Characterisation of volatile compounds of blueberry fruit by headspace– solid phase microextraction combined with gas chromatography

Volatile compounds of mature fruits in blueberry (Vaccinium corymbosum L.) cultivars Duke, Elliot, Sierra and Bluecrop, during successive three harvesting period were examined. The volatile compounds were extracted using headspace-solid-phase microextraction (HS-SPME) and then analyzed using capillary gas chromatography. A total of twenty one volatile compounds were identified by HS-SPME, including higher alcohols, esters, aldehydes, phenols, monoterpens and acids, among which esters and alcohols were found to be the major compounds in all investigated cultivars. On the basis of the relative amounts of identified volatile compounds, it is believed that the following compounds probably contributed to the fresh blueberry odor: 2-phenylethyl acetate,  -terpineol, 1-octanol, isoamyl alcohol, ethyl acetate, hexyl acetate, nerol. The approximate concentrations of the identified volatile compounds are tabulated. The major compounds in all blueberry cultivars were ester (2-phenylethyl acetate) and alcohol (1-octanol) during all three harvesting periods. Statistical analysis (ANOVA) showed that cultivar significantly influenced on levels of 2-phenyl ethanol and geraniol (p≤ 0, 05) while harvesting period significantly influenced on level of isoamyl alcohol (p≤ 0, 05), and on level of isoamyl acetate (p≤ 0, 01).