Thesis (Ph.D.)--University of Nebraska-Lincoln, 2009. / Title from title screen (site viewed January 5, 2010). PDF text: x, 291 p. : ill. (some col.) ; 3 Mb. UMI publication number: AAT 3360082. Includes bibliographical references. Also available in microfilm and microfiche formats.

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Thesis (Ph.D.)--University of Texas at Arlington, 2009.

Thesis (Ph.D.)--University of Texas at Arlington, 2009.

Thesis (M.S.)--University of Wisconsin--Madison, 1962. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 46-48).

Thesis (M.S. in Chemical Engineering)--University of California, Berkeley, April 1958. / Includes bibliographical references (leaves 170-171).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1964. / Typescript. Vita. Description based on print version record. Includes bibliographical references (leaves 138-145).

The use of gas chromatography for the separation, comparison, and subsequent identification of flavor volatiles from food products has proven highly successful in recent years. The development of various techniques for the concentration of the volatiles before gas chromatographic analysis has greatly extended the use of this important analytical tool. The injection of vapors directly into the chromatograph without prior concentration is the simplest method and has been used successfully on many food products. However, the use of this technique on the volatiles of fishery products has met with limited success. The complexity and nature of the flavor compounds found in fishery products have required the use of highly sensitive instruments and columns with very efficient separation power. The purpose of this investigation was to develop a method for the separation and comparison of volatiles from fishery products by this direct vapor injection technique. Preliminary investigations showed that a nine foot column of diisodecyl phthalate on 80/100 mesh, methanoic KOH treated, celite 545, operated isothermally at 35°C, would give satisfactory separation of one to three ml samples of volatiles from heated fishery products. The technique was not, however, sensitive enough to allow direct sampling of cold products unless they were highly spoiled or autoxidized. This investigation showed that direct vapor injection, using the column and conditions described, will show differences between size and number of peaks in heated fresh, oxidized, and spoiled fishery products. Several peaks in autoxidizing menhaden oil were shown to increase with hours of oxidation and a peak with the same retention time as trimethylamine was observed in the chromatograms of spoiled fish. The direct injection technique did not show large differences between fresh dover sole, rockfish, oysters, or beef. Tentative identification of various peaks from the chromatograms of oxidized salmon oil was attempted by comparison of retention data to known compounds and by functional group analysis by the method of Hoff and Feit (34). In this manner the possible existance of C₁ to C₇ alkanals, 2-hexen-1-al, methane, heptane, ethanol, butanol, and acetone was shown. The methods of tentative identification used were preliminary in nature and confirming tests would be necessary before positive identifications could be made. A comparison of chromatograms from fish, oysters, beef, and fish oils showed that several similar peaks appear in every case. These peaks were found at retention times of 0.71, 0.87, 1.42, 2.21, 2.83, 3.62, 5.20, and 5.51 minutes. / Graduation date: 1964

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