Table 1
Volatile flavor compounds identified in orange and grapefruit

No. RI1) Compound name MF2) MW3) Orange Grapefruit
Pulp Peel Pulp Peel
area% mg/kg area% mg/kg area% mg/kg area% mg/kg
1 552 2,3-Butanedione C4H6O2 86 0.34 0.41 - - - - - -
2 560 2-Butanone C4H8O 72 - - - - 1.20 2.34 0.13 5.62
3 574 Ethyl acetate C4H8O2 88 11.74 14.12 0.36 16.23 8.71 17.02 0.83 35.19
4 592 2-Methyl-1-propanol C4H10O 74 0.23 0.27 - - 0.06 0.11 - -
5 629 3-Methylbutanal C5H10O 86 0.04 0.05 - - - - - -
6 639 1-Butanol C4H10O 74 0.43 0.52 0.00 0.10 0.16 0.31 0.01 0.27
7 697 2-Pentanol C5H12O 88 0.54 0.65 0.00 0.21 0.77 1.51 0.04 1.49
8 707 Acetoin C4H8O2 88 0.47 0.57 - - 0.35 0.68 0.00 0.19
9 731 3-Methyl-1-butanol C5H12O 88 0.70 0.84 - - - - - -
10 734 2-Methyl-1-butanol C5H12O 88 0.25 0.30 - - - - - -
11 771 3-Methyl-2-buten-1-ol C5H10O 86 - - 0.00 0.10 - - - -
12 790 2,3-Butanediol C4H10O2 90 - - 0.02 0.97 - - - -
13 799 Hexanal C6H12O 100 0.76 0.92 0.09 4.22 0.02 0.04 0.04 1.71
14 833 Furfural C5H4O2 96 - - - - 0.05 0.10 - -
15 846 Ethyl2-butenoate C6H10O2 114 0.13 0.15 - - - - - -
16 853 (E)-2-Hexenal C6H10O 98 - - 0.05 2.27 0.09 0.18 0.03 1.09
17 862 3-Methyl-hexanal C7H14O 114 0.11 0.13 - - 0.12 0.23 - -
18 867 Hexanol C6H14O 102 0.01 0.01 - - 0.03 0.06 - -
19 876 3-Methylbutyl-acetate C7H14O2 130 - - - - - - 0.01 0.33
20 878 2-Methylbutyl-acetate C7H14O2 130 - - - - - - 0.03 1.31
21 889 Heptan-2-one C7H14O 114 0.01 0.01 - - - - 0.06 2.70
22 899 Heptanal C7H14O 114 1.00 1.21 - - - - 0.04 1.62
23 925 α-Thujene C10H16 136 - - 0.03 1.27 - - 2.54 107.10
24 932 α-Pinene C10H16 136 0.48 0.58 3.16 142.48 0.10 0.20 0.05 2.11
25 948 Camphene C10H16 136 0.14 0.16 0.02 1.03 0.04 0.07 - -
26 956 (E)-2-Heptenal C7H12O 112 0.01 0.01 - - - - - -
27 962 Benzaldehyde C7H6O 106 0.03 0.04 - - 0.02 0.05 1.33 56.03
28 972 Sabinene C10H16 136 0.09 0.11 1.84 82.92 0.02 0.04 3.11 131.32
29 972 β-Pinene C10H16 136 - - - - - - - -
30 983 6-Methyl-5-hepten-2-one C8H14O 126 0.00 0.00 - - 0.07 0.14 14.62 617.37
31 987 β-myrcene C10H16 136 0.77 0.93 10.89 491.02 0.26 0.50 0.50 21.25
32 1004 Octanal C8H16O 128 0.16 0.20 - - 0.05 0.09 - -
33 1008 δ-3-Carene C10H16 136 0.13 0.15 3.88 174.83 - - - -
34 1023 Carvomenthene C10H18 138 0.39 0.47 - - - - 44.29 1870.24
35 1031 Limonene C10H16 136 54.31 65.32 66.70 3008.1 53.74 105.00 - -
36 1042 (E)-2-Ethyl hexenoate C8H14O2 142 0.56 0.67 - - - - - -
37 1045 Phenylacetaldehyde C8H8O 120 1.53 1.84 - - 1.62 3.17 - -
I.S 1055 Butylbenzene C10H14 134 - - - - - - 2.04 85.97
38 1067 (E)-β-Ocimene C10H16 136 - - 0.05 2.44 0.04 0.08 0.17 7.25
39 1067 γ-Terpinene C10H16 136 0.11 0.14 0.00 0.13 - - 0.37 15.49
40 1071 Octanol C8H18O 130 0.01 0.01 0.08 3.64 - - 2.29 96.54
41 1073 (Z)-Linalool oxide C10H18O2 170 0.04 0.04 - - 5.78 11.30 - -
42 1075 (Z)-Sabinene hydrate C10H18O 154 0.03 0.04 - - - - - -
43 1079 (E)-Sabinene hydrate C10H18O 154 - - 0.03 1.49 - - 1.39 58.63
44 1087 (E)-Linalool oxide C10H18O2 170 - - - - 3.26 6.37 - -
45 1088 α-Terpinolene C10H16 136 0.31 0.37 0.59 26.39 - - 1.33 55.96
46 1098 Linalool C10H18O 154 0.37 0.44 1.80 80.96 2.18 4.26 0.86 36.24
47 1106 Nonanal C9H18O 142 4.12 4.95 0.52 23.56 4.32 8.45 0.14 6.11
48 1111 Heptyl acetate C9H18O2 158 - - - - - - -
49 1115 (E)-4,8-dimethyl-Nona-1,3,7-triene C11H18 150 - - 0.05 2.13 - -
50 1116 1,3,8-ρ-Menthatriene C10H14 134 - - 0.03 1.27 - - 0.09 3.65
51 1122 (E)-p-Mentha-2,8-dienol C10H16O 152 0.16 0.19 0.04 1.73 0.08 0.17 0.10 4.12
52 1126 Ethyl3-hydroxyhexanoate C8H16O3 160 1.10 1.32 - - - - - -
53 1129 (Z)-p-Menth-2-en-1-ol C10H18O 154 - - 0.01 0.62 0.04 0.08 0.02 0.81
54 1131 Limona ketone C9H14O 138 0.20 0.24 - - 0.05 0.09 - -
55 1133 (Z)-Limonene oxide C10H16O 152 0.13 0.16 0.38 16.93 0.09 0.19 0.28 11.62
56 1138 (E)-Limonene oxide C10H16O 152 0.25 0.30 0.42 19.10 0.03 0.07 0.57 23.91
57 1150 Camphor C10H16O 152 1.03 1.24 - - 0.23 0.44 - -
58 1153 Citronellal C10H18O 154 - - 0.40 18.20 - - 0.94 39.83
59 1162 (E)-2-Nonenal C9H16O 140 0.09 0.11 - - - - - -
60 1169 (E)-β-Terpineol C10H18O 154 0.29 0.35 0.07 3.07 0.06 0.12 0.09 3.64
61 1171 (Z)-Linalool oxide(pyranoid) C10H18O2 170 - - - - 0.06 0.12 0.07 3.04
62 1172 1-Nonanol C9H20O 144 - - 0.01 0.42 - - - -
63 1174 Borneol C10H18O 154 0.09 0.11 0.02 0.81 - - - -
64 1175 (E)-Linalool oxide(pyranoid) C10H18O2 170 - - - - 0.07 0.13 0.08 3.58
65 1181 4-Terpineol C10H18O 154 0.01 0.01 0.22 9.83 0.02 0.05 0.34 14.53
66 1194 Ethyl octanoate C10H20O2 172 0.17 0.20 - - - - 0.04 1.81
67 1196 α-Terpineol C10H18O 154 0.61 0.73 0.75 33.66 0.24 0.46 0.86 36.16
68 1206 Decanal C10H20O 156 0.11 0.13 1.16 52.32 0.05 0.10 0.99 41.71
69 1208 Octyl acetate C10H18O2 172 - - - - 0.05 0.10 2.65 111.94
70 1219 (E)-Carveol C10H16O 152 0.36 0.44 0.15 6.92 0.11 0.22 0.31 13.26
71 1224 Nerol C10H18O 154 0.01 0.02 0.15 6.83 - - - -
72 1225 Citronellol C10H20O 156 - - 0.09 4.26 - - 0.13 5.68
73 1233 (Z)-Carveol C10H16O 152 0.07 0.09 0.03 1.17 - - 0.04 1.86
74 1238 Neral C10H16O 152 0.02 0.02 0.37 16.73 0.02 0.04 0.23 9.74
75 1245 Carvone C10H14O 150 0.20 0.24 0.07 3.12 0.02 0.04 0.08 3.35
76 1249 Geraniol C10H18O 154 - - 0.13 6.03 0.76 1.49 0.06 2.63
77 1252 Butyrophenone C10H12O 148 0.06 0.07 - - 0.14 0.28 0.02 0.87
78 1256 Piperitone C10H16O 152 - - 0.01 0.25 - - - -
79 1261 (E)-2-Decenal C10H18O 154 - - 0.02 0.71 - - 0.02 0.65
80 1267 Geranial C10H16O 152 - - 0.42 18.94 0.05 0.10 0.30 12.68
81 1271 Isopiperitenone C10H14O 150 - - 0.05 2.25 - - - -
82 1271 Decanol C10H22O 158 - - - - - - 0.06 2.51
83 1277 Perillaldehyde C10H14O 150 0.05 0.06 0.11 4.80 0.02 0.04 0.19 8.21
84 1291 Limonen-10-ol C10H16O 152 0.11 0.13 0.08 3.70 - - 0.04 1.79
85 1299 Perilla alcohol C10H16O 152 0.20 0.24 0.05 2.36 0.27 0.52 0.12 5.13
86 1306 Undecanal C11H22O 170 0.10 0.12 0.26 11.66 0.04 0.08 0.48 20.29
87 1309 4-Vinyl-guaiacol C9H10O2 150 - - - - 0.09 0.17 - -
88 1317 (E,E)-2,4-Decadienal C10H16O 152 - - 0.03 1.39 - - 0.01 0.22
89 1321 Methyldecanoate C11H22O2 186 - - 0.02 0.99 - - - -
90 1331 (E)-Carvyl acetate C12H18O2 194 - - 0.01 0.51 - - 0.14 6.12
91 1347 Citronellyl acetate C12H22O2 198 - - 0.05 2.39 - - - -
92 1347 α-Terpinyl acetate C12H20O2 196 - - - - 0.06 0.11 0.40 16.93
93 1349 (Z)-Carvyl acetate C12H18O2 194 - - 0.00 0.22 - - 0.06 2.71
94 1353 Neryl acetate C12H20O2 196 0.02 0.02 0.05 2.46 0.11 0.21 0.17 7.34
95 1359 Decanoic acid C10H20O2 172 - - 0.05 2.36 - - 0.06 2.58
96 1375 Geranyl acetate C12H20O2 196 0.01 0.01 0.06 2.57 0.02 0.04 0.88 37.25
97 1378 α-Copaene C15H24 204 0.02 0.02 0.15 6.65 0.15 0.29 0.73 30.80
98 1384 β-Elemene C15H24 204 - - 0.18 7.96 0.08 0.16 0.02 0.88
99 1387 Octyl butyrate C12H24O2 200 - - - - - - 0.00 0.10
100 1391 β-Cubebene C15H24 204 - - - - - - 0.74 31.04
101 1392 Ethyl decanoate C12H24O2 200 0.18 0.21 - - - - - -
102 1406 Decyl acetate C12H24O2 200 - - - - 0.05 0.09 0.16 6.87
103 1408 Dodecanal C12H24O 184 - - 0.24 11.04 - - 0.34 14.19
104 1408 (Z)-Caryophyllene C15H24 204 0.06 0.08 - - 0.43 0.85 - -
105 1419 ρ-Menth-1-en-9-ol acetate C12H20O2 196 - - 0.00 0.09 - - 0.01 0.41
106 1424 (E)-Caryophyllene C15H24 204 0.07 0.09 0.13 5.93 7.86 15.36 2.04 85.98
107 1432 Perillyl acetate C12H18O2 194 0.02 0.03 - - 0.03 0.05 0.10 4.02
108 1434 β-Copaene C15H24 204 - - 0.09 4.24 - - - -
109 1437 Aromadendrene C15H24 204 - - 0.01 0.49 - - - -
110 1438 α-Guaiene C15H24 204 - - - - - - 0.04 1.71
111 1446 Geranylacetone C13H22O 194 - - - - 0.05 0.09 - -
112 1451 (E)-β-Farnesene C15H24 204 - - 0.05 2.11 - - 0.11 4.63
113 1451 α-Humulene C15H24 204 0.15 0.18 0.03 1.57 0.66 1.28 0.30 12.72
114 1454 Sesquisabinene C15H24 204 - - - - - - 0.03 1.17
115 1466 (E)-2-Dodecenal C12H22O 182 - - - - - - 0.02 0.83
116 1477 γ-Muurolene C15H24 204 - - 0.01 0.64 - - 0.03 1.13
117 1485 GermacreneD C15H24 204 - - 0.09 4.04 - - 0.42 17.56
118 1488 Selina-4,11-diene C15H24 204 0.44 0.53 0.04 1.67 0.05 0.10 0.08 3.46
119 1497 Valencene C15H24 204 7.61 9.15 0.78 35.18 0.05 0.10 0.32 13.44
120 1500 α-Selinene C15H24 204 0.43 0.52 - - - - - -
121 1500 Bicyclogermacrene C15H24 204 - - - - 0.03 0.06 0.32 13.63
122 1502 (E,E)-α-Farnesene C15H24 204 - - 0.03 1.47 - - - -
123 1505 δ-Guaiene C15H24 204 - - 0.00 0.09 - - 0.03 1.34
124 1507 α-Bulnesene C15H24 204 0.12 0.15 0.01 0.45 - - 0.02 0.92
125 1510 Tridecanal C13H26O 198 - - - - 0.14 0.27 0.00 0.12
126 1520 δ-Cadinene C15H24 204 0.03 0.03 0.18 7.90 0.15 0.29 0.85 36.09
127 1524 7-Epi-α-selinene C15H24 204 0.49 0.59 0.04 1.92 0.03 0.06 0.12 5.08
128 1529 Nerylbutyrate C14H24O2 224 - - 0.00 0.13 - - - -
129 1550 α-Elemol C15H26O 222 - - 0.05 2.46 - - 0.31 13.20
130 1555 Dodecanoi cacid C12H24O2 200 - - 0.01 0.32 - - 0.01 0.63
131 1560 (E)-Nerolidol C15H26O 222 - - 0.01 0.24 0.06 0.12 0.09 3.88
132 1581 Spathulenol C15H24O 220 - - 0.02 0.68 0.04 0.09 0.08 3.51
133 1588 Caryophyllene oxide C15H24O 220 0.03 0.03 0.05 2.10 1.85 3.61 0.09 3.77
134 1590 Ethyl dodecanoate C14H28O2 228 0.08 0.10 - - - - 0.01 0.58
135 1604 Dodecyl acetate C14H28O2 228 - - - - 0.04 0.07 0.01 0.40
136 1611 Tetradecanal C14H28O 212 0.01 0.01 0.01 0.51 - - 0.04 1.58
137 1615 Humulene epoxide II C15H24O 220 0.04 0.05 0.01 0.36 0.16 0.30 0.02 0.68
138 1636 γ-Eudesmol C15H26O 222 - - 0.01 0.34 - - 0.04 1.50
139 1648 T-Muurolol C15H26O 222 - - 0.01 0.35 - - 0.04 1.58
140 1650 α-Muurolol C15H26O 222 - - 0.00 0.15 - - - -
141 1659 Valerianol C15H26O 222 0.11 0.13 - - - - - -
142 1659 T-Cadinol C15H26O 222 - - 0.02 0.85 - - 0.05 2.07
143 1664 Neo-intermedeol C15H26O 222 0.02 0.02 0.01 0.32 - - 0.03 1.29
144 1671 Intermedeol C15H26O 222 0.04 0.05 0.02 1.04 0.14 0.28 0.34 14.36
145 1693 β-Sinensal C15H22O 218 0.00 0.00 0.07 3.18 - - 0.09 3.69
146 1713 Pentadecanal C15H30O 226 0.06 0.07 - - 0.03 0.06 - -
147 1714 (E,E)-Farnesol C15H24O 220 - - 0.08 3.44 - - 0.05 2.00
148 1718 Nootkatol C15H24O 220 - - - - - - 0.05 2.12
149 1736 (E,E)-Farnesal C15H24O 220 - - 0.00 0.16 0.03 0.06 0.02 0.69
150 1749 α-Sinensal C15H22O 218 - - 0.11 5.11 - - 0.05 2.01
151 1756 Tetradecanoic acid C14H28O2 228 - - - - - - 0.00 0.18
152 1775 Octyl octanoate C16H32O2 256 - - - - - - 0.00 0.16
153 1789 Ethyl myristate C16H32O2 256 0.03 0.04 - - - - - -
154 1809 Nootkatone C15H22O 218 0.68 0.82 0.17 7.50 0.58 1.14 2.46 103.94
155 1814 Hexadecanal C16H32O 240 0.01 0.01 0.04 1.70 0.03 0.05 0.15 6.36
156 1830 Farnesyl acetate C17H28O2 264 - - - - - - 0.02 0.75
157 1854 Pentadecanoic acid C15H30O2 242 - - 0.00 0.17 - - 0.02 0.66
158 1901 Methyl palmitoleate C17H32O2 268 - - 0.01 0.43 - - 0.03 1.47
159 1908 Farnesyl acetone C18H30O 262 0.01 0.01 0.01 0.34 0.10 0.19 0.04 1.75
160 1922 Methyl palmitate C17H34O2 270 0.04 0.05 0.01 0.29 - - 0.03 1.09
161 1957 Palmitic acid C16H32O2 265 1.85 2.23 0.43 19.52 0.76 1.48 0.87 36.89
162 1989 Ethyl palmitate C18H36O2 284 0.26 0.32 0.02 0.68 0.10 0.19 0.10 4.12
163 2020 Octadecanal C18H36O 268 - - 0.02 0.83 0.03 0.06 0.08 3.28
164 2089 Methyl linoleate C19H34O2 294 0.02 0.03 0.02 0.86 - - 0.06 2.36
165 2097 Methyl linolenate C19H32O2 292 0.11 0.14 0.01 0.26 0.11 0.21 0.02 0.99
166 2101 Methyl oleate C19H36O2 296 0.04 0.05 0.00 0.17 - - 0.02 0.74
167 2129 Linoleic acid C18H32O2 280 0.08 0.10 0.22 10.01 0.03 0.06 0.21 8.98
168 2135 Oleic acid C18H34O2 282 0.37 0.44 0.34 15.39 0.04 0.09 0.31 12.89
169 2156 Ethyl linoleate C20H36O2 308 0.26 0.32 0.02 1.10 0.14 0.28 0.10 4.24
170 2162 Ethyl linolenate C20H34O2 306 0.45 0.54 0.01 0.56 0.14 0.27 0.06 2.62
171 2169 Ethyl oleate C20H38O2 310 0.24 0.28 0.02 1.02 0.10 0.19 0.03 1.24
Total 100 120.55 100 4510.81 100 195.60 100 4223.68
1)Retention index; 2)Molecular formula; 3)Molecular weight.