Submitted to: Proceedings of Florida State Horticultural Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/19/2008
Publication Date: 4/1/2009
Citation: Jouquand, C., Chandler, C., Goodner, K., Plotto, A. 2008. Optimization of strawberry volatile sampling by direct gas chromatography olfactometry. Proceedings of Florida State Horticultural Society. 121:260-264.
Interpretive Summary: When doing flavor research, there is no perfect way of extracting samples for analyzing aroma volatiles. This paper presents a simple method to choose the sample extract with the odor profile closest to the sample. This method can be used by flavor chemists optimize their sample extract before analysis by gas chromatography.
Technical Abstract: The aim of this work was to choose a suitable sampling headspace technique to study ‘Festival’ aroma, the main strawberry cultivar grown in Florida. For that, the aromatic quality of extracts from different headspace techniques was evaluated using direct gas chromatography-olfactometry (D-GC-O), a special tool which is dedicated to assessing global odor from solvent-free extracts. A gas chromatography equipped with a sniffing port was equipped with a 15-cm deactivated silica column, thus allowing evaluation of global odor of headspace extracts without chromatographic separation. Two SPME extracts, with different types of fiber (PDMS/DVB fiber and DVD/Car/PDMS fiber), and two static headspace extracts, with different phase ratios (ratio of gas and sample phase volumes), from 'Festival' puree were evaluated using D-GC-O. A similarity test with three panelists allowed comparison of the odor of these extracts to that of 'Festival' puree. The results indicated that SPME extracts with a DVD/Car/PDMS fiber generated the most representative odor with a "green" impression and a strong "fruity" note. A fruity note was also obtained with static headspace extracts which exhibited the highest volatile concentration in headspace, i.e the lowest phase ratio. When comparing the aroma profile of each extract, the "DVD/Car/PDMS" extract showed the highest concentration of methyl butanoate and ethyl butanoate, two key compounds in strawberry aroma.