Analysis of aroma compounds in edible oils by direct Thermal Desorption GC/MS using slitted microvials

The determination of aroma compounds in edible oils (olive oil, sunflower oil, fish oil etc.) is important for manufacturers and vendors of these products. Especially off-flavors / off-flavours derived from unsaturated fatty acid degradation such as, for example, hexanal, 2-(E)-nonenal and 2,4-(E,E)-decadienal are of interest. These compounds can compromise the taste and therefore the quality of a product even in the ng/g concentration range…

This application note describes the direct thermal desorption of desirable and undesirable aroma compounds from edible oils.

The oil sample is placed in a micro-vial in which it is analysed by direct thermal desorption using a GERSTEL Thermal Desorption Unit (TDU). Volatile compounds are transferred to the GC/MS system while leaving the non-volatile oil matrix behind in the micro-vial, preventing it from reaching and contaminating the GC inlet and the GC column.  Microvials with a slit at 1 cm from the bottom were found to be the best suited providing efficient and repeatable analyte transfer and sensitive determination of a wide range of flavor-/flavour- active compounds.