Volatile Organic Composition in Blueberry


Overton, Santford V and Manura, John J.

Volatile and semi-volatile organic compounds present both in the sample matrix and in the headspace aroma exhibit a tremendous influence on the flavor/fragrance qualities of blueberries. There is a concern in the blueberry industry as to what constitutes the optimum conditions for harvesting blueberries so as to provide a consistent quality and flavor of blueberry to the consumer. Several investigations have reported that the concentrations of volatile constituents increased with the maturation of blueberries. The major volatiles of blueberries appear to be useful indices for determining maturity, and recently, the determination of flavor precursors and intermediates have become the target of flavor studies. To date, headspace GC analysis, cryofocusing techniques, and high resolution GC have been used for the analysis of blueberry volatiles from promising cultivars under development. However, static headspace techniques are limited in their detection and identification of many organic volatiles and especially the semi-volatile organics. Other techniques are needed to profile a wider range of volatile and semi-volatile organics in blueberries and to identify the flavors, fragrances, off-flavors, off-odors and potential contaminants that may be present. The purpose of this investigation is to develop an analytical technique that could detect and identify a wide range of volatile and semi-volatile organic compounds in blueberry. For this study, volatile organic compounds are purged from blueberry samples followed by trapping on Tenax® TA adsorbent resin using a dynamic purge and trap technique (P&T). The adsorbent traps are subsequently analyzed by thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS). The P&T technique permits the analysis of a wider range of both volatile and semi-volatile organic compounds and is more sensitive as compared to the static headspace technique.

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