Table 2. Compounds identified in the fresh duck egg and salted duck egg yolk control at 28 d of salting analyzed by SPME GC-MS

Compounds classes Groups Peak no RT (min) Compounds names
Ester Fresh egg 1 17.87 Succinic acid, decyl tetrahydrofur furyl ester
2 22.71 l-Alanine, N-valeryl-, tetradecyl ester
Acid Fresh egg 1 7.95 Styrene
2 22.25 2-Thiophenecarboxylic acid, 5-(1,1-dimethylethoxy)-
3 25.12 Propanedioic acid, propyl-
4 36.94 Octadec-9-enoic acid
5 44.51 n-Hexadecanoic acid
Control 1 15.97 Acetic acid
2 21.48 4-(Methylamino)butyric acid
3 33.83 Pterin-6-carboxylic acid
4 36.93 6-Octadecenoic acid
5 44.51 n-Hexadecanoic acid
Alcohol Control 1 3.99 Ethanol
2 7.14 1-Propanol, 2-methyl-
3 10.10 1-Butanol, 3-methyl-
4 19.75 3,4-Dimethylcyclohexanol
Alkane Fresh egg 1 25.63 3-Azabicyclo[3.2.2]nonane
2 29.48 2-Methylaminomethyl-1,3-dioxolane
3 40.92 1,4,7,10,13,16-Hexaoxacyclooctadecane
Control 1 30.79 2-Methylaminomethyl-1,3-dioxolane
2 31.01 3-Azabicyclo[3.2.2]nonane
3 35.19 1,3-Dioxolane, 4-methyl-
4 36.48 1,4,7,10,13,16-Hexaoxacyclooctadecane
Ketone Fresh egg 1 ND ND
Control 1 11.71 Acetoin
2 14.51 2-Nonanone
Aldehyde Fresh egg 1 13.65 Nonanal
Control 1 9.10 Butanal, 3-methyl-
2 14.63 Nonanal
3 17.77 Benzaldehyde
Nitrogen Fresh egg 1 16.85 Cyanoacetylurea
2 20.39 Methylpent-4-enylamine
3 23.12 Butanamine, 2,2-dinitro-N-methyl
4 24.38 Propanamide
5 27.36 Ethylamine, 2-(adamantan-1-yl)-1-m-ethyl
6 28.98 N-Formyl-dl-alanine
7 31.00 p-Hydroxyamphetamine
8 31.80 Ethyl oxamate
Control 1 20.22 N-Acetylnorephedrine
2 35.34 Dimethylamine
Ether Fresh egg 1 41.18 Octaethylene glycol monododecyl eter
2 43.82 15-Crown-5
Control 1 38.33 Octaethylene glycol monododecyl eter
2 41.58 15-Crown-5
3 44.01 3,6,9,12-Tetraoxatetradecan-1-ol
Others Fresh egg 1 8.70 Methallyl cyanide
2 15.49 1-Butene, 4-isothiocyanato-
Control 1 22.85 Naphthalene
SPME GC-MS, solid phase microextraction - gas chromatography - mass spectrometry; ND, not detected.