Table 2.
A comparison of methods used for fatty acid analysis
| Method | Traditional extraction or in situ | Approx. minimum sample mass (g) | Description | Approx. solvent volumes | Number of sample transfers during transesterification | Reference |
|---|---|---|---|---|---|---|
| Sub-microscale in situ (“SMIS”) | in situ | 0.00025 | FAME prepared by exposing total sample to BF3 in MeOH, heated at 100 °C for 1 h, followed by a two-step phase separation | 0.9 mL | 2 | This study |
| Micro-direct | in situ | 0.002 | FAME prepared by exposing total sample to HCl in MeOH, heated at 110 °C for 2 h | 5 mL | ~3 | Viga and Grahl-Nielsen [21]; Theimann et al. [6] |
| Ackman | Traditional extraction | 0.2 | Lipids extracted in non-polar solvent. FAME prepared using BF3 in MeOH, heated at 100 °C for 1 h | 20 mL | 3 | Ackman [2] |
| AOCS | Traditional extraction | 0.2 | Lipids extracted in non-polar solvent. FAME prepared first using NaOH in MeOH, heated at 100 °C for 5 min., then using BF3 in MeOH, heated at 100 °C for 1 h | 25 mL | ~5 | AOCS Method [5]; Barker [3] |
| AOAC | Traditional extraction | 0.2 | Hydrolytic lipid extraction. FAME prepared first using NaOH in MeOH, heated at 100 °C for 5 min, then using BF3 in MeOH, heated at 100 °C for 1 h | 25 mL | ~5 | AOAC Method [4] |
Data adapted from Theimann [6]