TABLE 5.
Relative intensity ratio (RIR), direct transfer efficiency (DTE), and precursor contribution index (PCI) quantitative analysis.
| Index | Avg (SBSE) | Avg (PY) | Avg (Smokiness) | DTE (Smk/SBSE) | RIR (Smk/SBSE) | RIR (Smk/PY) | PCI (PY/Smk) | Notes |
|---|---|---|---|---|---|---|---|---|
| 1,2,3-Propanetriol, 1-acetate | 0.0709 | 0 | 26.54 | 374.3 | 374.3 | — | 0 | High-efficiency release, no thermogenesis |
| 2-Propanone, 1-hydroxy- | 0 | 2.36 | 14.32 | — | — | 6.07 | 0.165 | Complete thermogenesis, partial entry into flue gas |
| 3,7,11,15-Tetramethyl-2-hexadecen-1-ol | 0.071 | 0 | 0.0438 | 0.617 | 0.617 | — | 0 | Present in leaves but limited release |
| Acetic acid | 0.0033 | 1.22 | 12.86 | 3,897 | 3,897 | 10.54 | 0.095 | Extremely enriched in flue gas, primarily thermogenic |
| Butanoic acid, 2-methyl- | 0.014 | 0 | 0.2209 | 15.78 | 15.78 | — | 0 | Primordial release type |
| Butanoic acid, 3-methyl- | 0.0319 | 0 | 0.5362 | 16.8 | 16.8 | — | 0 | Primordial release type |
| Glycidol | 0.0466 | 0 | 13.17 | 282.6 | 282.6 | — | 0 | High-efficiency release, non-thermogenic |
| Hydroxylamine | 0.0493 | 0 | 16.93 | 343.4 | 343.4 | — | 0 | High-efficiency release, non-thermogenic |
| Neophytadiene | 35.12 | 1.26 | 15.44 | 0.439 | 0.439 | 12.25 | 0.0816 | High in-situ, low transfer, weak thermogenesis |
| Phenol | 0.1435 | 1.1812 | 2.221 | 15.48 | 15.48 | 1.88 | 0.532 | Significant thermogenesis + high-efficiency release |
| Pyrazine, methyl- | 0.0481 | 0 | 1.939 | 40.31 | 40.31 | — | 0 | High release efficiency, thermal generation |
| Pyrazine, 2,6-dimethyl- | 0.0466 | 0 | 2.463 | 52.85 | 52.85 | — | 0 | High release efficiency, thermal generation |
| Pyrazine, 2-ethyl-5-methyl- | 0.0305 | 0 | 0.2839 | 9.31 | 9.31 | — | 0 | High release efficiency, thermal generation |
| Pyridine, 3-(1-methyl-2-pyrrolidinyl)-, (S)- | 355.15 | 20.87 | 653.89 | 1.84 | 1.84 | 31.33 | 0.0319 | Primarily from primary release, minor thermal generation |
| Pyridine, 3-(3,4-dihydro-2h-pyrrol-5-yl)- | 3.032 | 1.7698 | 42.97 | 14.17 | 14.17 | 24.28 | 0.0412 | High release efficiency + moderate thermal generation |
The Relative Intensity Ratio (RIR) measures the distribution preference of a component across different samples: if the SBSE, value is 0, only the presence or absence of PY, formation is considered; the opposite applies. Direct Transfer Efficiency (DTE) evaluates the ability of existing components in tobacco leaves to transfer into smoke: If DTE ≈1: essentially equal transfer; If DTE >> 1: potential concentration effect or co-distillation-enhanced release; If DTE << 1: prone to degradation or retention in residues. Thermal Generation Factor (TGF) evaluates whether the compound is primarily newly generated during pyrolysis: If TGF >> 1: Significant thermal generation; If SBSE, 0 and PY > 0: Fully thermally generated. Precursor Contribution Index (PCI) identifies certain “indirect products” that show no signal in SBSE, or PY, but appear in Smokiness.