Abstract
The constituents of the neutral volatiles in air-cured Burley tobacco were studied, and the following 19 substances were newly added to our lists:
1. 6-Methyl-6,9-oxidonon-4-en-2-ol
2. 5-Isopropylnon-3-en-2,8-dioI
3. 5-Isopropylnonan-2,8-diol
4. 3,3,5-Trimethyl-8-isopropyl-4,9-dioxabicyclo-[3.3.1]nonan-2-oI
5. 2-(1-Methyl-4-isopropyl-7,8-dioxabicyclo[3.2.1]-octan-6-yl)propan-2-ol
6. 3-Oxoactinidol
7. 5-Isopropyl-7-(2-methyltetrahydrofur-2-yl)hept-6-en-2-ol
8. O-Methyl acetophenone
9. 1,5,5-Trimethyl-9-oxabicyclo[4.3.0]nonan-3-one
10. 4-(3-Hydroxybutylidene)-3,5,5-trimethylcyclohex-2-en-1-one
11. (1-Methyl-4-isopropyl-7,8-dioxabicyclo[3.2.1]-octan-6-yl)methyl ketone
12. 6,10-Dimethyl-2-(1-methylethenyl)spiro[4.5]dec-6-en-8-one (solavetivone)
13. 5-Isopropyl-7-(2-methyltetrahydrofur-2-yl)hept-6-en-2-one
14. 4-Ethyl-4-methylbutan-4-olide
15. Phthalide
16. Hydroxydihydrobovolide
17. 1,2-Dimethoxy benzene
18. o-Anisidine
19. Methylanthranilate
A large number of identified compounds may be viewed as degradation products of carotenoids and thunberganoids. These compounds have a characteristic aroma and are thought to be key flavour components in the essential oils of tobacco. The presence of any labdanoid hydrocarbons or their oxygenated products was not recognized in our Burley tobacco extract. Burley tobacco is thought to be deficient in labdanoid compounds.