Characterization of volatile components of tea flowers (Camellia sinensis) growing in Kangra by GC/MS.
ABSTRACT Volatile flavour components of tea flowers (Camellia sinensis) were isolated by two methods viz. simultaneous distillation extraction (SDE), supercritical fluid extraction (SFE), analyzed by GC and GC/MS and compared with headspace analysis (HS). The composition of the volatile components extracted by the three methods differed considerably. In SFE, phenylethanol (14.7%), linalool (7.9%), (E)-linalool oxide furanoid (3.5%), epoxy linalool (1.6%), geraniol (2.3%) and hotrienol (1.5%) were major components. m-Xylene (2.6%), (E)-linalool oxide pyranoid (5.4%), p-myrcene (5.2%), alpha-cadinol (4.3%) and methyl palmitate (2.9%) were major compounds isolated by SDE. 3-hexenol (2.1%) (E)-4,8-dimethyl-1,3,7-nonatriene (20.9%) and linalool (35.1%) are major components in headspace analysis. Acetophenone and pheromone germacrene D is detected in tea flowers by all the methods studied. Floral, fresh and fruity odour of tea flowers is retained by SFE as there is very little loss of heat sensitive volatiles in SFE. The flavour isolated from SFE has superior quality compared to SDE.
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ABSTRACT: BACKGROUND: To extract natural volatile compounds from tea (Camellia sinensis) flowers without thermal degradation and residue of organic solvents, supercritical carbon dioxide extraction (SFE) was employed to prepare essential oil of tea flowers in the present study. Four important parameters including pressure, temperature, and extraction time (static and dynamic) were selected as independent variables in the SFE. RESULTS: The optimum extraction conditions were the pressure of 30 MPa, temperature of 50°C, static time of 10 min, and dynamic time of 90 min. Based on GC-MS analysis, 59 compounds including alkanes (45.4%), esters (10.5%), ketones (7.1%), aldehydes (3.7%), terpenes (3.7%), acids (2.1%), alcohols (1.6%), ethers (1.3%), and others (10.3%) were identified in the essential oil of tea flowers. Moreover, the essential oil of tea flowers showed relatively stronger DPPH radical scavenging activity than essential oils of geranium and peppermint, although its antioxidative activity was weaker than those of essential oil of clove, ascorbic acid, tertiary butylhydroquinone, and butylated hydroxyanisole. CONCLUSION: Essential oil of tea flowers using SFE contained many kinds of volatile compounds and showed considerable DPPH scavenging activity. The information will contribute to the future application of tea flowers as raw materials in health-care food and food flavor industries.Journal of the Science of Food and Agriculture 06/2013; · 1.76 Impact Factor