Chemometric analysis of mid infrared and gas chromatography data of Indonesian nutmeg essential oils

Nutmeg, provided by tree native to Moluccas, is widely interesting for Indonesia essential oil production. 21 hydrocarbon and oxygenated compounds are controlled by industrial perfumers in nutmeg samples. Samples of nutmeg essential oils (n = 26) from different geographic origins (Sanger, Siau and Minahasa for the Sulawesi region and Ambon and Ternate for little islands of the Molucca region) show high variation of concentrations of these compounds. The evolution of composition during the extraction of essential oil was studied and has shown the importance of this parameter for the nutmeg essential oil quality. Chemometric treatment of gas chromatographic–mass spectrometry (GC–MS) data was assessed for the differentiation of geographical origin and maturity of the nutmeg. Results were compared to those obtained by MID-IR analysis. Chemometric MID-IR spectra treatments conduce to similar results than those obtained by GC–MS which is a time consuming analytical technique. Therefore, MID-IR associated to chemometric analyses constitutes a robust and helpful fast method for authentication of nutmeg essential oils.

► Study of influence of geographical origin and maturity of nutmeg nuts on their essential oils.
► Study of changes in chemical composition during the oil extraction.
► The results obtained by MID-IR analyses are in good concordance with GC–MS results.
► MID-IR coupled to chemometric analyses could be an alternative to time-consuming GC–MS method.
► MID-IR coupled to chemometric analyses is a robust and helpful fast method for oil authentication.