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The volatile fraction of murici, bacuri and sapodilla are here studied because of their increasing interest for consumers, abundance of production in Brazil, and the general demand for new flavors and aromas. Their volatile profiles were studied by two High Concentration Capacity Headspace techniques (HCC-HS), Headspace Solid Phase Microextraction (HS-SPME) and Headspace Sorptive Extraction (HSSE), in combination with GC-MS. Murici volatile fraction mainly contains esters (38%), carboxylic acids (19%), aldehydes (11%), alcohols (14%), others (13%) and sulfur compounds; bacuri is characterized by terpenes (41%), non-terpenic alcohols (24%), esters (15%), aldehydes (6%), and others (12%); sapodilla consists of esters (33%), alcohols (27%), terpenes (18%) and others (21%). The GC-MS component co-elution was overcome by GC×GC-qMS. The adoption of modern analysis technologies afforded to achieve a better knowledge of the volatile fraction composition of these fruit pulps by increasing substantially the number of compounds identified.

The definitive version is available at: La versione definitiva è disponibile alla URL: [http://link.springer.com/article/10.1007/s00216-011-5600-4#page AbstractHeadspace solid-phase microextraction (HS-SPME) comprehensive two-dimensional (2D) gas chromatography combined with quadrupole-mass spectrometry (GCxGC-qMS) with dedicated comparative data elaboration was applied to separate chemical patterns arising from the interaction between some Mentha species and the herbivore Chrysolina herbacea, also known as the mint bug.Upon feeding on different Mentha species (M. spicata L., M. x piperita L. and M. longifolia L.), C. herbacea produced frass (faeces) which were characterized by a typical volatile fraction. HS-SPME GCxGC-qMS analysis of the complex volatile fraction of both mint leaf and C. herbacea frass was submitted to advanced fingerprinting analysis of 2D chromatographic data. 1,8-Cineole, found in the leaves of all the Mentha species examined, was oxidized and C. herbacea frass yielded high rates of several hydroxy-1,8-cineoles, including 2α-hydroxy-, 3α-hydroxy-, 3β-hydroxy-and 9-hydroxy-1,8-cineole. Upon insect feeding, several unknown oxidized monoterpenes, a p-menthane diol and three unknown phenylpropanoids were also detected in the frass volatiles. In M. longifolia, the occurrence of the monoterpene piperitenone oxide was found to be toxic and associated with insect death. The results of this work show that high throughput techniques such as HS-SPME and GCxGC-qMS fingerprint analysis are ideal tools to analyze complex volatile matrices, and provide a sensitive method for the direct comparison and chemical visualization of plant and insect emitted volatile components.

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