La exposición de las plantas de vid a bajas temperaturas es uno de los factores que provocan la “coulure”. Este fenómeno involucra la aparición de perturbaciones a nivel de la fotosíntesis y el metabolismo del carbono de la planta. Con el fin de analizar el efecto de una noche fría sobre el contenido de los azúcares de reserva de las inflorescencias de Pinot noir, se expusieron ramas fructíferas de esta cepa de vid a temperaturas de 4°, 0° y -3°C durante una noche, para posteriormente determinar el contenido de glúcidos (glucosa, fructosa, sacarosa y almidón) de las inflorescencias. En paralelo, se realizaron observaciones microscópicas de las reservas amiláceas de las inflorescencias sometidas a una noche a -3°C. Los resultados de este estudio muestran que los contenidos en glucosa y fructosa de las inflorescencias fluctúan durante las primeras horas luego de un estrés de 4° y 0°C. Sin embargo, es sobre todo luego de una noche a -3°C que se pudo constatar una fuerte movilización y consumo de los azúcares de reserva contenidos en las inflorescencias estresadas. -- Palabras clave: Estrés frío, glúcidos, inflorescencia, vid, coulure. / -- Exposure to low temperatures is one of the main factors causing the coulure in grapevine, due to its effect on the plant’s photosynthesis and carbon metabolism. To test the effect of a chilling night on carbon reserves of inflorescences of Pinot Noir, fruiting cuttings that have undergone a low-temperature night at 4°, 0° and -3 ° C were used to determine the levels of carbohydrates (glucose, fructose, sucrose and starch) in the inflorescences. Microscopic observations of inflorescences after a -3 ° C night were performed. The levels of glucose and fructose fluctuated during the first hours after a 4 and 0 ° C night, but it is especially after a chilling night at -3 ° C that a strong mobilization and consumption of carbohydrates in the inflorescence were observed. -- Key words: Cold stress, carbohydrates, inflorescence, grapevine, coulure.

This thesis deals with the problem of usage of stems while vinification while the results are bouth analytic and sensoric as well.

Thesis (Ph. D.)--Oregon State University, 2007. / Printout. Includes bibliographical references. Also available on the World Wide Web.

A number of methods to isolate and quantify protein in Pinot noir wines were evaluated. The combination of precipitation by acetone containing 10% w/v trichloroacetic acid followed by quantification with the Bradford assay, reported in yeast invertase equivalents yielded the most accurate results when compared to micro-Kjeldahl analysis. The technique was validated by dialysis and proteolysis experiments and was used to assay protein in 57 Pinot noir wines. These wines were found to contain protein concentrations ranging from 49 to 102 mg/L. The mannan and tannin content of the wines was also measured, but no correlation between protein content and concentrations of these components was found. The presence of protein in red wines greater than 30 years old at concentrations typically found in white wines contradicts the notion that interactions with tannin severely reduce protein levels. / Graduation date: 2011

Thesis (Ph. D.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 270-288). Also available on the World Wide Web.

Pinot noir has a reputation for lower color stability than other red wine varieties. Because it has relatively low anthocyanin and phenolic content and lacks acylated anthocyanin pigments compared to other red vinifera varieties, color extraction and stability are particularly important. Varying the processing during fermentation of red wine can produce high quality wines. Pectolytic enzymes are used in wine processing for many purposes from increasing juice yield and filtering rates to improving color and phenolic extraction. Macerating enzymes used in this study, Scottzyme Color Pro (Scott Laboratories), Scottzyme Color X (Scott Laboratories), Lallzyme EX (Lallemand), GB Rapidase EX Color (Gist Brocades), and Vinozyme G (Cellulo) were added to 1997 Oregon Pinot noir must prior to fermentation to observe color, aroma and flavor changes. These commercial enzymes have been reported to increase color and improve aroma and flavor of red wines. The effect of these enzymes had not previously been investigated on Oregon Pinot noir but the manufacturers reported increased polymeric phenols, polymeric anthocyanins, tannins, color stability, red hue and saturation of red wine varieties. These enzymes have varying manufacturer recommended usage levels and it is not known how the dosage levels and the enzymes themselves affect Oregon Pinot noir. Sensory evaluations of these wines, at a high and low dosage level, were conducted through free-choice profiling by winemakers and descriptive analysis from a trained panel. In addition, chemical analyses were performed and related to sensory panel results. Overall the addition of these enzymes to Oregon Pinot noir produced wines with greater purple, red descriptors and higher color intensity than the control wine from trained descriptive panel and winemaker panel results. In aroma, the enzyme treated wines were higher in vegetative and earthy descriptors compared to the control. GB Rapidase EX Color (Gist Brocades) was higher in bitterness flavor compared with other samples. Low enzyme wine treatments separated wine samples more from the control then high enzyme wine treatments. The color and appearance, aroma and flavor axes of the profile maps were not significant in the high enzyme treated wines as determined from the winemaker panel. Furthermore, the winemaker panel found acidity the only aroma or flavor descriptor significant in the high dosage ANOVA results. Whereas six descriptors in the low enzyme ANOVA results were significant in separating aroma and flavor samples. Except for Lallzyme EX (Lallemand) treated wine, the hunter colorimeter results showed all low enzyme treated wines were significantly (p<0.05) more red-purple (lower hues) than the high enzyme treated wines. / Graduation date: 1999

Thesis (M.S.)--California Polytechnic State University, 2009. / Title from PDF title page; viewed on February 3, 2010. Major professor: W. Keith Patterson, Ph.D. "Presented to the faculty of California Polytechnic State University, San Luis Obispo." "In partial fulfillment of the requirements for the degree [of] Master of Science in Agriculture." "November 2009." Includes bibliographical references (p. 68-70).

Thesis (M. Appl. Sc.) -- Lincoln University, 2007. / "A trial established in 2003 at Upper Moutere in Nelson, New Zealand, was used to evaluate the effect of mussel shells as reflective mulch on Vitis vinifera L. cv. Pinot noir vine performance and fruit and wine quality"--Abstract. Also available via the World Wide Web.

Thesis (M.S.)--Michigan State University. Dept. of Horticulture, 2006. / Title from PDF t.p. (viewed on June 19, 2009) Includes bibliographical references (p. 161-168). Also issued in print.

A three-year study was conducted at a commercial vineyard site in California’s Edna Valley AVA to evaluate the physiological and agronomical effects of the timing of cluster thinning on Pinot noir (clone 115) grapevines. Vines were thinned to one cluster per shoot at three selected time-points during the growing season (bloom, bloom + 4 weeks, bloom + 8 weeks), and fruit from each treatment was harvested and made into wine. Across all growing seasons, yield decreased 43% in thinned vines relative to un-thinned control vines. No effect of cluster thinning or interaction with growing season was found in vine shoot diameter, internode length, fruit zone light level, or cluster weight. Growing season significantly affected more fruit and wine parameters than did cluster thinning treatment, with interactions between treatment and growing season found in fruit Brix, titratable acidity, and anthocyanins, as well as wine anthocyanins and wine b* (yellow component). For example, bloom + 8 and bloom + 12 thinning treatments advanced Brix in 2017 but had no effect in 2018. Cluster thinning treatments increased berry anthocyanins by 43% in 2017 and by 103% in 2018 relative to the control. Similarly, cluster thinning increased berry total phenolics by 87% in 2017 and by 140% in 2018 relative to the control, with no significant differences found between the different thinning treatments. However, the levels of anthocyanins and total phenolics were generally not affected by cluster thinning treatment in the resulting wines. The fact that different cluster thinning treatments resulted in nil or minor effects on fruit and wine suggests that the vines tested were at or below a balanced crop load prior to the application of cluster thinning. Edna Valley AVA could likely support higher crop loads than 3.2 on the Ravaz index without negatively impacting fruit or wine composition and reducing crop load below that level is unlikely to increase fruit or wine quality.