Characterization of the Aroma of Central Otago Pinot noir Wines Using Sensory Reconstitution Studies

Abstract

The aroma of two representative Pinot noir wines over two consecutive vintages from the Central Otago region of New Zealand underwent gas chromatography olfactory analysis. Forty-two odorants were identified in the aroma extract dilution analysis (AEDA) study with flavor dilution (FD) factors ranging from 3 to 19,683, with over 20 having FD > 81. The highest FDs were for phenylethyl alcohol (rose), ethyl isobutyrate (strawberry), β-damascenone (tea, floral), isovaleric acid (cheese), ethyl isovalerate (fruit, cherry), ethyl cinnamate (honey, cinnamon), and guaiacol (medicinal, smoky). Following AEDA studies, 51 compounds were quantified via GC–MS following liquid-liquid extractions, of which 22 were present at levels above perception threshold. The odorants with the highest odor activity values were β-damascenone, ethyl octanoate, ethyl hexanoate, ethyl isovalerate, isovaleric acid, and 3-mercapto-hexanol, with values ranging from 17 to 95. Using the data from these screening methods, aroma models were prepared by deodorizing two Pinot noir wines with LiChrolut EN resin and reconstituting the wines using purified aroma standards. Five further models for each wine were prepared in the same manner but with the omission of one major aroma family, and the models were presented to a trained panel. When compared to the fully reconstituted model, the omission treatments altered certain sensory descriptors, although overall no profound differences were observed and no genuine impact compounds were revealed.