Effect of oleic and linoleic acids on the production of deep-fried odor in heated triolein and trilinolein.
To determine sources of desirable deep-fried flavor in frying oils, degradation products from heated triolein and trilinolein with 5-31% polar compounds representing low to high deterioration were evaluated by purge-trap gas chromatography-mass spectrometry-olfactometry. (E,E)-2,4-Decadienal, 2-heptenal, 2-octenal, 2,4-nonadienal, and 2,4-octadienal produced deep-fried odor at moderate-strong intensities in heated trilinolein. However, unexpected aldehydes-2,4-decadienal, 2,4-undecadienal, 2,4-nonadienal, and 2-octenal (all <15 ppm)-were produced in triolein heated for 6 h. These dienals possibly were produced by hydroperoxidation and/or hydroxylation followed by dehydration of 2-alkenals. The 2-alkenals were produced from thermal decomposition of hydroperoxides, epoxides, and keto and dimeric compounds produced during the heating of triolein. These aldehydes produced low intensities of deep-fried odor in triolein. This information helps to explain sources of the deep-fried flavor that is characteristic of high linoleic frying oils but which is only at low intensity levels in high oleic frying oils.
Warner
K
K
Food Quality and Safety Research and Bioactive Active Constituents Research, ARS/NCAUR, U.S. Department of Agriculture, Peoria, Illinois 61604, USA. warnerk@mail.ncaur.usda.gov
Neff
W E
WE
Byrdwell
W C
WC
Gardner
H W
HW
D002851:Chromatography, High Pressure Liquid / Q000379:methods; D003296:Cooking; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D006358:Hot Temperature; D006801:Humans; D019787:Linoleic Acid / Q000737:chemistry*; D009812:Odorants; D019301:Oleic Acid / Q000737:chemistry*; D013649:Taste; D014280:Triglycerides / Q000737:chemistry*; D014304:Triolein / Q000737:chemistry*; D014835:Volatilization
D014280:Triglycerides; D014304:Triolein; D019301:Oleic Acid; D019787:Linoleic Acid; C009564:trilinolein