Background and Aims:Relationships between the chemical composition and the sensory perception of red wines are generally poorly understood. In New Zealand, the vineyard area of Pinot Noir has increased markedly and wines from this red cultivar now constitute a significant proportion of total production. The aim of this study was to identify aroma compounds of major sensory significance in New Zealand Pinot Noir wines. Methods and Results: The concentration of 34 aroma chemicals in 32 New Zealand Pinot Noir wines was quantified using three separate solid-phase microextraction-GC-MS methods. Relationships between these chemical data and sensory data obtained from the same wines were investigated with canonical correlation analysis. Subsequently, correlation results were validated with addition/omissions tests. Ethyl octanoate was found to increase red cherry aroma, the combination of ethyl octanoate and ethyl decanoate enhanced black cherry aroma, and 2-phenyl ethanol increased violet aroma. Benzaldehyde altered Pinot Noir aroma but its effect on specific attributes was unclear. Conclusions: The influence of benzaldehyde, ethyl octanoate and 2-phenyl ethanol on the aroma of Pinot Noir wine was consistent with previous studies conducted on Merlot and Cabernet Sauvignon wines. This indicated that the contribution of these compounds is similar in a range of red wines. Ethyl decanoate appeared to act as an aroma enhancer compound when in combination with ethyl octanoate. Significance of the Study: Improved knowledge of key aroma and flavour components and the factors that influence their concentration is required to allow producers to manipulate better sensory characteristics to meet the preferences of specific markets. This study provides new information on important aroma compounds in New Zealand Pinot Noir which can lead to future research on modulating factors. 376Chemistry and sensory of New Zealand Pinot Noir

Conventional solvent extraction (CE) and ultrasound-assisted extraction (UE) were systematically optimized for fruit (blueberries, cherries, and red pear peels) with different anthocyanin compositions to pursue high recovery of polyphenols and anthocyanins with high antioxidant activity in this study. The effects of the extraction methods and conditions on anthocyanin compositions in different fruit were also analyzed by HPLC. The optimum were identified as: 60% methanol, 50 °C, 1 h using CE or 70% methanol, 30 °C, 20 min using UE for blueberries; 60% ethanol, 70 °C, 1 h using CE or 80% ethanol, 30 °C, 20 min using UE for cherries; 60% methanol, 50 °C, 1 h using CE or 60% ethanol, 30 °C, 60 min using UE for red pear peels. From analysis, ultrasound specifically enhanced the extraction of total monomeric anthocyanins from fruit by dissociating polymeric anthocyanins in less polar solvent system. HPLC analysis revealed that both extraction methods and conditions altered the amount of specific anthocyanin compounds in fruit extracts, including delphinidin, cyanidin, petunidin, pelargonidin, peonidin, or malvidin with different sugar moiety. Therefore, different conditions for CE and UE might be implemented for specific fruit with different anthocyanin compositions for maximizing the recovery of anthocyanins.

Monoterpenes are aromatic compounds that are of great interest to wine as they are related to the quality of varietal wines. However, there is little information available about the impact of monoterpenes on wine odor perception at sub-or perithreshold concentrations. The aim of this study was to investigate odor perception of monoterpene isomers in Pinot Gris wine and determine compositional matrix effects. Monoterpene isomers were quantitated in 46 Pinot Gris wines using headspace solid-phase microextraction−multidimensional gas chromatography−mass spectrometry, and sensory analysis was conducted using three different model wines. Results show that the nonvolatile composition of Pinot Gris wine strongly increased the volatility of monoterpene isomers. However, aromatic compounds suppressed odor perception, especially with the more complex monoterpene profiles. Monoterpenes were found to influence some fruity aromas in Pinot Gris. The knowledge of these interactions will further help in the development of wine styles and our understanding of wine quality.

A valid quantitative method for the analysis of chiral monoterpenes in white wine using head-space solid phase micro-extraction-MDGC-MS (HS-SPME-MDGC-MS) with stable isotope dilution analysis was established. Fifteen compounds: (S)-(−)-limonene, (R)-(+)-limonene, (+)-(2R,4S)-cis-rose oxide, (−)-(2S,4R)-cis-rose oxide, (−)-(2R,4R)-trans-rose oxide, (+)-(2S,4S)-cis-rose oxide, furanoid (+)-trans-linalool oxide, furanoid (−)-cis-linalool oxide, furanoid (−)-trans-linalool oxide, furanoid (+)-cis-linalool oxide, (−)-linalool, (+)-linalool, (−)-α-terpineol, (+)-α-terpineol and (R)-(+)-β-citronellol were quantified. Two calibration curves were plotted for different wine bases, with varying residual sugar content, and three calibration curves for each wine base were investigated during a single fiber’s lifetime. This was needed as both sugar content and fiber life impacted the quantification of the chiral terpenes. The chiral monoterpene content of six Pinot Gris wines and six Riesling wines was then analyzed using the verified method. ANOVA with Tukey multiple comparisons showed significant differences for each of the detected chiral compounds in all 12 wines. PCA score plots showed a clear separation between the Riesling and Pinot Gris wines. Riesling wines had greater number of chiral terpenes in comparison to Pinot Gris wines. Beyond total terpene content it is possible that the differences in chiral terpene content may be driving the aromatic differences in white wines.

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