Discrimination between arabica and robusta coffee species on the basis of their tocopherol profiles

The tocopherol profiles of arabica and robusta coffee beans, both green and roasted, were ascertained. A solid-liquid micro-extraction method was used, and the quantification performed by normal-phase HPLC/diode-array/fluorescence detection. Regarding green arabicas, the mean contents were 2.7 ± 0.4 mg/100 g, for α-tocopherol, and 8.0 ± 0.9 mg/100 g, for β-tocopherol. For green robustas, mean values of 1.7 ± 0.3 and 2.1 ± 0.3 mg/100 g were found for α- and β-tocopherol, respectively. Generally, more than 90% of tocopherols remained after the roasting procedure, except for β-tocopherol in robustas, whose mean degradation was approximately 25% when expressed as dry weight. No γ-tocopherol was detected in any sample. The results show that tocopherol profile could be useful in the discrimination of arabica and robusta coffees (either green or roasted).