Influence of processing methods on the tocopherol homologues, stigmasterol and volatile chemical profiles of coconut oils
Shunmugiah Veluchamy Ramesh, Raveena Natakkakath Kaliyathan, Erepadickal Purushothaman Ashamol, Kodoth Sharanya, Musuvadi Ramarathinam Manikantan, Murali GopalAbstract
BACKGROUND
Processing can substantially influence the chemical composition and quality characteristics of coconut oils. The present study investigated the influence of different processing methods on tocopherol homologues, stigmasterol, and volatile/semi‐volatile chemical profiles of coconut oils.
RESULTS
Virgin coconut oils produced by hot processing (VCO‐Hot), natural fermentation (VCO‐Fer), and expeller extraction from dehydrated coconut gratings (VCO‐EDG), along with copra oil, were comparatively evaluated. δ ‐, β + γ ‐, and α ‐tocopherols and stigmasterol were quantified by high‐performance liquid chromatography with photodiode array detection (HPLC‐DAD), while volatile and semi‐volatile constituents were characterized by direct gas chromatography–mass spectrometry (GC–MS). Significant differences ( P < 0.05) were observed among the processing methods. VCO‐Hot showed the highest concentrations of δ ‐tocopherol (0.53 ± 0.05 mg 100 mL −1 ), α ‐tocopherol (0.13 ± 0.03 mg 100 mL −1 ), and stigmasterol (33.25 ± 0.77 mg 100 mL −1 ), whereas VCO‐EDG showed the lowest concentrations, with β + γ ‐tocopherol not detected. Distinct processing‐dependent chemical profiles were observed. Copra oil was characterized by oxidation‐related ketones and hydrocarbon derivatives, VCO‐EDG by lactone‐rich compounds, VCO‐Fer by fatty acid ester derivatives, and VCO‐Hot by a diverse profile dominated by 3‐undecanone, together with lactones and terpenes.
CONCLUSION
Processing method significantly influenced the concentrations of measured lipid‐soluble compounds and the volatile/semi‐volatile chemical profiles of coconut oils. Among the oils evaluated, VCO‐Hot exhibited the highest concentrations of the measured tocopherols and stigmasterol and a diverse volatile profile. These findings provide additional compositional insights into processing‐related differences in coconut oils and may support the selection and optimization of processing methods. © 2026 Society of Chemical Industry.