Rapid and simultaneous analysis of 16‐O‐methylcafestol and sterols as markers for assessment of green coffee bean authenticity by on‐line LC‐GC

An on‐line LC‐GC method for analysis of 16‐O‐methylcafestol (16‐OMC) and total sterols in oils obtained from green beans of Coffea canephora (Robusta) and C. arabica (Arabica) has been developed. HPLC pre‐separation of the transesterified lipids allows quantification of the content of 16‐OMC. The fraction containing the sterols is transferred to on‐line GC analysis. The results obtained for Arabica and Robusta samples were in good agreement with literature data obtained by classical analytical procedures. The method allows rapid and simultaneous determination of two markers (16‐OMC and Δ5‐avenasterol) proposed for authenticity assessment of coffee beans and overcomes time‐consuming sample pretreatment steps.