Identification of strawberry (Fragaria × ananassa 'Rubygem') volatiles using various SPME fibres by GC/MS

Strawberry aroma is unique, highly desirable, and depends on many factors such as genetic variability within the species, climatic conditions and postharvest environment. Among the hundreds of volatiles identified compounds esters are quantitatively and qualitatively the most abundant class of these compounds. The chemical and physical properties of the different volatiles vary, and this may influence the results obtained in volatile determinations depending on the method used. Headspace and solvent extraction methods are mostly used to characterize strawberry aroma by sampling and analyzing volatile compounds. Thus, different determination methods might cause alterations in the apparent overall aroma composition, and usually only approximate quantitative determinations of the volatiles can be performed. Quality control can be difficult if inappropriate methods are used. SPME (Solid Phase Micro Extraction) is a solvent-free, inexpensive, rapid and versatile method for the extraction of organic compounds. It consists of a fused-silica fibre, coated with a polymeric stationary phase introduced into a liquid or gas sample. The aim of the present work was to compare various SPME fibres (CAR/PDMS, PDMS, CAR/PDMS/DVB) using GC/MS (Gas Chromatography Mass Spectrometry) to identify volatile compositions in fruits of the 'Rubygem' cultivar.