45C-2 |
Analysis of flavor and flavor precursor in Pinot noir grape fruit by purge-trap gas chromatography/olfactometry-mass spectroscopy |
Y. FANG and M. C. Qian. Dept. of Food Science & Technology, Oregon State Univ., 100 Wiegand Hall, Corvallis, OR 97331-6602 Pinot noir is one of the oldest grape varieties to be cultivated for the purpose of making wine. And Pinot noir grape is also one of the most difficult grapes to grow and to make into fine wine. With its soft tannins and rich fruity and spicy flavors, Pinot noir is gathering considerable popularity in the United States. Because the population of this variety, considerable attention has focused on the flavor and flavor precursors changing in the grapes. However, flavor development in the grapes is not well understood. The objective of this experiment was to develop a quick method to analyze flavor and flavor precursors in pinot noir grapes. The Pinot noir grape samples were collected during October 2002 and kept at 4oC until analysis. Crushed fruits were analyzed directly or treated with acid and enzyme respectively. The headspace of sample was analyzed using purge-trap gas chromatography/olfactometry and mass spectroscopy. Using purge-trap and GCO/MS technique, more than 30 aroma compounds were identified in the hydrolyzed sample. Among them, only about 20 aroma compounds were detected in the untreated sample. Compared to the untreated sample, the volatiles in both hydrolyzed fruits have higher intensities, and different flavor were released from precursors by different treatments. These results suggested that the dynamic headspace analysis using purge-trap is a quick and useful method to analyze the flavor and flavor precursor in Pinot noir.
Session 45C, Food Chemistry: Flavor and aroma chemistry
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