GC-MS, FTIR, Sensory analysis 

1. Gas Chromatography–Mass Spectrometry (GC-MS)

Purpose:

  • Identify and quantify chemical constituents in agarwood oil.
  • Detect sesquiterpenes, chromones, and other aromatic compounds.

Procedure:

  1. Dilute agarwood oil in a suitable solvent (e.g., hexane).
  2. Inject sample into GC-MS instrument.
  3. Separate compounds based on volatility and polarity.
  4. Detect and identify compounds via mass spectral library matching.

Applications:

  • Determine chemical fingerprint of different grades.
  • Authenticate species and origin.
  • Compare extraction methods (steam vs CO₂).

Key Indicators:

  • High-quality oils: rich in agarospirol, jinkohol, α-agarofuran, α-guaiene.
  • Super-grade oils show higher concentration of sesquiterpenes and chromones than sinking or incense-grade oils.

2. Fourier Transform Infrared Spectroscopy (FTIR)

Purpose:

  • Analyze functional groups in resin or oil.
  • Identify chemical bonds (C=O, C-H, aromatic rings) associated with resin quality.

Procedure:

  1. Place small sample of resin or oil on FTIR instrument (usually KBr pellet or ATR method).
  2. Scan in infrared range (4000–400 cm⁻¹).
  3. Compare absorption peaks to reference spectra of authentic agarwood compounds.

Applications:

  • Confirm resin authenticity and purity.
  • Monitor resin maturation or degradation.
  • Detect adulteration or contamination.

Key Indicators:

  • Peaks around 1730–1740 cm⁻¹: ester/carbonyl groups
  • Peaks around 1600 cm⁻¹: aromatic compounds
  • Peaks around 2900 cm⁻¹: CH stretching in terpenes

3. Sensory / Organoleptic Analysis

Purpose:

  • Evaluate fragrance quality, intensity, and complexity.
  • Assess suitability for perfume, incense, or ceremonial use.

Procedure:

  1. Use trained panelists to smell resin or oil samples.
  2. Record aroma descriptors: woody, balsamic, sweet, fruity, smoky.
  3. Optionally, heat small chips or warm oil to release volatile compounds.
  4. Grade samples based on strength, persistence, and quality of fragrance.

Applications:

  • Confirm consumer-perceived quality.
  • Differentiate grades: super-grade oils = richer, complex aroma; incense-grade = simpler fragrance.
  • Complement chemical analysis (GC-MS, FTIR) for holistic quality assessment.

Key Indicators:

  • Intensity: strength of scent release
  • Complexity: number of distinguishable aromatic notes
  • Persistence: how long fragrance lasts after burning or warming

4. Combined Quality Assessment Workflow

  1. Sample collection: resin or oil from chips, sinking grade, or super grade.
  2. GC-MS: identify chemical profile → quantify sesquiterpenes & chromones.
  3. FTIR: confirm functional groups → purity and resin fingerprint.
  4. Sensory analysis: validate fragrance intensity, complexity, and appeal.
  5. Data integration: classify grade, detect adulteration, and optimize harvesting/extraction methods.

5. Best Practices

  • Use authentic reference standards for GC-MS and FTIR.
  • Train sensory panelists for consistent aroma evaluation.
  • Combine instrumental analysis + sensory evaluation for robust quality grading.
  • Document chemical and sensory data per batch to guide plantation management and premium pricing.