Determination of 3-alkyl-2-methoxypyrazines in lady beetle-infested wine by solid-phase microextraction headspace sampling.
This study determined the concentration of 3-alkyl-2-methoxypyrazines in Frontenac and Leon Millot wines made from grapes that were naturally or artificially infested with the multicolored Asian lady beetle, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae). Headspace sampling with solid-phase microextraction (SPME) and gas chromatography (GC) was used for the quantification of 3-isopropyl-2-methoxypyrazine (IPMP), 3- sec-butyl-2-methoxypyrazine (SBMP), and 3-isobutyl-2-methoxypyrazine (IBMP). The resulting method parameters included linearity (r2 > 0.98), limit of detection (>0.25 ng/L), relative standard deviation (<20%), and recovery (75-125%). IPMP concentrations in wine were not significantly different among the levels of natural or artificial infestations of H. axyridis. SBMP was found only in wine artificially infested with H. axyridis. IBMP was found in wine artificially infested with H. axyridis and in Frontenac wine, but not in Leon Millot. The consequences of these results for future research in the contamination of wine with H. axyridis are discussed.
Galvan
Tederson Luiz
TL
Department of Entomology, 219 Hodson Hall, 1980 Folwell Avenue, University of Minnesota, St. Paul, Minnesota 55108, USA. galva008@umn.edu
Kells
Stephen
S
Hutchison
William Dale
WD
D000818:Animals; D002849:Chromatography, Gas; D001517:Coleoptera / Q000378:metabolism*; D005506:Food Contamination / Q000032:analysis*; D005638:Fruit / Q000737:chemistry*; D011719:Pyrazines / Q000032:analysis*; D027843:Vitis / Q000737:chemistry*; D014920:Wine / Q000032:analysis*
D011719:Pyrazines