Hydroxycitronellal seamlessly extends and brightens all these beloved Pakistani floral traditions. Its clean, dewy muguet character evokes freshness, purity, and the gentle arrival of spring rains known as barsat. When paired with PEA (phenyl ethyl alcohol), linalool, and hedione, it creates modern floral compounds that resonate strongly with urban Pakistani women aged 18–45 who seek sophisticated international-style fragrances at accessible price points. Its IFRA-restricted status requires back-calculation for each product type, but within those limits it remains one of the most commercially indispensable floral materials available.
Bio Shop™ Pakistan — Sourcing Note
Bio Shop™ Pakistan stocks Hydroxycitronellal at perfumery grade ≥97% GC purity — the professional specification used by international fragrance houses. Supplied as a colourless to pale yellow, slightly viscous liquid. Note: may congeal below 22°C in Lahore winters — warm sealed container in a warm water bath (not above 35°C) before use. Typical compound use: 5–25% in attar/fine fragrance compound; 0.3–0.6% in body lotion or rinse-off products. Always back-calculate against IFRA 51st Amendment limits for your product category. GC certificate with batch documentation available. Visit bioshop.pk/products/hydroxycitronellal for current stock and pricing.
Formula / MWC₁₀H₂₀O₂ · 172.26 g/mol · Medium-chain aliphatic aldehyde
Functional GroupsPrimary aldehyde (−CHO) at C-1 · Tertiary alcohol (−OH) at C-7 · Gem-dimethyl at C-7
Degree of Unsat.1 — the aldehyde C=O only; no C=C double bonds (unlike citronellal precursor)
StereochemistryAsymmetric centre at C-3 (racemate in commerce); both enantiomers have similar muguet odour
Synthesis RouteAcid-catalysed Markovnikov hydration of citronellal (C6=C7 double bond) with dil. H₂SO₄, 40–60°C; yield ~85%; purity ≥97% GC after vacuum distillation
Precursor OriginCitronellal from lemongrass (Cymbopogon flexuosus, China/Nepal) or citronella (C. nardus, Sri Lanka/Java) by fractional distillation
Olfactory ReceptorPrimary target: OR1G1 (muguet receptor family) · Dual polar interaction via aldehyde + hydroxyl groups
Urdu / PakistanLili ki khushbu (لیلی کی خوشبو) — the scent of lily · تازہ گلابی پھولوں کی مہک — fresh white flower fragrance
Grade & Purity Profiles
Four Commercial Grades
Hydroxycitronellal is available in three legitimate grades plus the adulterated material sometimes circulating in the Pakistan grey market. Higher purity delivers cleaner, brighter muguet character with fewer harsh fatty side-notes. Bio Shop™ Pakistan stocks Perfumery Grade (≥97% GC) — the professional specification for fine fragrance, attars, and quality personal care formulations.
Acid value ≤2.0 · RI 1.447–1.450 · Sp. Gr. 0.918–0.923
"The professional standard for all fine fragrance, attar, and personal care applications. Clean, sweet, dewy muguet on blotter; transparent white floral in the heart; soft powdery tenacity in the dry-down. Bio Shop™ Pakistan primary stock. GC certificate with each batch. Use at 5–25% in compound."
Functional Grade · Soap & Detergent
Technical Grade
93–96% GC · Higher colour · Soap, detergent, air freshener use
GC Purity
93–96%
Trace impurities tolerated in functional fragrance
"Suitable for soap bars, detergent compounds, air fresheners, and fabric softeners where minor impurities are acceptable. Slightly harsher opening note versus perfumery grade; lower cost per kg. In fabric applications, the substantivity benefits are fully retained at this grade. Not recommended for fine fragrance or premium attars."
Heavy metal limits; microbiological testing; FCC documentation
"FEMA GRAS 2583 approved: up to 16 mg/kg chewing gum, 10 mg/kg baked goods, 9.4 mg/kg hard candy, 3.5 mg/kg soft drinks. Flavour character at these trace levels is sweet, light floral, slightly watery-citrus. Do NOT use standard fragrance grade in food applications — FCC documentation with heavy metal data required."
⚠ Avoid Without Verification
Adulterated / Unknown
Pakistan grey market · DEP dilution · Citronellal substitution · Off-spec material
"Common adulterants: DEP dilution (odourless, reduces SG below 0.90), citronellal substitution (smells citrus-lemon, not muguet; BP ~207°C vs 257°C), and mixed floral aldehyde blends sold as pure HC. Blotter test: pure HC gives sweet, clean muguet with good tenacity. Citrus/harsh/flat character = adulteration. Always demand COA with GC, SG, and RI values."
Dosage Science
Concentration Behaviour
Hydroxycitronellal has a relatively high odour threshold of 4.8 ng/L air, meaning it requires moderate dosing to achieve full olfactory effect — it is not an ultra-trace ingredient. At low levels it acts as a transparent floraliser, brightening and lifting adjacent materials. At 10–25% in the compound, it becomes the dominant muguet voice. This relatively high threshold is an asset: the material adds transparent floral volume without competing aggressively with other ingredients, making it a superb "space filler" for white floral accord construction. Note that IFRA 51st Amendment limits must be respected via back-calculation from the finished product category limit.
Below 1% in CompoundSub-Threshold Freshener
Minimal odour contribution at this level; subtle moistening and freshening of dry accords without identifiable muguet character. Useful as a background freshener in oriental or woody compositions where a trace white-floral transparency is wanted without a visible floral note
1–5% in CompoundSoft Floral Lift
Transparent aqueous freshness; soft floral brightness; enhances and brightens other florals without dominating. Ideal as a floraliser in complex rose, jasmine, or peony accords where muguet transparency is wanted but not as the leading character. Perfect for the floraliser role in oud-rose attars
5–10% in CompoundClear Muguet Emergence
Distinct, clean muguet note; dewy white-floral; lilac facet becomes prominent. Ideal for white floral support roles in peony, lilac, gardenia accords; adds naturalness and luminosity. A 5–8% addition to a rose-jasmine base transforms a traditional oriental into a contemporary floral-oriental
10–15% in CompoundFull Muguet Heart
Dominant lily of the valley character; clean depth and radiance. The muguet becomes the primary message of the composition. Suitable for the white floral heart of feminine EDPs, spring-themed fragrances, and traditional muguet attars for Pakistani wedding-occasion use (lili bahar direction)
15–25% in CompoundIntense Muguet Soliflore
Dense, immersive muguet; high radiance; slightly aqueous-green. HC as lead or co-lead material in the composition, as used by Roudnitska in Diorissimo at ~10% of finished EDP. At this level in compound, verify IFRA compliance against finished product category limits — EDP at 20% load = 3–5% HC in finished product, verify against 2.1% fine fragrance limit
Above 25% in CompoundHigh Dose — IFRA Check Required
Powerful, immersive muguet; some aldehyde sharpness at highest doses. Used only for speciality muguet bases, testing, and applications where product dilution ensures IFRA compliance. At 25% in a compound used at 1% in a rinse-off product, finished product concentration is 0.25% — well within 0.6% rinse-off limit. Always calculate finished product concentration before production
Sensory Analysis
Olfactory Evolution
Opening · 0–5 min
Dewy Aqueous Floral
Hydroxycitronellal opens with a quality of exceptional cleanness that no other aroma chemical replicates — a soft, dewy, almost liquid freshness that perfumers call "aqueous-floral". There is sweetness, but it is restrained, transparent, and entirely free of the honeyed heaviness of jasmine or the ripe fruitiness of peach. For the Pakistani nose accustomed to the dense, rich florals of rose attar and chameli, this introduction delivers a new vocabulary: the vocabulary of European spring, of morning dew, of petals too fragile to touch. In Pakistan's warm spring season (bahar), when the air itself carries a freshness after monsoon or spring rains, this opening maps instinctively onto the cultural experience of taazgi (تازگی — freshness), making it immediately legible and desirable to Pakistani female consumers.
Heart · 5–30 min
Full Muguet Presence
The core muguet note emerges fully within 5–10 minutes — a crystalline white floral that is simultaneously luminous and radiantly clean. Lilac and linden blossom nuances appear as facets within the dominant lily character. At higher concentrations (above 10% in compound), this heart phase delivers what perfumers describe as the "immersive" quality associated with Diorissimo: you are not smelling a muguet note, you are standing ankle-deep in lily of the valley after morning rain. On Pakistani skin at 38–40°C summer temperatures, the moderate vapour pressure of hydroxycitronellal produces excellent diffusion — the white floral heart radiates generously from the skin, creating a natural sillage appropriate for wedding, Eid, and formal social occasions. This phase maps onto the cultural ideal of taaza lili (تازہ لیلی) — fresh lily.
Dry-down · 30 min–2 hr
Powdery Clean Warmth
As the compound evolves on skin, hydroxycitronellal softens into a slightly powdery, abstract clean-floral warmth — elegant, neutral, and suitable for all social settings including conservative ones. The gem-dimethyl group at C-7, combined with the tertiary hydroxyl's hydrogen-bonding with skin proteins, creates excellent substantivity: the molecule lingers on warm skin and integrates into the wearer's natural warmth. This dry-down quality — sometimes called "skin muguet" — is culturally appropriate for Pakistani women who wear fragrance to prayers, to family gatherings, and to professional settings where an obvious sillage would be unwelcome. The transition is seamless, the character neutral and universally pleasant.
On Fabric · Next Day
Fabric Ghost
Hydroxycitronellal's most commercially significant property in the Pakistani context may be its exceptional substantivity on textile fibres. The C-7 hydroxyl group forms hydrogen bonds with cellulose in cotton — the primary fabric of shalwar kameez, dupattas, and chunnis — and with silk proteins, creating a lasting clean-floral shadow that persists for 6–12 hours on washed fabrics. Pakistani consumers who apply fragrance-containing hydroxycitronellal to their clothing or who wash garments with soap containing it notice a pleasant, clean white floral warmth throughout the day. This fabric-longevity property explains why hydroxycitronellal is one of the most widely used ingredients in soap, detergent, and fabric softener fragrances worldwide — and represents a significant commercial opportunity for Pakistani personal care brands in the laundry and home cleaning category.
MuguetLily of the ValleyAqueous-FloralDewyLilacLinden BlossomGreen MelonClean White FloralLili (لیلی)Powdery Warmth
Formulation Accords
Three Complete Formulas
Three production-ready formulas from the Bio Shop™ Pakistan reference document — exact weights, exact percentages. All ingredients available at bioshop.pk. Formula 1 is a DPG muguet attar (no alcohol — halal for all markets). Formula 2 is a spring floral EDP compound using Perfume Premix as the sole alcohol base. Formula 3 is a muguet body lotion. ⚠ IFRA NOTE: Hydroxycitronellal is IFRA-restricted (51st Amendment). Always verify finished product concentration against IFRA category limits before commercial production.
Lili Bahar Attar · لیلی بہار عطر
Muguet-Rose Oil Attar · DPG-based, no alcohol · 100g batch · Roll-on or dabba · Pakistani women 18–40, wedding season, Eid
⚠ IFRA CHECK: HC at 25% in compound. If used as attar at 100% (neat on skin), verify this level against IFRA Category 1 fine fragrance limit (~2.1% in product does not apply to neat attar oil — for neat oil application, consult IFRA Standards Category 3/4 as applicable). Recommended: blend attar to 10–20% in DPG before use for safe skin application. | Weigh DPG into clean glass vessel first. Add all ingredients in listed order, stirring gently. Seal and macerate 48–72 hours at room temperature. Filter if cloudy. Longevity: 6–8 hours. Character: dewy muguet with rose heart above warm sandalwood-musk base.
Bahar Noor EDP · بہار نور
Spring Muguet-Floral EDP Compound · Perfume Premix base · 100g compound · Urban women 20–45 · Gulf export / bridal season
✓ IFRA COMPLIANT: HC at 0.5% in finished lotion (leave-on Category 3 limit ~0.6%). Within safe-use limits — no back-calculation adjustment needed. | EU EXPORT NOTE: HC must be declared on EU cosmetic labels as a fragrance allergen (above 0.001% leave-on threshold — 0.5% far exceeds this; declaration required). | Method: Warm carrier oils (MCT + almond + jojoba + vitamin E) to 40°C. Dissolve fragrance materials (HC, linalool, PEA, hedione) into DPG. Combine with stirring. Add emulsifying wax; blend to homogeneous. Cool to 30°C; add preservative; adjust pH 5.5–6.5. Performance: soft muguet-floral character on skin, 3–4 hours longevity.
Synergies
Classic Pairings
Hydroxycitronellal is extraordinarily compatible with virtually all standard fragrance materials. The pairings below represent the most commercially valuable and technically validated combinations for Pakistani formulation, drawn directly from the reference document. Note Schiff base reactivity: in alcoholic fragrances, HC + methyl anthranilate/Aurantiol will partially form Aurantiol in situ over time — this is intentional in some formulas.
Green, cyclamen, petalic, crisp — sharper and more powerful than HC; less dewy sweetness; more angular green character
Threshold / IFRA
~2.5 ng/L — more potent · ⚠ IFRA Restricted (less strict than HC) · Available at bioshop.pk/products/cyclamen-aldehyde
Use With HC
Essential pairing: 3:1 ratio (HC:Cyclamen Ald) creates the foundational muguet accord of modern perfumery — complementary receptor activation produces emergent naturalness
Pakistan Application
Used at 8% in the Lili Bahar Attar formula; 5% in Bahar Noor EDP. Adds green-petalic crispness that prevents HC from reading as synthetic-sweet
Verdict: Best companion, not substitute. HC + Cyclamen Aldehyde at 3:1 is the gold standard muguet pairing — together they exceed either alone in naturalness and complexity.
More powerful, diffusive lily-cyclamen; less dewy-aqueous than HC; stronger and more tenacious at equivalent use levels; slightly less transparent
Threshold / IFRA
~0.45 ng/L — much more potent · ✓ IFRA Permitted (no restriction in current standards) · Not EU listed allergen — formulation advantage for EU export
Use With HC
As a potency booster: 0.3–0.5% Lilial achieves similar olfactory effect to 1–2% HC. Can partially replace HC in formulas needing stronger muguet impact with lower allergen risk
Pakistan Application
Useful for rinse-off products where higher potency at lower dose is commercially advantageous; also for EU-export personal care where HC allergen declaration is a barrier
Verdict: Higher-potency, IFRA-unrestricted alternative. Use when stronger muguet impact per gram is needed or when EU export allergen avoidance is a priority. Note: Lilial has its own IFRA monitoring status — verify current standards.
Historically the most powerful muguet material — more diffusive and longer-lasting than HC; intense, immersive lily character. No longer commercially usable
Threshold / IFRA
~0.31 ng/L — extremely potent · ❌ IFRA PROHIBITED (51st Amendment) — must not be used in any product. Known strong dermal sensitiser
Relevance to Pakistani Formulator
Historical reference only. Classic perfumes that used Lyral (pre-51st Amendment) must be reformulated; HC + Cyclamen Aldehyde + Florol® is the recommended replacement system
Pakistan Market Note
Grey market material may still circulate in Pakistan labelled as "muguet base" or unlabelled. Do not use — zero tolerance for prohibited ingredients in products for any market
Verdict: Do NOT use. ❌ IFRA PROHIBITED. Reference only. Any supplier offering it for formulation use should be avoided entirely.
Florol® (Tetrahydromuguol)
Aliphatic Alcohol · Constitutional isomer of HC · Muguet-Watery · Non-Allergen
Aroma vs. HC
Similar muguet character; slightly more watery and less sweet than HC; no aldehyde sharpness at high doses; olfactorily very close — the best non-allergen substitute
Threshold / IFRA
~2 ng/L · ✓ IFRA Permitted · NOT listed as EU allergen — the key advantage for EU export and diffuser applications
Use With HC
Blend at 50:50 ratio HC:Florol® to achieve muguet character while reducing HC level (and therefore allergen declaration threshold) in the finished product
Pakistan Application
Especially valuable for reed diffusers (where HC 51st Amendment Category 10A limits are significantly reduced), children's products, and EU-export personal care
Verdict: Best non-allergen substitute for HC. Structurally similar (constitutional isomer), olfactorily close, IFRA-permitted, non-EU-allergen. Use in diffusers, EU-export products, and sensitive-skin formulations.
Safety & Regulations
IFRA & Safety Overview
Educational summary of publicly available regulatory data as of 2024. Always consult the current IFRA Standards (51st Amendment, ifrafragrance.org), the ingredient Safety Data Sheet, RIFM Safety Database, and your regulatory advisor before commercial formulation. This document does not constitute regulatory or safety advice.
Hydroxycitronellal is subject to a Restriction Standard under the IFRA 51st Amendment (June 2023). It is neither prohibited nor freely permitted. Key limits: fine fragrance (leave-on skin, Cat. 3) ~2.1% in finished product; body lotion/cream ~0.6%; rinse-off (shampoo/body wash) ~0.6%; reed diffuser (Cat. 10A) significantly tightened. IFRA compliance deadlines: new creations from 30 March 2024; existing formulas reformulation by 30 October 2025. RULE: always back-calculate from product category. If compound is used at 20% in an EDP, HC may not exceed 2.1% ÷ 20% = 10.5% of the compound for fine fragrance compliance. Verify with current IFRA Standards (ifrafragrance.org).
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EU Allergen — Mandatory Declaration Required
Hydroxycitronellal is listed as one of the 26 regulated fragrance allergens under EU Cosmetics Regulation 1223/2009, Annex III. When present in leave-on products above 0.001% (10 ppm), or in rinse-off products above 0.01%, it must be declared by name in the ingredients list. This applies to all products exported to the EU or UK. Pakistani manufacturers exporting to European markets MUST include "Hydroxycitronellal" in the INCI ingredient declaration on the product label when the thresholds are exceeded. The body lotion formula in this document (0.5% HC in finished product) requires EU allergen declaration. Monitor ongoing EU regulation amendments; the proposed expanded allergen list may broaden requirements further.
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Pakistan DRAP & Halal — Fully Compliant
No current restriction under Drug Regulatory Authority of Pakistan (DRAP) cosmetics guidelines for domestic use. Pakistani formulators selling in the domestic market may use hydroxycitronellal within IFRA limits. Halal status is fully confirmed: hydroxycitronellal is produced 100% by chemical synthesis beginning from citronellal, derived from steam distillation of lemongrass (Cymbopogon flexuosus) or citronella grass — entirely plant-based raw materials. Synthesis uses dilute mineral acid (H₂SO₄) and water only; no animal-derived materials, no ethanol, no fermentation, no haram substance at any stage. The finished compound is itself an aldehyde-alcohol, not dissolved in ethanol. For formal halal certification of a finished product, PHA (Pakistan Halal Authority) documentation based on the ingredient SDS is straightforward to obtain.
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Human Safety Profile — FEMA GRAS 2583
Acute oral LD₅₀ (rat) >5,000 mg/kg — practically non-toxic orally. Dermal LD₅₀ (rat) >5,000 mg/kg — practically non-toxic dermally. NOT phototoxic (non-furanocoumarin structure). NOT genotoxic (Ames test negative; in vitro clastogenicity negative). NOT carcinogenic (no evidence in available animal studies). NOT reproductively toxic at fragrance use levels. The primary human safety concern is skin sensitisation: hydroxycitronellal is a known contact sensitiser (LLNA positive; Draize test positive in guinea pig). This is why IFRA restrictions exist — to limit cumulative sensitisation risk. At IFRA-compliant use levels, the risk is managed. Avoid undiluted skin contact; use within IFRA category limits.
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Environmental — Readily Biodegradable
Hydroxycitronellal achieves >82% ready biodegradation within 28 days (OECD 301F test) — placing it among the more environmentally responsible floral aroma chemicals. The synthesis pathway from renewable lemongrass biomass (via citronellal) has a lower carbon footprint than many petrochemical-derived materials. Aquatic toxicity (EC50 Daphnia magna >75 mg/L) is moderate at high concentrations; PNEC 0.8586 μg/L (RIFM 2022). At typical consumer product use levels, real-world aquatic impact is negligible. For Pakistani formulators producing soap or detergent products disposed via wastewater systems, no special disposal precautions are required beyond normal regulatory compliance.
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Handling, Stability & Compatibility Precautions
The C-1 aldehyde group is the primary reactivity site. Susceptible to: (1) air oxidation to 7-hydroxycitronellylic acid (sour, harsh character) — store sealed with minimal headspace; (2) acetal formation in high-ethanol systems — reversible, minimal olfactory impact; (3) alkaline hydrolysis above pH 9 (use in pH 5–8 range; soap bars at pH 9–10 require antioxidant stabilisation); (4) Schiff base formation with primary amines (methyl anthranilate/aurantiol) — intentional in some formulas. NEVER use iron, copper, or brass vessels — metal ions catalyse aldehyde oxidation. Flash point ~100°C — avoid open flame during handling. Store in amber glass or HDPE; avoid UV exposure.
Handling & Storage
Storing in Pakistan's Climate
Temperature
Store below 25°C; optimal 18–22°C in air-conditioned stock room. Stable up to 40°C but aldehyde oxidation accelerates above this. Always use air-conditioned storage in Pakistan's hot seasons
Container Type
Amber glass (preferred UV protection) or opaque HDPE or food-grade stainless steel. NEVER iron, copper, brass, or aluminium without PE lining — metal ions catalyse oxidative degradation of the aldehyde group
Light Exposure
Keep away from direct sunlight and fluorescent UV. Inner room or dark cupboard mandatory. UV exposure accelerates both discolouration and aldehyde oxidation. Amber glass provides best protection for long-term storage
Shelf Life (sealed)
24–36 months from manufacture under optimal conditions; 18–24 months in typical Pakistani air-conditioned storage. Always conduct olfactory check before production use — sour, harsh, or rancid note indicates oxidation
Measuring Technique
Slightly viscous liquid — flows freely at 25°C. Use glass or HDPE measuring vessels. For attar/compound use (5–25%), a 0.01g precision balance is adequate. For trace applications (<1%), prepare a 10% DPG dilution for accurate measurement
Pre-use Handling
For 10% DPG dilution (trace applications): dissolve 10g HC in 90g DPG with gentle stirring at room temperature. Critical: 1g of 10% solution = 0.10g actual HC. Adjust formulas accordingly. Warm sealed container to 25°C before use if congealed
Lahore Summer & Winter
Summer (May–Aug): 38–45°C — active cooling essential; never store in vehicles; insulated boxes for transport. Winter note: HC MELTS AT 22–23°C — it may congeal as a white or pale solid in Lahore winters. Warm gently in a warm water bath (not above 35°C) before use; NEVER microwave or direct-heat
Karachi Coastal Climate
High humidity (75–90% RH year-round) accelerates container seal degradation and moisture condensation. Use double-sealed amber glass or HDPE; store in dehumidified room below 50% RH; seal immediately after each use; inspect containers periodically for moisture ingress. Minimise air headspace in partially used containers
⚠ Adulteration check: Genuine hydroxycitronellal (≥97% GC) is colourless to pale yellow, slightly viscous. Specific gravity 0.918–0.923 at 25°C — below 0.900 indicates DEP dilution. Blotter test: genuine material gives a sweet, clean, dewy muguet note. Citrus-lemon character = citronellal substitution (BP ~207°C vs authentic 257°C). Thin, one-dimensional flat floral = mixed aldehyde blend. Water test: 1 drop in 5mL distilled water should be essentially insoluble, forming a floating droplet with muguet aroma. Always request Certificate of Analysis with GC purity, specific gravity, and refractive index from any supplier.
FAQs
Frequently Asked Questions
Is hydroxycitronellal halal? What is its exact synthesis origin?+
Hydroxycitronellal is fully halal-compliant, and the evidence is unambiguous. (1) The compound is produced 100% by chemical synthesis — it is not extracted from any plant or animal source. (2) The synthesis begins with citronellal, a terpenoid aldehyde obtained by fractional distillation of lemongrass oil (Cymbopogon flexuosus, grown in China and Nepal) or citronella grass oil — entirely plant-based, agricultural-origin raw materials. (3) The synthesis reaction is acid-catalysed hydration: citronellal + water, using dilute sulfuric acid as catalyst at 40–60°C, followed by neutralisation with sodium carbonate and vacuum distillation. No animal-derived materials, no ethanol, no fermentation, and no haram substance is used at any stage. (4) The final product is itself a hydroxy-aldehyde compound — it is not a solution dissolved in alcohol; it is a pure aroma chemical. (5) For formal halal certification of a finished product incorporating hydroxycitronellal, the Pakistan Halal Authority (PHA) or an internationally accredited body can confirm compliance based on the ingredient SDS documentation. Bio Shop™ Pakistan can provide manufacturer halal compatibility documentation on request for professional accounts.
How do I verify the purity of hydroxycitronellal purchased in Pakistan?+
Four field verification methods are available without laboratory GC equipment. First, the blotter aroma test: apply one drop to a perfumer's blotter and allow 5 minutes. Genuine hydroxycitronellal should develop a distinctly sweet, clean, dewy, muguet-lily note — the universally recognisable lily of the valley character. A citrus-lemon or green character (not floral) indicates citronellal substitution. A thin, one-dimensional, flat or generic floral character indicates dilution or substitution with a mixed aldehyde blend. Second, the specific gravity test: at 25°C, authentic hydroxycitronellal reads 0.918–0.923 g/mL. Readings below 0.900 indicate DEP (diethyl phthalate) or mineral oil dilution. Third, the water solubility test: add one drop to 5mL distilled water — genuine HC is practically insoluble and forms a floating droplet smelling of muguet. Fourth, the evaporation tenacity test: genuine material on a blotter should retain a soft, powdery-clean floral note for several hours due to the C-7 hydroxyl group's hydrogen-bonding properties — adulterated or diluted material will fade quickly without this characteristic residual note. Always request a Certificate of Analysis (COA) with specific GC purity percentage, specific gravity, and refractive index values from any supplier.
How should I store hydroxycitronellal in Pakistan's hot and humid climate?+
Pakistan's two major climate zones present distinct challenges. For Karachi (coastal, 75–90% RH year-round): seal containers immediately after each use; use double-sealed amber glass or HDPE containers; store in a dehumidified storage room below 50% RH; inspect containers periodically for moisture condensation on inner surfaces; minimise air headspace by transferring to smaller containers as stock depletes. For Lahore (continental extremes — 38–45°C summers, cold winters): store below 25°C in an air-conditioned stock room year-round; never store in vehicles during summer; use insulated cooler boxes for any transportation; note a critical Lahore-specific issue — hydroxycitronellal has a melting point of 22–23°C and will congeal as a white solid in Lahore winters. To reliquefy: place the sealed container in a warm water bath at 30–35°C for 15–20 minutes; never microwave, never apply direct heat, and never heat above 40°C. For both locations: use amber glass or opaque HDPE; never use iron, copper, or brass vessels; minimise headspace; store away from UV light. Under these conditions, 24–36 months shelf life is achievable from manufacture date. Always conduct an olfactory check (sweet, clean, dewy muguet) before using in any production batch.
What is the correct usage level and when should I use pure vs. 10% DPG dilution?+
For attar and fine fragrance compounds where HC is used at 5–25% of the compound (i.e., 5–25g per 100g batch), use the pure form — measurement at this level is straightforward with a 0.01g precision scale and the cost savings versus a dilution are significant. For applications where HC is used at very low levels — below 1% in the compound, or when adding a trace amount to a finished product formula directly — prepare a 10% DPG dilution: dissolve 10g hydroxycitronellal in 90g DPG with gentle stirring until fully homogeneous at room temperature (it dissolves readily in DPG without heating). Critical formula adjustment: 1g of your 10% solution contains 0.10g actual hydroxycitronellal — adjust all formula quantities accordingly. For the body lotion formula in this document (0.5g HC in 100g lotion), pure HC is preferred since 0.5g is above the 0.1g practical minimum for a 0.01g balance. Regarding use levels: 1–5% in compound for floraliser role; 5–10% for clear muguet emergence; 10–25% for full muguet character; above 25% for speciality muguet base work — always verify IFRA compliance at the finished product level.
What does "anosmia to hydroxycitronellal" mean and how does it affect formulation?+
Specific anosmia to hydroxycitronellal — the inability to perceive it despite normal smell function — has been documented at relatively low population frequency, unlike the high-frequency specific anosmia to musk compounds. However, the phenomenon exists: some individuals perceive hydroxycitronellal as weak or characterless even at concentrations that are vivid to most people. This is thought to relate to individual variation in OR1G1 receptor expression. For Pakistani formulators, two practical implications arise. First, when testing a muguet formula, always get evaluation from multiple people and specifically ask if testers can "smell the lily"; a tester who cannot perceive the muguet character may have specific anosmia rather than poor formula quality. Second, when constructing a muguet accord for commercial products, building the accord with a blend of hydroxycitronellal, cyclamen aldehyde, and small amounts of linalool (which has broader olfactory receptor engagement) creates a more robust muguet experience for a wider consumer audience, including those with partial anosmia to HC. The characteristic tenacity and powdery drydown of hydroxycitronellal on fabric (which most people perceive regardless of any fresh-phase limitation) remains commercially valuable even for formulators working with partially anosmic consumers.
How do EU allergen regulations affect hydroxycitronellal? What must I do for EU export?+
Hydroxycitronellal is one of the 26 regulated fragrance allergens under EU Cosmetics Regulation 1223/2009, Annex III. This has direct commercial implications for Pakistani manufacturers exporting to EU or UK markets. For leave-on products (body lotion, cream, deodorant, perfume): if HC concentration in the finished product exceeds 0.001% (10 ppm), the word "Hydroxycitronellal" must appear in the product's ingredients list (INCI declaration), in addition to the general "Parfum" or "Fragrance" listing. The body lotion in this document at 0.5% HC is far above this threshold and MUST carry the EU allergen declaration. For rinse-off products (shampoo, body wash): the declaration threshold is 0.01% in the finished product. For Pakistan domestic market: no equivalent regulation currently exists. However, as a best practice for brands that may export or serve internationally aware consumers, voluntary EU-equivalent allergen labelling is recommended. The proposed EU expansion of the allergen list (from 26 to 82 ingredients) should be monitored; consult IFRA or an EU regulatory consultant before launching any new EU-export formulations. Note that IFRA 51st Amendment IFRA compliance (which limits use levels) is separate from EU allergen declaration requirements — both must be met independently for EU-export products.
Which Pakistani consumer segments respond best to hydroxycitronellal-led fragrances?+
Market experience in Pakistan identifies four consumer segments with the strongest affinity for muguet-floral fragrances built around hydroxycitronellal. First, urban women aged 18–35 in Karachi, Lahore, and Islamabad with exposure to international fragrance brands — this segment associates clean white florals with sophistication, femininity, and aspiration, and responds enthusiastically to muguet-forward compositions at accessible price points. Second, brides and wedding-occasion consumers (mehendi, baraat) seeking fresh, elegant floral scents that complement rather than compete with the heavy jasmine and rose garland traditions of Pakistani weddings — hydroxycitronellal's clean, dewy character is ideally positioned here as "international feminine refinement". Third, professional working women who prefer subtle, office-appropriate fragrances that project freshness without heavy sillage — the soft, transparent muguet drydown is culturally appropriate for conservative professional environments. Fourth, daily personal care buyers for body lotion, shampoo, and hair care — where the textile substantivity of hydroxycitronellal creates a commercially compelling "fresh laundry" experience that differentiates local products from generic competitors. Regionally: Lahore consumers tend to layer muguet notes over warmer oriental and rose bases; Karachi consumers prefer muguet in lighter, more aquatic-fresh structures that provide relief from coastal heat; Gulf-export buyers respond to muguet-oriental hybrids (lili + sandal + musk) for the Arab feminine market.
What Urdu names suit hydroxycitronellal products, and how does it perform in Pakistan's heat?+
Urdu naming for muguet-based products should draw on evocative poetic vocabulary rather than attempting to translate "lily of the valley" literally (which has no equivalent in traditional Pakistani botanical culture). Effective naming directions: لیلی بہار (Lili Bahar — Lily Spring) for spring seasonal attars; بہار کی سحر (Bahar ki Sehar — Spring Dawn) for a fresh feminine EDP concept; صبح کی تازگی (Subha ki Taazgi — Morning Freshness) for personal care products positioning daily freshness; گلابی اوس (Gulabi Oss — Rosy Dew) for a rose-muguet hybrid; بہار نور (Bahar Noor — Spring Light) for a premium EDP with cultural luminosity resonance. Seasonal positioning: launch muguet products for February–May (bahar — Pakistan's spring season) and September–October (the second fresh season post-monsoon, when consumers seek lighter fragrances). Hot weather performance of hydroxycitronellal in Pakistan is genuinely excellent: its moderate vapour pressure creates good diffusion from warm skin, projecting the muguet note outward pleasantly at 38–42°C. The C-7 hydroxyl's hydrogen-bonding provides substantivity that prevents rapid evaporation despite Pakistan's heat, meaning the composition lasts 4–8 hours on skin at summer temperatures — significantly longer than many comparable floral materials. Marketing language emphasising سرد اور تازہ (sard aur taaza — cool and fresh) resonates strongly with Pakistani consumer desires for heat-relief in summer fragrance experiences.
Everything on this page and substantially more — complete Markovnikov hydration mechanism with step-by-step synthesis diagrams, full structure-odour relationship analysis of the C-10 hydroxy-aldehyde scaffold, detailed molecular structure diagrams showing the dual functional group architecture (C-1 aldehyde + C-7 tertiary hydroxyl), historical timeline from Knoll & Co. 1905 to Diorissimo 1956 to present, RIFM safety data tables, natural occurrence analysis across aromatic plant families, FEMA GRAS 2583 food flavouring permitted use levels by category, full IFRA 51st Amendment category-by-category limit table with back-calculation worked examples, three advanced Pakistani market product concepts (Lili Bahar attar, Bahar Noor EDP, Subha Ki Taazgi body lotion), Schiff base chemistry section explaining the Aurantiol connection, textile substantivity science, and a comprehensive glossary of 18 key perfumery and regulatory terms — all compiled in one complete professional reference document.
