Abstract
The volatile components of Tosa-buntan (Citrus grandis Osbeck forma Tosa) cold-pressed peel oil were studied by GC and GC-MS. The characteristic aroma compounds were investigated by GC-olfactometry in which a semi-bore capillary column, DB-Wax, was used for effective separation of the volatile components of the oil. Hydrocarbons including mono and sesquiterpenes of the oil accounted for about 98% of the volatile components. The characteristic flavor was also present in the oxygenated fraction. Flavor dilution (FD) factors of the volatile flavor components of the cold-pressed oil were determined by aroma extraction dilution analysis. The relative flavor activity derived from FD-factor and peak area percent was used in this experiment. It was suggested that compounds with higher relative flavor activity such as decanoic acid, heptyl acetate, a-bisabolol, nonanal, cis, trans-farnesol, trans-nerolidol and 2-dodecenal would contribute to Tosa-buntan flavor. Careful sniff testing revealed 2-dodecenal to be a characteristic or key compound of Tosa-buntan aroma. A solution of this authentic compound below 2 ppm gave a pleasant and refreshing aroma similar to Tosa-buntan flavor.