Aroma Evaluation of Gamazumi (Viburnum dilatatum) by Aroma Extract Dilution Analysis and Odour Activity Value

Abstract

Viburnum dilatatum (gamazumi) is widely distributed in Japan and China. Recently, juice from V. dilatatum fruits has been manufactured in Japan. Concerning the aroma of V. dilatatum, phenethyl alcohol, 3Z-hexenol and l-linalool have been identified in the essential oil from the flowers of V. dilatatum, however, there are no detailed reports on the aroma of V. dilatatum elucidated using sensory evaluation. To clarify odourants contributing to the characteristic aroma, the aroma extract dilution analysis (AEDA) method was performed through gas chromatography olfactometry (GC-O) analysis. The aroma-active compounds were identified by GC-O and AEDA, and in order to determine the relative contribution of each compound to the aroma of V. dilatatum, odour activity value (OAV) has been used. The hydrodistillation of the leaf and branch of V. dilatatum afforded pale yellowish oils, with yields of 0.008 and 0.015% (w/w). The main components of the leaf oil were 3Z-hexenal (12.7%) and linalool (10.8%). In branch oil, palmitic acid (18.3%) and linoleic acid (8.2%) were identified. With regard to aroma components, 24 and 14 compounds were identified in the leaf and branch oils respectively, by GC-O analysis. On the basis of AEDA, OAVs and sensory evaluations, nonanal is estimated as the main aroma compound of leaf and branch oil, as the other aroma compounds, C₆ compounds and 2-pentyl furan make green odour; linalool, eugenol and β-ionone play important role in the sweet odour of leaf oil. In branch oil, cis-furanlinalool oxide and eugenol make sweet odour, and β-eudesmol contributes to woody odour.