Effect of osmanthus hydrolat on the aroma quality and volatile components of osmanthus black tea.

ABSTRACT

Osmanthus fragrans is an evergreen shrub with a pleasant fragrance and a wide range of applications in many fields. The condensed hydrolat obtained during the drying process of its fresh flowers was collected in a low-temperature vacuum environment and its sensory evaluation and volatile components were studied. The main aroma compounds in Osmanthus fragrans were dihydro-ß-ionone, nonanal, ß-cyclocitral, ß-ionone, benzaldehyde, α-ionone, and 6-methyl-5-hepten-2-one, whose contents were used as the main evaluation criteria, and the hydrolats obtained under different scenting and drying times were compared. This process can effectively collect the aroma components in Osmanthus fragrans and the optimal drying conditions were 50 °C for 5 h. The hydrolat was used to provide the scent of osmanthus black tea, which had a fresher and mellower taste, while the fragrance of osmanthus was abundant. These results show that osmanthus hydrolat can be used to provide the scent of floral black tea. Chemical compounds studied in this article (-)-Catechin (PubChem CID 1203); (-)-epigallocatechin gallate (PubChem CID 65064); (-)-epicatechin gallate (PubChem CID 367141); (-)-epigallocatechin (PubChem CID 72277); (-)-epicatechin (PubChem CID 72276); (-)-gallocatechin gallate (PubChem CID 199472); (-)-catechin gallate (PubChem CID 6419835); (-)-gallocatechin (PubChem CID 9882981).