title: Solid phase microextraction-gas chromatography for quantifying headspace hexanal above freeze-dried chicken myofibrils.
abstract: A method using solid phase microextraction (SPME) combined with gas chromatography/mass spectrometry (GC/MS) was developed and used to determine the oxidation of freeze-dried chicken myofibrils spiked with methyl linoleate. Freeze-dried chicken myofibrils were found to act as a significant reservoir for hexanal. Recovery of hexanal emissions from the headspace above spiked myofibrils was 95% using a 5 min sampling time, with a total analysis time of approximately 12 min/sample. The SPME-GC/MS working linear response was from 0.01 to 10 mg hexanal/L (r( 2) = 0.995). Freeze-dried chicken myofibrils with added methyl linoleate (0.6 mmol/g of protein) were stored at 50 degrees C at water activities of 0.30 and 0.75 for 0, 12, 27, and 50 h. Lipid oxidation was determined using SPME-GC/MS to measure headspace hexanal concentration, the thiobarbituric acid reactive substances assay (TBARS) to quantify malonaldehyde, and a conjugated diene assay. Lipid oxidation was influenced by storage time and water activity. A strong correlation (r = 0.938) existed between SPME-GC/MS and TBARS. The use of SPME-GC/MS was a sensitive and rapid method for detecting hexanal as an indicator of lipid oxidation in chicken myofibrils.
authors.affiliation: Department of Food Science and Human Nutrition, Michigan State University, East Lansing, Michigan 48824, USA. cgoodrid@scimail.uwarterloo.ca
authors.forename: Carolyn F
authors.initials: CF
authors.lastname: Goodridge
authors.forename: Randolph M
authors.initials: RM
authors.lastname: Beaudry
authors.forename: James J
authors.initials: JJ
authors.lastname: Pestka
authors.forename: Denise M
authors.initials: DM
authors.lastname: Smith
mesh_terms: D000447:Aldehydes / Q000032:analysis*; D000818:Animals; D002645:Chickens; D002849:Chromatography, Gas / Q000379:methods*; D005612:Freeze Drying; D008401:Gas Chromatography-Mass Spectrometry; D008041:Linoleic Acids / Q000008:administration & dosage; D015227:Lipid Peroxidation; D009210:Myofibrils / Q000737:chemistry*; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis
chemical_list: D000447:Aldehydes; D008041:Linoleic Acids; D017392:Thiobarbituric Acid Reactive Substances; C005575:methyl linoleate; C010463:n-hexanal