The passing of the 21st Amendment to the United States Constitution has given to individual states the authority to regulate the sale, distribution and taxation of domestically produced wines, and made the wine trade potentially significant as a means of augmenting state revenues. In the state of Oregon, table wines have been taxed at the rate of 23 cents per gallon irrespective of origin. The objective of this study has been to evaluate the nature and price elasticity of Oregon's wholesale demand for California table wines with a view to determine the effectiveness of the utilization of the tax. The multiple regression analysis technique is the instrument used in this determination. A two part statistical model was employed, but the number of variables used had to be restricted because of certain data limitations. Only 78 percent and 50 percent of variation was explained in the price predicting and demand segments of the model respectively. The results of the statistical analysis indicated a positively sloped demand curve. This rendered any application of the concept of price elasticity of demand as a means of assessing how effective the tax was being used meaningless. In view of this, no recommendations have been made, but the need for further research as more data become available has been pointed out. / Graduation date: 1971

The purposeful induction of malolactic fermentation (MLF) in wines such as Pinot Noir and Chardonnay is an established commercial wine making practice in Oregon. This induction is not always successful, especially with white wines, such as Chardonnay. A study was initiated to examine the compatibility of yeasts commonly used in Oregon winemaking with various strains of malolactic bacteria. In preliminary and pilot plant scale experiments, the yeast strain found to be most conducive to malolactic fermentation by lactic acid bacteria was Montrachet (Red Star). The malolactic bacterial strains that were best able to complete malolactic fermentation in various wines, fermented by different yeast strains, were the two Oregon commercial strains, ER1A and Ey2d, and the Pinot Noir juice isolate, DAPN85A. Sensory analysis of aroma by difference from control test was done on Chardonnay wine fermented by 4 different yeast strains and 3 different malolactic bacterial strains. In all cases, there was an overall significant difference in malolactic fermented wine aroma when compared to control wines. Organic acid analyses by high pressure liquid chromatography (HPLC) and analyses of volatile compounds by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) were done on selected Chardonnay wines. Propionic acid was found to diminish in malolactic fermented wines while acetic acid content increased. Isobutanol and isobutyraldehyde increased significantly in MLF wines, compared to the controls. Chemical analyses of MLF and control wines suggested two possible chemical reactions resulting from the MLF. The first was the reduction of isobutyraldehyde to isobutanol, and the second was the hydrolysis of isobutyl acetate to isobutyraldehyde and acetate. On all GC chromatograms of wines, where MLF had occurred, there was an unidentified peak close to the retention time of isoamyl acetate. This peak was not evident in wines where MLF had not occurred. Eight compounds were tentatively identified by GC-MS in malolactic fermented wines which were not found in the control wines. These were 4-methyl-3-pentanoic acid, methyl acetate, ethyl hexanoate, hexyl acetate, 1,12-tridecadiene, hexadecanoic acid, and a compound which was tentatively identified as farnesol, or 1,2-benzenedicarboxylic acid. The latter four compounds had identity fits of less than 900 from the mass spectral analysis. Whether any of these eight compounds match the unknown "ML peak" found in the GC chromatograms is unknown. / Graduation date: 1989

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. / Graduation date: 1991

Includes a list of publications co-authored by the author during the preparation of this thesis. Bibliography: leaves 103-111. Studies the links between grape composition, wine composition and wine sensory properties. Developed a new method of measuring glycoside concentration in grapes (glycosyl-glucose assay) and a modified measurement of wine colour density in red wine. These were used to analyse samples of Shiraz grapes and wines from a comprehensive vineyard irrigation trial. Glycosyl-glucose concentrations shows promise for the prediction of wine composition and flavor intensity.

Heat induced protein haze is a common problem in white wine. Grape derived pathogenesis related proteins slowly denature and aggregate during wine storage and this gives rise to light dispersing haze. Protein haze formation is currently prevented by removing proteins using bentonite, an aluminium silicate clay, but this method has drawbacks. A potential alternative or complementary method is the use of haze protective factors ( HPF ), specific mannoproteins from Saccharomyces cerevisiae that visually reduce protein haze. Hpf1p was originally isolated from Muscat Gordo Blanco wine and Hpf2p from a synthetic grape juice ferment. Based on partial amino acid sequences, putative structural genes, HPF1 and HPF2, for these proteins were identified. HPF1 has a homologue, HPF1 ', ( 71 % similarity ) in S. cerevisiae. Sequence analysis suggests that Hpf1p, Hpf1 ' p and Hpf2p are localised to the cell wall or plasma membrane. This study aimed to determine the biological function of the HPF genes in S. cerevisiae. HPF overexpression and deletion strains were constructed and analysed for cell wall related phenotypes. Under a number of conditions, including cold temperature and ethanol stress, the hpf1 Δ hpf1 ' Δ strain was more tolerant than the wild type strain. However, mating efficiency of the hpf1 Δ hpf1 ' Δ strain was significantly less than the wild type strain and this was found to be correlated with the persistence of a septum between the mating partners. The decreased mating efficiency was also mating type specific, only occurring in MAT α cells. This study also aimed to establish conclusively that the HPF genes do indeed encode proteins with haze protective properties. Haze protective activity of the material from ferment supernatants was assessed. Material from the HPF deletion strains exhibited significantly less haze protective activity than the wild type. Moreover, material derived from HPF1 and HPF1 ' overexpressors was more active than material from the wild type. A 6xHis - tagged Hpf2p was expressed and purified using immobilised metal affinity chromatography. This Hpf2p had significant haze protective activity. Modification of N - glycans of 6xHis - Hpf2p by Endoglycosidase H decreased its haze protective activity.visually reduce protein haze. Hpf1p was originally isolated from Muscat Gordo Blanco wine and Hpf2p from a synthetic grape juice ferment. Based on partial amino acid sequences, putative structural genes, HPF1 and HPF2, for these proteins were identified. HPF1 has a homologue, HPF1 ', ( 71 % similarity ) in S. cerevisiae. Sequence analysis suggests that Hpf1p, Hpf1 ' p and Hpf2p are localised to the cell wall or plasma membrane. This study aimed to determine the biological function of the HPF genes in S. cerevisiae. HPF overexpression and deletion strains were constructed and analysed for cell wall related phenotypes. Under a number of conditions, including cold temperature and ethanol stress, the hpf1 Δ hpf1 ' Δ strain was more tolerant than the wild type strain. However, mating efficiency of the hpf1 Δ hpf1 ' Δ strain was significantly less than the wild type strain and this was found to be correlated with the persistence of a septum between the mating partners. The decreased mating efficiency was also mating type specific, only occurring in MAT α cells. This study also aimed to establish conclusively that the HPF genes do indeed encode proteins with haze protective properties. Haze protective activity of the material from ferment supernatants was assessed. Material from the HPF deletion strains exhibited significantly less haze protective activity than the wild type. Moreover, material derived from HPF1 and HPF1 ' overexpressors was more active than material from the wild type. A 6xHis - tagged Hpf2p was expressed and purified using immobilised metal affinity chromatography. This Hpf2p had significant haze protective activity. Modification of N - glycans of 6xHis - Hpf2p by Endoglycosidase H decreased its haze protective activity. / Thesis (Ph.D.)--School of Agriculture and Wine, 2003.

Bibliography: p. 227-253. / xvii, 254 p. : ill. (chiefly col.), photos (col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This project sought to examine the spatial and temporal distribution, as well as the composition, of the flavan-3-ols, proanthocyanidins and flavonols in winegrapes throughout berry development. In addition, the author sought to explore how modifying bunch exposure to light would impact upon flavonoid biosynthesis in the grape berry by comparing the flavonoid composition of shaded and exposed grapes. The expression of key genes in the flavonoid biosynthetic pathway was also investigated to understand how the pathway is regulated during berry development. / Thesis (Ph.D.)--University of Adelaide, School of Agriculture and Wine, Discipline of Wine and Horticulture, 2004

Bibliography: leaves 195-209. / xxvi, 209 leaves : ill., ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This study investigated seed development, phenolic composition of seeds and skins, and phenolic composition and sensory properties of wines made from berries of Vitis Vinifera L. cv. Shiraz that were developed and ripened under different levels of sunlight intensity at the bunch zone. The study also examined the relationships between seed and berry development, and the links between berry composition, wine composition and wine sensory properties. / Thesis (Ph.D.)--University of Adelaide, School of Agriculture and Wine, Discipline of Wine and Horticulture, 2004

Bibliography: leaves 200-214. / xi, 214 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Three structurally related compounds, 2-acetyltetrahydropyridine (ACTPY), 2-ethyltetrahydropyridine (ETPY) and N-heterocycle, 2-acetyl-1-pyrroline (ACPY), were quantified and found to be unique components of mousy wines. 35 lactic acid bacteria (LAB) were screened for the ability to produce mousy off-flavour. In addition to Lactobacillus brevis and L. cellobiosus, a diversity of LAB species, particularly heterofermentative Lactobacillus spp. and Oenococcus oeni exhibited this ability in a range of ethanolic and wine-based media. The substrates and metabolism of mousy compound formation by LAB were also investigated. A pathway for the formation of ACPY and ACTPY by heterofermentative LAB was proposed. / Thesis (Ph.D.)--University of Adelaide, Dept. of Horticulture, Viticulture & Oenology, 1999

Includes a list of publications co-authored by the author during the preparation of this thesis. / Bibliography: leaves 103-111. / vi, 111 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Studies the links between grape composition, wine composition and wine sensory properties. Developed a new method of measuring glycoside concentration in grapes (glycosyl-glucose assay) and a modified measurement of wine colour density in red wine. These were used to analyse samples of Shiraz grapes and wines from a comprehensive vineyard irrigation trial. Glycosyl-glucose concentrations shows promise for the prediction of wine composition and flavor intensity. / Thesis (Ph.D.)--University of Adelaide, Dept. of Horticulture, Viticulture and Oenology, 2001

Thesis (M.S. in food science)--Washington State University, December 2009. / Title from PDF title page (viewed on Jan. 19, 2010). "School of Food Science." Includes bibliographical references (p. 94-99).