Helium extraction volatiles analysis

An example of a DHS application is the determination of aroma-active compounds in bambuu shoots. In this study, compoimds such as p-cresol, methional, 2-heptanoI, acetic acid, ( ,Z)-2,6-nonadienal, linalool, phenyl acetaldehyde, were extracted from the bambuu shoot samples and analysed by GC. The required sample amount was 10 g, and the extraction temperature was 60°C, using a 30 min extraction time. The stripped analytes were first trapped into a cooled adsorbent tube (VOCARB 3000, at 0 °C), and then thermally desorbed to GC. In DTD, the sample amount required for the analysis is typically smaller than in solid head-space (SHS). In the determination volatile components such as camphor, 1,8-cineoIe and 2,3,S,S-tetramethyl-4-methylene-2-cyclopenten-l-one, from Lavandula luisieri, only 10-20 mg of (dry) plant sample was required for the analysis. The volatiles were desorbed fi om the sample under a helium flow and then cryofocused on a Tenax TA trap at -30 °C. The trap was then quickly heated and the desorbed volatiles were transferred directly to the GC column through a heated fused-silica line (85). 

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