Botanical Scent Pyramid Engineering: Top, Heart & Base Note Volatility Curves in Beeswax

1. Vapor Pressure Physics of Pure Essential Oils

Synthetic fragrance oils are engineered with petrochemical fixatives (DEP, benzyl benzoate, synthetic musks) that artificially flatten evaporation curves. When formulating exclusively with 100% pure steam-distilled and cold-pressed essential oils, evaporation from a 56°C beeswax melt pool or a curing soap bar is governed by Raoult's Law and component vapor pressure (P°ᵢ):

P_i = x_i · γ_i · P°_i(T)

Where xᵢ is the mole fraction of the terpene in the beeswax-coconut lipid phase and γᵢ is the activity coefficient.

2. FtaaE Tri-Phase Botanical Chord Architecture

| Olfactory Tier | Terpene Class & Molecular Weight | Vapor Pressure @ 25°C | Representative FtaaE Botanical Oils | Target Chord Ratio |

| :--- | :--- | :--- | :--- | :--- |

| Top Notes (Head) | Monoterpenes (C₁₀H₁₆, 136.2 g/mol) | 1.20 – 2.10 mmHg | Sweet Orange, Lemon, Grapefruit, Bergamot, Scotch Pine | 20% – 30% |

| Heart Notes (Middle) | Oxygenated Monoterpenoids (152 – 196 g/mol) | 0.08 – 0.45 mmHg | French Lavender, Eucalyptus, Rosemary, Lemongrass, Peppermint | 45% – 55% |

| Base Notes (Fixative) | Sesquiterpenes & Phenols (164 – 222 g/mol) | 0.001 – 0.03 mmHg | Atlas Cedarwood, Clove Bud, Cinnamon Leaf, Patchouli, Vetiver | 20% – 30% |

3. Clay-Adsorption Fixation in Cold-Process Bar Soaps

In cold-processed bar soaps, volatile citrus top notes (d-limonene) are vulnerable to evaporation during the exothermic saponification phase. FtaaE pre-adsorbs the essential oil chord onto microporous kaolin or French green illite clay (2.5% w/w) for 12 hours prior to compounding:

soap_aroma_fixation_protocol:
  adsorbent_substrate: "Kaolin / Illite Mineral Clay (Particle size D50 < 4 microns)"
  pre_soak_ratio: "1 part Clay : 1.5 parts Essential Oil Chord"
  maturation_time_hours: 12
  addition_stage: "Folded at light trace (39.0°C)"
  retention_improvement_pct: "+42% volatile terpene retention after 28-day cure"

4. Olfactory Stability Verification Checklist

• Verify chord contains at least 20% low-volatility sesquiterpene or phenolic base notes.
• Conduct 14-day accelerated thermal aging test at 40°C to confirm zero top-note souring.
• Evaluate cold throw at 1.0 m distance and hot throw in a 25 m³ test chamber after 60 minutes of burn time.