Over the last several years many Oregon winemakers have expressed concerns over the frequency of 'stuck' and sluggish yeast fermentations. These problems are probably due to low nitrogen status of musts at harvest. Malolactic fermentations may also be affected by low levels of fermentable nitrogen in juice and wine. Low...
The objectives of this study are to evaluate the effects of manipulating soil moisture and nitrogen availability using different approaches, including supplemental irrigation, nitrogen addition to the soil or to the leaves, and the elimination of competition for water and nutrients between the ground cover and the grapevines by tilling....
Several macerating pectinase enzyme preparations are currently being used by Oregon wineries to enhance color, color stability and phenolic extraction of red wines. Previous research on the use of commercial pectinase enzymes in Oregon Pinot noir and Cabernet Sauvignon wines showed that some enzyme preparations were capable of reducing red...
Commercial fermentation practices have been evaluated for several vintages to determine their effects on anthocyanin and phenolic extraction, wine color intensity, color stability, and sensory characteristics of Oregon Pinot noir wines. Trials have included fermentation processing practices (1994), the use of different commercial yeast strains (1995 and 1996), the addition...
During the 1994, 1995, and 1996 vintages we designed a series of trials to evaluate the effects of commercial Pinot noir fermentation practices in Oregon on wine composition and quality. Differences have been observed in anthocyanin content, color intensity, polymeric pigment content, phenolic content, and in aroma, flavor, body, and...
An approximation of the total yeast fermentable nitrogen content in juice or must is taken as the sum of the nitrogen available from ammonia and the alpha-amino acids present (Bisson 1991 ; Dukes and Butzke 1998 ; Jiranek, Langridge, and Henshcke 1995). Recommended levels of fermentable nitrogen needed by yeast...
Winemakers commonly attribute differences in color, color stability, and phenolic composition to different fermentation practices. The extraction of anthocyanin pigments and other phenolic compounds from the skins, pulp, seeds, and stems to a large degree determines the composition and quality of red wines.
During the 1994 vintage we designed a...
A new general method is developed for the optimization of
HPLC ternary or pseudo-quaternary mobile phases which are
represented by the trilinear coordinate system. This method can
predict the global optimum of the mobile phase composition. The
global optimum composition along each edge of the triangle and
the corresponding selectivity...
One of the motives of China's Economic Reform is to bring Western
management techniques to China to further economic development. The miraculous
success of the Special Economic Zone (SEZ) in Shenzhen, Guangdong has attracted
many foreign investors who gladly bring their management expertise. This thesis looks
at small, medium and...
The Machine Learning (ML) algorithms are increasingly explored in varies of fields including designing and optimizing computer systems. Recent research, such as optimizing memory/cache prefetching by ML training or predicting traffic pattern in throughput processors, also exhibits a promising future of introducing ML into computer system design and optimization. Throughput...