Table 2.
Volatile flavor compounds identified in nkui by SPME‐GC×GC‐TOF‐MS, their group classification and flavor descriptors
| Name | RT (s) | Quantity (%) | Flavor descriptorsa |
|---|---|---|---|
| Acids | |||
| Butanoic acid | 692.6 | 0.002 ± 0.00 | Butter, acidic, fruity, rose |
| Acetic acid | 716.6 | 1.712 ± 0.79 | Vinegar, sour, pungent |
| Propanoic acid | 806.7 | 0.002 ± 0.00 | Acidic, diary, fruity |
| 3,3‐dimethylacrylic acid | 857.5 | 0.002 ± 0.02 | Green, phenolic, diary |
| Butanoic acid, 3‐methyl‐ | 929.9 | 0.002 ± 0.00 | Cheese, dairy, creamy |
| Hexanoic acid | 1,077.3 | 0.009 ± 0.00 | Fatty, cheesy, fruity |
| Hexanoic acid, 2‐ethyl‐ | 1,160.8 | 0.003 ± 0.00 | Oily rancid, sweat‐like |
| Nonanoic acid | 1,317.1 | 0.004 ± 0.00 | Waxy, fatty cheesy |
| Alcohols | |||
| 1‐octen‐3‐ol | 728.8 | 0.035 ± 0.01 | Sweet, Mushroom, earthy, fungal |
| 4‐thujanol, stereoisomer | 739.5 | 0.224 ± 0.31 | Cooly, minty |
| Bicyclo[3.1.1]hept‐3‐en‐2‐ol, 4,6,6‐trimethyl‐, [1s‐(1à,2á,5à)]‐ | 792.7 | 0.069 ± 0.05 | Pine, ozone |
| Linalool | 827.9 | 17.849 ± 7.18 | Citrus, orange, floral |
| 1,2‐propanediol | 856.4 | 0.028 ± 0.02 | Odorless/fatty aroma |
| 1,5,7‐octatrien‐3‐ol, 3,7‐dimethyl‐ | 882.1 | 0.021 ± 0.02 | Moldy |
| Terpinen‐4‐ol | 896.0 | 0.159 ± 0.09 | Woody, earthy, musty |
| Pinocarveol | 918.9 | 0.012 ± 0.01 | Camphoreous, pine, woody |
| Trans‐piperitol | 942.2 | 0.067 ± 0.05 | Herbal |
| Trans‐carveol | 948.2 | 0.028 ± 0.03 | Caraway, solvent, spearmint |
| Farnesol | 972.9 | 0.013 ± 0.04 | Floral, juicy, green |
| 2,6‐octadien‐1‐ol, 3,7‐dimethyl‐, (E)‐ | 1,084.0 | 4.438 ± 5.98 | Floral |
| Nerolidol | 1,233.3 | 0.022 ± 0.01 | Green, floral, fruity |
| Thymol | 1,341.4 | 0.002 ± 0.00 | Medicinal spicy |
| Aldehydes | |||
| Nonanal | 664.6 | 0.053 ± 0.03 | Green, fat, citrus |
| Bicyclo[3.1.1]hept‐2‐ene‐2‐carboxaldehyde, 6,6‐dimethyl‐ | 891.1 | 0.031 ± 0.01 | Spicy, herbaceous |
| 2,6‐octadienal, 3,7‐dimethyl‐ | 941.1 | 0.139 ± 0.01 | Lemon |
| Cinnamaldehyde | 1,064.0 | 0.008 ± 0.00 | Cinnamon, spicy |
| Lilac aldehyde D | 1,151.9 | 0.069 ± 0.03 | Floral, lilac |
| Aromatic compounds | |||
| Benzene, 1‐methyl‐4‐(1‐methylethyl)‐ | 516.6 | 8.212 ± 9.10 | Spicy, balsamic, musty |
| Benzene, 1‐methyl‐2‐(1‐methylethyl)‐ | 519.2 | 1.764 ± 0.08 | Green, rubber |
| Benzene, 1‐methyl‐4‐(1‐methylethenyl)‐ | 708.7 | 0.077 ± 0.02 | Spicy, balsamic, musty |
| Benzaldehyde | 790.3 | 0.031 ± 0.01 | Nutty, bitter, woody |
| Linalyl anthranilate | 839.9 | 13.372 ± 0.11 | Fresh, linalool, orange, blossom |
| Benzaldehyde, 4‐(1‐methylethyl)‐ | 1,023.4 | 0.025 ± 0.00 | Nutty, bitter |
| Benzenemethanol, à,à,4‐trimethyl‐ | 1,081.3 | 0.046 ± 0.04 | Sweet, fruity, cherry |
| Quinoxaline, 5‐methyl‐ | 1,169.0 | 0.014 ± 0.01 | Nutty, peanut, roasted |
| Benzenemethanol, 4‐(1‐methylethyl)‐ | 1,270.1 | 0.007 ± 0.01 | Cumin, spicy, floral |
| Esters | |||
| Ethyl acetate | 129.3 | 0.783 ± 0.03 | Fruity, brandy‐like |
| Isononyl acetate | 674.8 | 0.004 ± 0.00 | Herbal, woody |
| (Z)‐3‐hexenyl acetate | 701.7 | 0.015 ± 0.08 | Green, fruity, apple pear |
| 1,6‐octadien‐3‐ol, 3,7‐dimethyl‐, acetate | 837.4 | 10.345 ± 8.59 | Bergamot, lavender |
| Linalyl acetate | 840.3 | 19.088 ± 0.12 | Sweet, green, citrus |
| Terpinyl propionate | 887.1 | 1.501 ± 1.12 | Floral, lavender |
| Geranyl formate | 968.3 | 0.079 ± 0.00 | Green floral |
| Neryl acetate | 987.1 | 0.849 ± 0.04 | Green, citrus like |
| 2,6‐octadien‐1‐ol, 3,7‐dimethyl‐, acetate | 1,013.1 | 2.344 ± 1.54 | Floral, rosy, sweet |
| Furan compounds | |||
| Furanoid | 715.5 | 0.320 ± 0.02 | Earthy, floral, sweet, woody |
| 2‐furanmethanol, 5‐ethenyltetrahydro‐à,à,5‐trimethyl‐, cis‐ | 744.6 | 0.725 ± 1.33 | Earthy, floral, sweet |
| Rosefuran epoxide | 875.7 | 0.010 ± 0.01 | Green, earthy, citrus |
| Furan, 2‐ethyl‐5‐methyl‐/2‐ethyl‐5‐methylfuran | 1,260.1 | 0.006 ± 0.01 | Gassy, burnt |
| Ketones | |||
| 6‐methyl‐5‐hepten‐2‐one | 597.9 | 0.632 ± 0.37 | Green, vegetable, musty, mushroom |
| 2‐nonanone | 659.1 | 0.464 ± 0.04 | Fruity, herbaceous |
| Bicyclo[2.2.1]heptan‐2‐one, 1,7,7‐trimethyl‐, (1s)‐ | 781.4 | 0.032 ± 0.04 | Camphoreous |
| 4‐isopropylcyclohex‐2‐en‐1‐one | 800.2 | 0.017 ± 0.01 | Spicy, cummy, caraway |
| Cyclohexanone, 5‐methyl‐2‐(1‐methylethylidene)‐, (r)‐ | 886.2 | 0.029 ± 0.03 | Peppermint, camphor |
| Umbellulone | 902.9 | 0.001 ± 0.00 | Minty, pungent |
| Cryptone | 925.4 | 0.013 ± 0.01 | |
| 2‐acetyl‐3,5‐dimethylpyrazine | 933.2 | 0.080 ± 0.06 | Nutty, roasted, hazelnut |
| Piperitone | 976.8 | 0.075 ± 0.05 | Herbal, minty |
| Ethyl maltol | 1,201.5 | 0.003 ± 0.00 | Sweet |
| 5‐methyl‐3,5‐octadien‐2‐one | 1,227.5 | 0.021 ± 0.02 | Buttery, woody |
| 7‐Oxabicyclo[4.1.0]heptan‐2‐one, 6‐methyl‐3‐(1‐methylethylidene)‐ | 1,426.3 | 0.126 ± 0.18 | Herbal, minty |
| Phenols | |||
| Phenol | 1,198.1 | 0.026 ± 0.01 | Sweet, medicinal |
| Phenol, 5‐methyl‐2‐(1‐methylethyl)‐ | 1,319.1 | 0.025 ± 0.07 | Aromatic, Sweet, medicinal |
| Phenol, 2‐methyl‐5‐(1‐methylethyl)‐ | 1,349.2 | 0.078 ± 0.08 | Pungent |
| Phenol, 3‐(1‐methylethyl)‐ | 1,352.3 | 0.029 ± 0.00 | Sweet, medicinal |
| Phenol, 5‐methyl‐2‐(1‐methylethyl)‐ | 1,319.1 | 0.025 ± 0.07 | Aromatic, Sweet, medicinal |
| Sulphur compounds | |||
| Trisulfide, dimethyl | 639.9 | 0.351 ± 0.16 | Sulphurous, alliaceous, eggy |
| Disulfide, methyl (methylthio)methyl | 1,085.7 | 3.578 ± 6.59 | Sulphurous, onion |
| Terpenes/Terpenoids | |||
| Eucalyptol (1,8‐cineole) | 423.3 | 0.895 ± 0.05 | Minty, eucalyptoid |
| Cyclohexene, 1‐methyl‐4‐(1‐methylethylidene)‐ | 530.4 | 0.261 ± 0.12 | Fresh, sweet, woody, citrus, pine |
| 3,7‐dimethyl‐1,3,6‐octatriene | 739.8 | 0.453 ± 0.08 | Woody, tropical, floral |
| δ‐Elemene | 749.3 | 0.013 ± 0.04 | Sweet herbal, woody |
| Tricyclo[4.4.0.0(2,7)]dec‐3‐ene, 1,3‐dimethyl‐8‐(1‐methylethyl)‐ | 768.8 | 1.013 ± 0.94 | Woody, spicy, honey |
| Methacrolein | 782.4 | 0.010 ± 0.01 | Floral |
| Naphthalene, 1,2,3,4,4a,5,6,8a‐octahydro‐7‐methyl‐4‐methylene‐1‐(1‐methylethyl)‐, (1à,4aà,8aà)‐ | 815.9 | 0.047 ± 0.02 | Fresh, woody |
| α‐zingiberene | 817.6 | 0.914 ± 0.01 | Spice, fresh |
| trans‐à‐Bergamotene | 850.1 | 0.224 ± 0.09 | Woody, warm, tea |
| α‐Santalene | 852.8 | 1.144 ± 0.24 | Woody |
| β‐Caryophyllene | 866.2 | 1.075 ± 1.04 | Spicy, peppery, woody |
| α‐Cubebene | 901.7 | 0.010 ± 0.00 | Herbal, earthy |
| Epi‐β‐santalene | 906.3 | 0.008 ± 0.00 | Woody |
| Terpinyl acetate<delta‐> | 918.4 | 0.014 ± 0.01 | Sweet, herbaceous |
| α‐Caryophyllene | 933.7 | 0.389 ± 0.07 | Musty, green |
| Farnesene<(E)‐β‐ | 950.1 | 0.002 ± 0.01 | Fruity, woody, citrus, sweet |
| Bisabolene<(Z)‐α‐ | 1,028.3 | 0.089 ± 0.10 | Sweet, spicy, balsamic |
| cis‐Carveol | 1,095.4 | 0.070 ± 0.07 | Spicy, caraway |
| α‐Phellandrene | 1,099.0 | 1.993 ± 2.96 | Peppery |
| 2,3‐dioxabicyclo[2.2.2]oct‐5‐ene, 1‐methyl‐4‐(1‐methylethyl)‐ | 1,146.5 | 0.264 ± 0.18 | Fatty, herbaceous |
| Limonene dioxide | 1,152.2 | 0.065 ± 0.02 | Citrus‐like, green |
| Carvacrol | 1,341.5 | 0.004 ± 0.02 | Pungent |
| Miscellaneous compounds | |||
| Butylhydroxytoluen (BHT) | 1,136.8 | 0.016 ± 0.02 | Mild, phenolic, camphor |
| Tris(methyl thio) methane | 1,194.3 | 0.623 ± 0.87 | Earthy, mushroom, musty |
Notes. RT: retention time (in s).
a
Flavor compounds were identified using the following references (Adams, R. P. 1995. Identification of essential oil components by gas chromatography/mass spectrometry. Allured Publishing Corporation, Carol Stream, IL; Weyerstahl, P., Marschall, H., Thefeld, K., & Subba, G. C. 1998. Constituents of the essential oil from the rhizomes of Hedychium gardnerianum Roscoe. Flavour and Fragrance Journal, 13, 377–388; Jirovetz, L., Buchbauer, G., Stoyanova, A. S., Georgiev, E. V., & Damianova, S. T. 2003. Composition, quality control, and antimicrobial activity of the essential oil of long‐time stored dill (Anethum graveolens L.) seeds from Bulgaria. Journal of Agricultural and Food Chemistry, 51, 3854–3857; Behera, S., Nagarajan, S., & Rao, L. J. M. 2004. Microwave heating and conventional roasting of cumin seeds (Cuminum cyminum L.) and effect on chemical composition of volatiles. Food Chemistry, 87, 25–29; Burdock, G. A. (2010). Fenaroli's handbook of flavor ingredients 6th ed. CRC Press, NW, Boca Raton. http://www.google.com/patents/US4301184; http://www.thegoodscentscompany.com; http://www.perflavory.com).