Graduate Thesis Or Dissertation

 

A maturity trial study of Pinot noir wines : aroma profile by sniffing gas chromatographic effluent Public Deposited

Downloadable Content

Download PDF
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/7d278x27m

Descriptions

Attribute NameValues
Creator
Abstract
  • The quality of wine is highly influenced by the weather. Temperature, solar radiation and humidity influence the formation and concentration of aroma-active compounds and aroma-active precursors in the grapes. Pinot noir grapes require a slow ripening, under cool temperatures, in order to achieve their fullest flavor. The main objective of this study was to provide an overall aroma picture that could help, along with the chemical indices, to decide the optimum harvesting time to obtain certain distinctive aroma attributes in the wine. This particular work represents the first stage in a broad plan aimed to understand the dependence of the wine flavor chemistry on the ripening of the grapes. This maturity trial was planned to last several years; it was expected that the outcome and techniques developed in the present study would be essential in delineating the steps to follow. The results of the aroma analyses for the 1987 and 1988 vintages are reported here. In each vintage, Pinot noir grapes were harvested at three different times, covering a range from early to late maturity. A sniffing technique based on gas chromatographic aroma detection by a trained panel was implemented. This technique has proved to be a useful tool to measure qualities and intensities of aromas. The method was effective in detecting many of the aroma-active compounds and in identifying aroma differences between the wines studied. The aroma profiles for the wines were found to be very different from each other within and across vintages. There were only 10 aroma peaks common to all three 1987 wines, 16 aroma peaks common to the 1988 wines, and 4 aroma peaks common to both vintages. Late maturity wines had more aroma-active peaks than the other 2 wines for both vintages. The 1988 wines had a higher number of aroma-active peaks than the 1987 wines. The percentages of aroma-active peaks not detected by the Flame lonization Detector (FID) were 45% in the 1987 wines, and 66% in the 1988 wines. The overall climatic conditions in those years were very different. The 1987 season was characterized as hot and dry, producing an early harvest. The weather in 1988 was more of a typical season for Oregon, producing a normal to late harvest. Further study is needed to fully understand the flavor chemistry occurring during grape ripening.
Resource Type
Date Available
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Academic Affiliation
Non-Academic Affiliation
Subject
Rights Statement
Publisher
Peer Reviewed
Language
Digitization Specifications
  • File scanned at 300 ppi (Monochrome) using Scamax Scan+ V.1.0.32.10766 on a Scanmax 412CD by InoTec in PDF format. LuraDocument PDF Compressor V.5.8.71.50 used for pdf compression and textual OCR.
Replaces

Relationships

Parents:

This work has no parents.

In Collection:

Items