Table 1. Relative levels (fold changes) of VOCs detected in juices of four Citrus varieties.
| Code | Cluster | Volatile Organic Compound | Family Code/Number | Retention Time (min) | Specific Ion (m/z) | Chandler | Clemenules | Fortune | Powell |
| 1 | A1 | 2-carene | Mt hd/1 | 24.05 | 93 | 1±0.25 | - | traces | traces |
| 2 | A1 | (Z)-linalool oxidea , b | Alc/1 | 26.47 | 111 | 1±0.24 | - | traces | - |
| 3 | A1 | (E)-linalool oxidea , b | Alc/2 | 27.00 | 111 | 1±0.22 | - | - | - |
| 4 | A1 | (E,E)-2,4-nonadienal | Ald/1 | 31.10 | 81 | 1±0.31 | - | - | - |
| 5 | A1 | (Z)-ocimene | Mt hd/2 | 24.87 | 93 | 1±0.61 | - | - | - |
| 6 | A1 | p-cymene | Mt hd/3 | 24.91 | 119 | 1±0.85 | - | - | - |
| 7 | A1 | β-caryophyllene | Sqt/1 | 37.87 | 133 | 1±0.57 | - | - | traces |
| 8 | A1 | nootkatonec | Ket/1 | 47.87 | 121 | 1±0.33b | - | 0.02±0.01a | 0.02±0.01a |
| 9 | A1 | α-humulene | Sqt/2 | 38.82 | 80 | 1±0.64b | traces | 0.04±0.01a | 0.03±0.01a |
| 10 | A1 | β-pinene | Mt hd/4 | 23.46 | 93 | 1±0.88b | 0.11±0.01a | 0.17±0.03a | 0.21±0.12a |
| 11 | A1 | 1-pentanol | Alc/3 | 14.60 | 42 | 1±0.48b | 0.26±0.13a | 0.11±0.02a | 0.20±0.11a |
| 12 | A1 | 1-hexanol | Alc/4 | 18.55 | 56 | 1±0.70b | 0.12±0.02a | 0.22±0.18a | 0.87±0.32b |
| 13 | A1 | methyl hexanoate | Est/1 | 20.68 | 74 | 1± 0.46c | - | 0.07±0.02a | 0.44±0.20b |
| 14 | A1 | pseudocumene* | Ar/1 | 23.85 | 105 | 1±0.18b | 0.35±0.21a | 0.24±0.01a | 1.11±0.43b |
| 15 | A1 | ethyl hexanoate | Est/2 | 23.37 | 88 | 1±0.66b | 0.17±0.06a | 0.62±0.11ab | 2.47±1.57c |
| 16 | A2 | (E,E)-2,4-decadienal | Ald/2 | 34.17 | 81 | 1±0.68c | 0.91±0.76bc | 0.24±0.08ab | 0.05±0.02a |
| 17 | A2 | 6-methyl-5-hepten-2-oned | Ket/2 | 23.03 | 108 | 1±0.40b | 0.46±0.05a | 0.12±0.02a | - |
| 18 | A2 | octanal | Ald/3 | 23.77 | 57 | 1±0.22c | 0.83±0.19b | 0.39±0.05a | 0.22±0.06a |
| 19 | A2 | heptanal | Ald/4 | 20.00 | 70 | 1±0.26c | 0.53±0.04b | 0.42±0.01b | 0.08±0.06a |
| 20 | A2 | nonanal | Ald/5 | 27.30 | 57 | 1±0.15c | 0.71±0.15b | 0.60±0.06b | 0.15±0.27a |
| 21 | A2 | 2,3-pentanedione | Ket/3 | 11.91 | 100 | 1±0.28d | 0.79±0.15c | 0.53±0.16b | 0.07±0.04a |
| 22 | A2 | (E)-2-octenal | Ald/6 | 25.79 | 70 | 1±0.24c | 0.67±0.37b | 0.51±0.15b | 0.13±0.08a |
| 23 | A2 | (E)-2-nonenal | Ald/7 | 29.21 | 70 | 1±0.28b | 1.07±0.09b | 0.98±0.20b | 0.18±0.09a |
| 24 | A2 | (E)-2-heptenal | Ald/8 | 22.14 | 83 | 1±0.26b | 0.29±0.12a | 0.23±0.05a | 0.08±0.04a |
| 25 | A2 | 1-octen-3-one | Ket/4 | 22.82 | 70 | 1±0.46b | 0.15±0.09a | 0.19±0.07a | 0.10±0.05a |
| 26 | A2 | 1-octen-3-ol | Alc/5 | 22.85 | 57 | 1±0.32b | 0.11±0.02a | 0.14±0.03a | 0.08±0.04a |
| 27 | A2 | hexanal | Ald/9 | 16.01 | 56 | 1±0.22b | 0.22±0.03a | 0.23±0.02a | 0.14±0.07a |
| 28 | A2 | pentanal | Ald/10 | 12.04 | 58 | 1±0.24b | 0.19±0.02a | 0.23±0.04a | 0.14±0.09a |
| 29 | A2 | 2-pentylfuran | Fur/1 | 23.36 | 138 | 1±0.19b | 0.27±0.01a | 0.29±0.05a | 0.14±0.12a |
| 30 | A2 | 1-heptanol | Alc/6 | 22.39 | 70 | 1±0.55b | 0.38±0.08a | 0.58±0.32a | 0.31±0.05a |
| 31 | A2 | α-copaene | Sqt/3 | 36.41 | 119 | 1±0.58b | 0.22±0.05a | 0.55±0.06a | 0.35±0.02a |
| 32 | A2 | valencene | Sqt/4 | 39.69 | 133 | 1±0.56b | 0.15±0.02a | 1.16±0.32b | 0.91±0.17b |
| 33 | A2 | bornyl acetatea | Est/3 | 33.48 | 121 | 1±0.87a | 0.46±0.18a | 0.73±0.13a | 0.50±0.27a |
| 34 | A2 | ethyl heptanoate | Est/4 | 26.82 | 88 | 1±0.67b | 0.36±0.18a | 1.76±0.31c | 0.69±0.29ab |
| 35 | A2 | propyl acetatee * | Est/5 | 12.52 | 61 | - | - | 1±0.53 | - |
| 36 | B | 2-ethylfuran | Fur/2 | 12.17 | 81 | 1±0.21b | 2.41±0.32d | 1.22±0.24c | 0.26±0.08a |
| 37 | B | 2-methylfuran | Fur/3 | 8.84 | 82 | 1±0.25b | 1.62±0.20c | 1.13±0.29b | 0.40±0.09a |
| 38 | B | (E)-2-pentenal | Ald/11 | 14.30 | 83 | 1±0.45b | 4.09±0.80c | 1.45±0.25b | 0.41±0.07a |
| 39 | B | 1-penten-3-one | Ket/5 | 11.57 | 55 | 1±0.52a | 9.49±2.20c | 2.45±0.59b | 0.53±0.11a |
| 40 | B | ethyl propanoate | Est/6 | 12.47 | 57 | 1±1.08a | 20.09±3.13b | 22.36±7.40b | - |
| 41 | B | ethyl 2-methylbutanoatef | Est/7 | 17.87 | 102 | - | 1±0.38b | 0.16±0.04a | - |
| 42 | B | 3-pentanone* | Ket/6 | 11.97 | 57 | 1±0.63b | 2.55±0.57c | 0.59±0.19ab | 0.40±0.14a |
| 43 | B | 1-penten-3-ol | Alc/7 | 11.46 | 57 | 1±0.64a | 2.05±1.38b | 0.54±0.14a | 0.71±0.37a |
| 44 | B | β-citronellala,f f | Ald/12 | 28.92 | 69 | - | 1±1.53 | - | - |
| 45 | B | eucalyptol (1,8-cineole) | Mt cyc ether/1 | 25.38 | 154 | 1±0.62a | 6.56±1.71c | 0.30±0.06a | 2.79±1.07b |
| 46 | B | decanal | Ald/13 | 30.59 | 57 | 1±0.19a | 4.51±1.67b | 0.78±0.22a | 1.46±1.24a |
| 47 | B | (Z)-3-hexenal | Ald/14 | 15.92 | 69 | 1±0.89ab | 1.54±0.32b | 0.44±0.14a | 0.81±0.54ab |
| 48 | B | (E)-2-hexenal | Ald/15 | 18.17 | 83 | 1±0.70a | 3.92±0.81c | 1.02±0.16ab | 1.68±0.83b |
| 49 | B | geranylacetoned | Ket/7 | 37.62 | 43 | 1±0.26b | 4.73±0.36d | 0.58±0.14a | 1.65±0.67c |
| 50 | B | β-cyclocitrald | Ald/16 | 31.63 | 137 | 1±0.42a | 6.45±0.60b | 0.78±0.13a | 0.92±0.12a |
| 51 | B | β-iononed | Ket/8 | 38.90 | 177 | 1±0.44a | 11.34±0.76c | 0.88±0.18a | 1.53±0.24b |
| 52 | C1 | nerola | Alc/8 | 31.28 | 93 | 1±0.47ab | 0.44±0.19a | 1.86±2.07b | 5.43±2.18c |
| 53 | C1 | hexyl acetate | Est/8 | 23.86 | 56 | 1±0.86a | 0.46±0.10a | 0.98±0.22a | 3.91±0.65b |
| 54 | C1 | methyl nonanoate* | Est/9 | 30.91 | 74 | 1±0.51a | 0.45±0.17a | 1.02±0.11a | 6.04±1.81b |
| 55 | C1 | neryl acetatea | Est/10 | 34.97 | 69 | 1±0.55a | 0.20±0.07a | 1.90±0.19a | 15.53±5.87b |
| 56 | C1 | (Z)-3-hexen-1-ol | Alc/9 | 18.16 | 82 | 1±0.92a | 0.50±0.11a | 0.33±0.09a | 4.75±1.27b |
| 57 | C1 | methyl octanoate* | Est/11 | 27.74 | 74 | 1±0.49b | 0.41±0.05a | 0.44±0.08ab | 4.60±1.39c |
| 58 | C1 | geraniala | Ald/17 | 32.61 | 69 | 1±0.41a | 0.76±0.17a | 0.39±0.11a | 14.62±12.11b |
| 59 | C1 | geraniol | Alc/10 | 31.95 | 69 | 1±0.63a | 0.78±0.12a | 1.50±0.47a | 10.88±6.14b |
| 60 | C1 | heptyl acetateg * | Est/12 | 27.27 | 43 | - | - | - | 1±0.27 |
| 61 | C1 | methyl decanoate* | Est/13 | 33.94 | 74 | 1±0.82a | 3.78±1.48a | 3.14±0.92a | 72.44±42.64b |
| 62 | C1 | 1-nonanol | Alc/11 | 29.36 | 70 | 1±0.37a | 1.38±0.57a | 0.82±0.30a | 12.04±10.54b |
| 63 | C1 | undecanal | Ald/18 | 33.67 | 57 | 1±0.18ab | 1.23±0.19b | 0.76±0.09a | 1.21±0.63b |
| 64 | C1 | (E)-2-hexen-1-olf | Alc/12 | 18.48 | 57 | - | 1±0.75a | - | 2.72±0.80b |
| 65 | C1 | 1-decanolf | Alc/13 | 32.50 | 115 | - | 1±0.40a | 0.03±0.01a | 5.10±2.13b |
| 66 | C1 | 1-octanol | Alc/14 | 26.00 | 56 | 1±0.33a | 6.38±1.83a | 2.18±0.26a | 59.82±50.05b |
| 67 | C1 | 3-carene | Mt hd/5 | 24.43 | 93 | 1±0.56a | 14.10±8.38b | 1.39±0.64a | 78.68±4.74c |
| 68 | C2 | β-citronellola | Alc/15 | 31.15 | 81 | 1±0.53a | 1.47±0.39a | 4.53±0.45c | 2.21±0.16b |
| 69 | C2 | ethyl acetate | Est/14 | 9.18 | 61 | 1±0.42a | 5.28±1.55b | 40.71±7.12c | 3.70±1.37b |
| 70 | C2 | (Z)-carveola | Alc/16 | 31.84 | 109 | 1±0.49a | 4.77±1.76b | 6.91±0.85c | 4.85±1.98b |
| 71 | C2 | (E)-carveola | Alc/17 | 31.41 | 109 | 1±0.36a | 2.91±0.19b | 5.35±0.71c | 2.49±0.35b |
| 72 | C2 | carvonea | Ket/9 | 32.31 | 82 | 1±0.68a | 12.09±3.13c | 20.89±1.02d | 5.75±0.13b |
| 73 | C2 | linaloola | Alc/18 | 27.15 | 93 | 1±0.69a | 15.73±1.35c | 26.77±1.66d | 10.05±0.85b |
| 74 | C2 | ethanol | Alc/19 | 5.64 | 45 | 1±0.59a | 10.91±2.39c | 6.05±1.64b | 4.95±2.33b |
| 75 | C2 | acetaldehyde | Ald/19 | 4.77 | 43 | 1±0.25a | 3.07±0.84b | 2.75±0.22b | 2.96±0.49b |
| 76 | C2 | dodecanal | Ald/20 | 36.55 | 57 | 1±2.35a | 77.62±21.86d | 20.38±8.79b | 58.44±39.38c |
| 77 | C2 | 3-methylfuran* | Fur/4 | 9.16 | 82 | 1±0.32a | 4.25±1.60c | 2.91±0.94b | 2.51±0.33b |
| 78 | C2 | (E)-limonene oxideh | Mt cyc ether/2 | 28.84 | 94 | 1±0.77a | 7.53±2.60b | 6.81±4.59b | 5.98±3.14b |
| 79 | C2 | (Z)-limonene oxideh | Mt cyc ether/3 | 28.77 | 67 | 1±1.15a | 2.88±0.82b | 3.47±0.14b | 3.74±0.50b |
| 80 | C3 | camphene | Mt hd/6 | 22.44 | 93 | 1±1.04a | 1.37±0.17ab | 1.95±0.20b | 3.31±1.69c |
| 81 | C3 | terpinolene | Mt hd/7 | 27.05 | 121 | 1±0.40a | 3.19±0.18b | 4.78±0.33c | 6.11±1.01d |
| 82 | C3 | limonene | Mt hd/8 | 25.11 | 108 | 1±0.25a | 2.23±0.12b | 2.46±0.10b | 2.93±0.42c |
| 83 | C3 | α-pinene | Mt hd/9 | 21.67 | 93 | 1±0.41a | 6.17±0.92b | 9.17±1.18b | 18.56±9.66c |
| 84 | C3 | myrcene | Mt hd/10 | 23.28 | 91 | 1±0.42a | 2.54±0.37b | 3.21±0.28b | 5.58±1.78c |
| 85 | C3 | α-phellandrene | Mt hd/11 | 24.29 | 93 | 1±0.41a | 3.51±0.41b | 5.64±0.58b | 14.03±8.35c |
| 86 | C3 | α-terpineola | Alc/20 | 30.75 | 59 | 1±0.59a | 3.78±0.25b | 5.67±0.69c | 6.45±3.56c |
| 87 | C3 | γ-terpinene | Mt hd/12 | 26.03 | 93 | 1±0.61a | 2.97±0.44b | 5.16±0.85c | 5.34±2.62c |
| 88 | C3 | terpinen-4-ola | Alc/21 | 30.38 | 93 | 1±0.77a | 5.65±1.41b | 15.86±2.59d | 10.98±5.85c |
| 89 | C3 | nerala | Ald/21 | 31.81 | 84 | 1±0.55a | 4.28±1.43b | 6.21±0.69c | 7.32±1.45d |
| 90 | C3 | perillaldehydea | Ald/22 | 33.43 | 68 | 1±0.29a | 8.81±2.43b | 15.19±5.28c | 25.48±2.64d |
| 91 | C3 | α-terpinene | Mt hd/13 | 24.65 | 121 | 1±0.52a | 3.41±1.43b | 4.75±1.80c | 6.19±1.61d |
| 92 | C3 | ethyl nonanoate* | Est/15 | 33.05 | 88 | 1±0.91a | 0.41±0.15a | 5.59±1.51b | 6.88±1.16c |
| 93 | C3 | geranyl acetatea | Est/16 | 35.50 | 69 | 1±0.96a | 1.19±0.34a | 14.09±1.39b | 28.56±12.68c |
| 94 | C3 | (Z)-carvyl acetatea | Est/17 | 34.50 | 84 | 1±0.46a | 0.54±0.10a | 4.27±1.58b | 6.92±1.84b |
| 95 | C3 | (E)-carvyl acetatea | Est/18 | 35.30 | 84 | 1±1.17a | 0.62±0.15a | 7.36±4.56b | 4.79±0.55b |
| 96 | C3 | citronellyl acetatea | Est/19 | 34.69 | 95 | 1±0.62a | 0.94±0.31a | 47.41±4.01c | 19.52±3.25b |
| 97 | C3 | styrene* | Ar/2 | 20.01 | 104 | 1±0.30a | 2.41±0.91a | 2.90±0.68a | 15.10±5.92b |
| 98 | C3 | ethyl octanoate | Est/20 | 30.04 | 88 | 1±0.55a | 1.28±0.37a | 4.05±0.81b | 16.63±2.00c |
| 99 | C3 | nonyl acetate | Est/21 | 33.47 | 98 | 1±2.35a | 4.88±6.60a | 22.54±6.43a | 304.38±77.26b |
| 100 | C3 | ethyl butanoate | Est/22 | 15.88 | 88 | 1±2.036a | 17.58±4.13b | 27.11±5.07b | 113.73±54.23c |
| 101 | C3 | decyl acetate | Est/23 | 36.29 | 70 | 1±1.51a | 48.18±18.61b | 68.70±11.40c | 553.34±30.06d |
| 102 | C3 | α-terpinyl acetatea , f | Est/24 | 35.10 | 121 | - | 1±0.50a | 1.47±0.34b | 9.61±0.72c |
| 103 | C3 | linalyl acetatea | Est/25 | 31.82 | 93 | 1±0.47a | 7.09±4.24a | 7.29±0.92a | 83.29±21.54b |
| 104 | C3 | ethyl decanoate | Est/26 | 35.91 | 88 | 1±0.78a | 5.84±1.75ab | 16.43±3.04b | 62.91±32.20c |
| 105 | C3 | octyl acetate | Est/27 | 30.47 | 70 | 1±0.53a | 18.86±8.93a | 64.08±0.30b | 526.00±86.22c |
| 106 | 3-methylbutanal | Ald/23 | 10.66 | 58 | - | traces | - | - | |
| 107 | 1,4-cineole | Mt cyc ether/4 | 24.54 | 111 | - | traces | - | traces | |
| 108 | β-farnesene | Sqt/5 | 37.73 | 120 | - | - | - | traces | |
| 109 | γ-dodecalactone* | Ket/10 | 43.71 | 85 | traces | - | - | - |
Data are normalized to the mean values in the Chandler variety, unless otherwise indicated. Mean corresponding to n = 6 values. Means followed by different letters in the same row are significantly different (p<0.05) by Duncan's text. Family Code: Ald: Aldehyde; Ket: Ketone; Alc: Alcohol; Est: Ester; Fur: Furane; Mt hd: Monoterpene hydrocarbon; Sqt: Sesquiterpene; Ar: Aromatic hydrocarbon; Mt cyc ether: Monoterpene cyclic ether.
a
Monoterpene derived compound.
b
In addition to the alcohol group, it has a tetrahydrofuran group.
c
Sesquiterpene compound.
d
Norcarotenoid compound.
e
Data normalized to the mean abundance in Fortune variety.
f
Data normalized to the mean abundance in Clemenules variety.
g
Data normalized to the mean abundance in Powell variety.
h
Its cyclic ether group is an epoxy group.
*Compound reported for the first time in a Citrus juice.