Browsing Masters Degrees (Institute for Wine Biotechnology) by Title
Now showing items 34-53 of 54
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Lactobacillus plantarum : amino acid utilization
(Stellenbosch : Stellenbosch University, 2018-03)ENGLISH ABSTRACT: Amino acid metabolism serves as a source of sulphur, carbon and nitrogen for bacteria growing in wine or grape juice. The metabolism of amino acids controls the rate of growth and malic acid degradation ... -
Linking the phenolic potential of grape berries with polyphenol distribution during wine making : a Sauvignon Blanc case study.
(Stellenbosch : Stellenbosch University, 2019-04)ENGLISH ABSTRACT: The focus of this study was the phenolic potentials of grape and wine matrices of Sauvignon Blanc produced in either a high or low light microclimate. Phenolic compounds are important in grapes due to ... -
Manipulating the levels of ethyl acetate and isoamyl acetate formation during the production of wine and brandy
(Stellenbosch : Stellenbosch University, 2002-12)ENGLISH ABSTRACT: The production of wine is a complex process, which involves the conversion of sugar in grape must to ethanol, carbon dioxide and other byproducts. The principal organism in winemaking is yeast, of which ... -
A microbiological solution to visible wine defects : pinking and protein haze formation
(Stellenbosch : Stellenbosch University, 2019-04)ENGLISH ABSTRACT: The wine industry is challenged with visible and nonvisible wine defects, which result in profit losses as consumers reject such wines. The clarity and color of the wine are essential to white wine ... -
Molecular typing of wine yeasts : evaluation of typing techniques and establishment of a database
(Stellenbosch : Stellenbosch University, 2012-03)ENGLISH ABSTRACT: The yeast species, Saccharomyces cerevisiae and S. bayanus are well known for the key role they play during alcoholic fermentation in both wine and beer industries. These yeasts are available in pure ... -
Mss11p mediated regulation of transcription, pseudohyphal differentiation and flocculation in Saccharomyces cerevisiae
(Stellenbosch : Stellenbosch University, 2004-03)ENGLISH ABSTRACT: In all cellular systems the ability to alter eellular programs in response to extracellular cues is essential for survival. This involves the integration of signals triggered by membrane bound receptors ... -
Multispecies interactions in a simplified wine yeast consortium
(Stellenbosch : Stellenbosch University, 2018-03)ENGLISH ABSTRACT: Over the last two decades various studies have evaluated the impact of non-Saccharomyces (NS) yeasts on alcoholic fermentation of wine, the chemical imprint they leave in the wine and how this affects ... -
Network-based contextualisation of LC-MS/MS proteomics data
(Stellenbosch : Stellenbosch University, 2014-12)ENGLISH ABSTRACT: This thesis explores the use of networks as a means to visualise, interpret and mine MS-based proteomics data. A network-based approach was applied to a quantitative, cross-species LCMS/ MS dataset ... -
Optimization of β-glucosidase activy in recombinant Saccharomyces cerevisiae strains
(Stellenbosch : Stellenbosch University, 2007-12)ENGLISH ABSTRACT: Wine is a complex medium. Wine aroma, flavour and colour are important quality factors, but these can be influenced by many factors, such as grape-derived compounds that exist as free volatiles and also ... -
The production of resveratrol by wine yeast
(Stellenbosch : Stellenbosch University, 2001-03)ENGLISH ABSTRACT: Grapevine is constantly under attack from a wide variety of pathogens including viruses, bacteria and fungi. In order to ensure survival, the grapevine has developed a vast array of defense mechanisms ... -
The role of lactic acid bacteria in brandy production
(Stellenbosch : Stellenbosch University, 2002-12)ENGLISH ABSTRACT: The presence and growth of lactic acid bacteria (LAB) in wine and their influence on wine quality has received much attention in recent years. Lactic acid bacteria are responsible for conducting ... -
Some aroma compounds of importance to the quality of Ferdinand de Lesseps and Kerner wines
(Stellenbosch : Stellenbosch University, 2000-03)ENGLISH ABSTRACT: Ferdinand de Lesseps grapes have a distinctive fruity varietal character and were often used judiciously by wine-makers to enhance the fruity bouquet of some white table wines. Ferdinand de Lesseps ... -
Sources of acetic and other fatty acids and their role in sluggish and stuck red wine fermentations
(Stellenbosch : Stellenbosch University, 2000-04)ENGLISH ABSTRACT: The quality of wine is influenced by numerous factors. These factors include the quality of the grapes, winemaking techniques and quality control throughout the winemaking process. It is thus very ... -
Stationary phase-specific expression of dominant flocculation genes for controlled flocculation of yeast
(Stellenbosch : Stellenbosch University, 2003-04)ENGLISH ABSTRACT: Flocculation can be defined as the asexual aggregation of yeast cells in a liquid environment. This aggregation of cells, also referred to as "floc formation", will in most cases lead to rapid settling ... -
Stress, fermentation performance and aroma production by yeast
(Stellenbosch : Stellenbosch University, 2012-03)ENGLISH ABSTRACT: Yeast strains contend with numerous stresses during winemaking. An inability to perceive and initiate the physiological changes needed to adapt to stress, has been linked to slow or incomplete (residual ... -
A study of within-vineyard variability with conventional and remote sensing technology
(Stellenbosch : Stellenbosch University, 2003-12)ENGLISH ABSTRACT: In the past it was very difficult to visualise the extent and distribution of variability in growth vigour within vineyards. The advancement of remote sensing technology has changed this however, ... -
A survey of the YAN status of South African grape juices and exploration of multivariate data analysis techniques for spectrometric calibration and cultivar discrimination purposes.
(Stellenbosch : Stellenbosch University, 2018-12)ENGLISH ABSTRACT: Yeast assimilable nitrogen (YAN) has been identified as one of the main drivers of wine quality, influencing the production of various aromas and ensuring a successful fermentation to dryness. Due to the ... -
The transformation of wine yeasts with glucanase, xylanase and pectinase genes for improved clarification and filterability of wine
(Stellenbosch : Stellenbosch University, 2003-03)ENGLISH ABSTRACT: Cellulose is by far the most abundant carbohydrate available from plant biomass. These biopolymers are therefore an important renewable source of food, fuels and chemicals. Cellulose is embedded in a ... -
Understanding South African Chenin Blanc wine by using data mining techniques applied to published sensory data
(Stellenbosch : Stellenbosch University, 2016-03)ENGLISH ABSTRACT: South African Chenin Blanc is the most planted grape cultivar in South Africa (SA) and is known for its versatility in wine sensory profiles. However, according to the South African wine industry, consumers ... -
The use of technology to improve current precision viticulture practices: predicting vineyard performance
(Stellenbosch : Stellenbosch University, 2018-12)ENGLISH ABSTRACT: Producing high quality grapes is difficult due to intra-vineyard spatial variability in vineyards. Variability leads to differences in grape quality and quantity. This poses a problem for producers, as ...
