Tannins are classified as flavonoids and non-flavonoids. Non-flavonoids consist of gallic acid, e... more Tannins are classified as flavonoids and non-flavonoids. Non-flavonoids consist of gallic acid, ellagic acid, hydroxycinnamic acid and hydroxybenzoic acid and their derivatives. Flavonoids consist of flavonols, flavan-3-ols, flavan-3,4-ols and anthocyanins. Tannins are also known as the phenolic composition of the wine, total polyphenols or wine phenols.
Across the globe, academic staff members of accredited tertiary education institutions are expect... more Across the globe, academic staff members of accredited tertiary education institutions are expected to perform tasks pertaining to teaching and learning, research, and community engagement. Particularly in a South African dispensation, research shows that many accredited tertiary education institutions’ academic staff members have excessive teaching and learning workloads which, in turn, adversely affect their research productivity – their abilities to publish research outputs (e.g. articles, conference papers, and books). It should be noted that for every accredited research output produced by a South African accredited tertiary education institution, it is entitled to subsidy income from the Department of Higher Education and Training. Regardless of the foregoing, there is a reported decline in research productivity of South African accredited tertiary education institution academic staff members. As such, for this study, the phenomenon of Research Collaboration and Networking (RE...
The notion that more anthocyanins may be obtained through a prealcoholic maceration is widely hel... more The notion that more anthocyanins may be obtained through a prealcoholic maceration is widely held. This concept dates from the mid 1980s when it was first applied by a Lebanese winemaker, a certain Guy Accad, to Pinot noir. His contention, that cold maceration would extract more colour from Pinot noir, was apparently correct. The question then arose whether it would apply to all cultivars.
An encounter with the words monopigments or polymeric pigments leads one to wonder what they mean... more An encounter with the words monopigments or polymeric pigments leads one to wonder what they mean exactly. Tannins are divided into two basic groups, namely the flavonoids and the non-flavonoids. The non-flavonoids consist of gallic acid, ellagic acid, hydroxycinnamic acid and hydroxybenzoic acid and their derivatives. Flavonoids consist of flavonols, flavan-3-ols, flavan-3,4-ols and anthocyanins.
Tannins consist of a set of monomers named catechins, epicatechins, epigallocatechins and epicate... more Tannins consist of a set of monomers named catechins, epicatechins, epigallocatechins and epicatechin-gallate. These monomers occur in different polymeric lengths in the skin andseed of the grape berry. There is also a difference in the composition of monomers between skin tannins and seed tannins. Only seed tannins contain epicatechingallate.
Pienking is ’n fenomeen wat ontstaan sodra witwyne wat diepotensiaal het om te pienk aan suurstof... more Pienking is ’n fenomeen wat ontstaan sodra witwyne wat diepotensiaal het om te pienk aan suurstof blootgestel word. Ditkom algemeen in Sauvignon blanc voor, maar ook in Chardonnay, Colombar, Chenin blanc en Viognier.
In die wingerdseksie van Elsenburg staan 'n blokkie onderstokke (wingerd waarop wynkultivars ... more In die wingerdseksie van Elsenburg staan 'n blokkie onderstokke (wingerd waarop wynkultivars geent word) waarvan slegs sommige se name bekend is, maar wat maak hierdie blok so spesiaal en waarom moet dit vir die nageslag bewaar word? Behalwe vir die feit dat dit reeds 76 jaar oud is, le die werklike waarde daarvan in die rede waarom dit gedoen is. Die idee daaragter was om 'n moederblok van onderstokke te plant sodat indien daar weer iets verkeerd loop in die Suid-Afrikaanse wynbedryf, daar 'n blok sou wees om op terug te val. Om die rede agter dit te verstaan is dit belangnk om eers terug te gaan in die geskiedenis.
The objective of this study was to investigate the mouthfeel ofShiraz wines with the accompanying... more The objective of this study was to investigate the mouthfeel ofShiraz wines with the accompanying chemical compounds. Thedifference between the mouthfeel of two wines from differentclimatic zones, as well as two different ripeness levels, was also investigated. The outcome of the investigation may shed light on the effect of different winemaking techniques on the mouthfeel of wine.
In die wingerdseksie van Elsenburg staan 'n blokkie onderstokke (wingerd waarop wynkultivars ... more In die wingerdseksie van Elsenburg staan 'n blokkie onderstokke (wingerd waarop wynkultivars geent word) waarvan slegs sommige se name bekend is, maar wat maak hierdie blok so spesiaal en waarom moet dit vir die nageslag bewaar word? Behalwe vir die feit dat dit reeds 76 jaar oud is, le die werklike waarde daarvan in die rede waarom dit gedoen is. Die idee daaragter was om 'n moederblok van onderstokke te plant sodat indien daar weer iets verkeerd loop in die Suid-Afrikaanse wynbedryf, daar 'n blok sou wees om op terug te val. Om die rede agter dit te verstaan is dit belangnk om eers terug te gaan in die geskiedenis.
Tannins are classified as flavonoids and non-flavonoids. Non-flavonoids consist of gallic acid, e... more Tannins are classified as flavonoids and non-flavonoids. Non-flavonoids consist of gallic acid, ellagic acid, hydroxycinnamic acid and hydroxybenzoic acid and their derivatives. Flavonoids consist of flavonols, flavan-3-ols, flavan-3,4-ols and anthocyanins. Tannins are also known as the phenolic composition of the wine, total polyphenols or wine phenols. A wide variety of methods may be used to analyse wine for phenols. These methods range from simple to complex. There are three principal methods to analyse for phenols or tannins. These methods are the colorimetric, gravimetric and precipitation assays. As early as 1912, Otto Folin and W. Denis started developing a method to analyse the total phenols of wine. In 1927, Otto Folin and Vintila Ciocaltue adapted the original Folin-Denis to improve analysis of total phenols. To this day it is known as the Folin-Ciocaltue method. It is a long method that takes almost three hours and is read at 765 nm on a spectrophotometer. In 1978, Calif...
In 1864 - 1865 a then unknown insect started attacking French vineyards. The cause of the destruc... more In 1864 - 1865 a then unknown insect started attacking French vineyards. The cause of the destruction of the vineyards was shrouded in mystery, due to the fact that the leaves developed strange galls, where after they perished. The losses, as a result of phylloxera, were so severe that a commission to combat the new disease of the grapevine (La Commission pour Combattre la Nouvelle Maladie de la Vigne) was founded by the Herault Agricultural Society in the spring of 1868. On 3 August 1868 Jules-Emile Planchon declared it to be an insect.
Across the globe, academic staff members of accredited tertiary education institutions are expect... more Across the globe, academic staff members of accredited tertiary education institutions are expected to perform tasks pertaining to teaching and learning, research, and community engagement. Particularly in a South African dispensation, research shows that many accredited tertiary education institutions’ academic staff members have excessive teaching and learning workloads. This, in turn, adversely affects their research productivity - their abilities to publish research outputs (e.g. articles, conference papers, and books). It should be noted that for every accredited research output produced by a South African accredited tertiary education institution, the institution is entitled to subsidy income from the Department of Higher Education and Training. Regardless of the foregoing, there is a reported decline in research productivity of accredited South African tertiary education institutions’ academic staff members. As such, for this study, the phenomenon of Research Collaboration an...
The objective of this study was to determine the effect of ripeness and of different tannin extra... more The objective of this study was to determine the effect of ripeness and of different tannin extraction methods on the sensory properties of wine, with a specific focus on mouthfeel properties. Quantitative descriptive analysis (QDA) was performed to evaluate the sensory properties of 20 young Shiraz wines in two phases. In Phase 1, wines from a cool area were evaluated and, in Phase 2, wines from a warm area were evaluated. Clear differences were found between the wines from the two regions. Wines from the cooler region were generally associated with higher levels of total non-flavonoids and total anthocyanins, and more intense numbing and puckering sensations. In contrast, the wines from the warmer region as a group were associated with a more drying and grippy mouthfeel, as well as less total anthocyanins and total non-flavonoids. In the set of wines from the cooler region, the effect of ripeness was more pronounced than in the set of wines from the warmer region. In both cases, r...
In 2012 is daar besluit om lidmaatskap by BWI (Biodiversiteit en Wyn Inisiatief) te bekom. 'n... more In 2012 is daar besluit om lidmaatskap by BWI (Biodiversiteit en Wyn Inisiatief) te bekom. 'n Inskrywingsvorm is aangevra en deurgelees. Een van BWI se vereistes is dat 'n stuk grond, verkieslik groter as 4ha, vir bewaringsdoeleindes beskikbaar gestel word. Grond wat aan die Kromme Rhee pad grens het dadelik in die gedagte opgekom.
Tannins are classified as flavonoids and non-flavonoids. Non-flavonoids consist of gallic acid, e... more Tannins are classified as flavonoids and non-flavonoids. Non-flavonoids consist of gallic acid, ellagic acid, hydroxycinnamic acid and hydroxybenzoic acid and their derivatives. Flavonoids consist of flavonols, flavan-3-ols, flavan-3,4-ols and anthocyanins. Tannins are also known as the phenolic composition of the wine, total polyphenols or wine phenols.
Across the globe, academic staff members of accredited tertiary education institutions are expect... more Across the globe, academic staff members of accredited tertiary education institutions are expected to perform tasks pertaining to teaching and learning, research, and community engagement. Particularly in a South African dispensation, research shows that many accredited tertiary education institutions’ academic staff members have excessive teaching and learning workloads which, in turn, adversely affect their research productivity – their abilities to publish research outputs (e.g. articles, conference papers, and books). It should be noted that for every accredited research output produced by a South African accredited tertiary education institution, it is entitled to subsidy income from the Department of Higher Education and Training. Regardless of the foregoing, there is a reported decline in research productivity of South African accredited tertiary education institution academic staff members. As such, for this study, the phenomenon of Research Collaboration and Networking (RE...
The notion that more anthocyanins may be obtained through a prealcoholic maceration is widely hel... more The notion that more anthocyanins may be obtained through a prealcoholic maceration is widely held. This concept dates from the mid 1980s when it was first applied by a Lebanese winemaker, a certain Guy Accad, to Pinot noir. His contention, that cold maceration would extract more colour from Pinot noir, was apparently correct. The question then arose whether it would apply to all cultivars.
An encounter with the words monopigments or polymeric pigments leads one to wonder what they mean... more An encounter with the words monopigments or polymeric pigments leads one to wonder what they mean exactly. Tannins are divided into two basic groups, namely the flavonoids and the non-flavonoids. The non-flavonoids consist of gallic acid, ellagic acid, hydroxycinnamic acid and hydroxybenzoic acid and their derivatives. Flavonoids consist of flavonols, flavan-3-ols, flavan-3,4-ols and anthocyanins.
Tannins consist of a set of monomers named catechins, epicatechins, epigallocatechins and epicate... more Tannins consist of a set of monomers named catechins, epicatechins, epigallocatechins and epicatechin-gallate. These monomers occur in different polymeric lengths in the skin andseed of the grape berry. There is also a difference in the composition of monomers between skin tannins and seed tannins. Only seed tannins contain epicatechingallate.
Pienking is ’n fenomeen wat ontstaan sodra witwyne wat diepotensiaal het om te pienk aan suurstof... more Pienking is ’n fenomeen wat ontstaan sodra witwyne wat diepotensiaal het om te pienk aan suurstof blootgestel word. Ditkom algemeen in Sauvignon blanc voor, maar ook in Chardonnay, Colombar, Chenin blanc en Viognier.
In die wingerdseksie van Elsenburg staan 'n blokkie onderstokke (wingerd waarop wynkultivars ... more In die wingerdseksie van Elsenburg staan 'n blokkie onderstokke (wingerd waarop wynkultivars geent word) waarvan slegs sommige se name bekend is, maar wat maak hierdie blok so spesiaal en waarom moet dit vir die nageslag bewaar word? Behalwe vir die feit dat dit reeds 76 jaar oud is, le die werklike waarde daarvan in die rede waarom dit gedoen is. Die idee daaragter was om 'n moederblok van onderstokke te plant sodat indien daar weer iets verkeerd loop in die Suid-Afrikaanse wynbedryf, daar 'n blok sou wees om op terug te val. Om die rede agter dit te verstaan is dit belangnk om eers terug te gaan in die geskiedenis.
The objective of this study was to investigate the mouthfeel ofShiraz wines with the accompanying... more The objective of this study was to investigate the mouthfeel ofShiraz wines with the accompanying chemical compounds. Thedifference between the mouthfeel of two wines from differentclimatic zones, as well as two different ripeness levels, was also investigated. The outcome of the investigation may shed light on the effect of different winemaking techniques on the mouthfeel of wine.
In die wingerdseksie van Elsenburg staan 'n blokkie onderstokke (wingerd waarop wynkultivars ... more In die wingerdseksie van Elsenburg staan 'n blokkie onderstokke (wingerd waarop wynkultivars geent word) waarvan slegs sommige se name bekend is, maar wat maak hierdie blok so spesiaal en waarom moet dit vir die nageslag bewaar word? Behalwe vir die feit dat dit reeds 76 jaar oud is, le die werklike waarde daarvan in die rede waarom dit gedoen is. Die idee daaragter was om 'n moederblok van onderstokke te plant sodat indien daar weer iets verkeerd loop in die Suid-Afrikaanse wynbedryf, daar 'n blok sou wees om op terug te val. Om die rede agter dit te verstaan is dit belangnk om eers terug te gaan in die geskiedenis.
Tannins are classified as flavonoids and non-flavonoids. Non-flavonoids consist of gallic acid, e... more Tannins are classified as flavonoids and non-flavonoids. Non-flavonoids consist of gallic acid, ellagic acid, hydroxycinnamic acid and hydroxybenzoic acid and their derivatives. Flavonoids consist of flavonols, flavan-3-ols, flavan-3,4-ols and anthocyanins. Tannins are also known as the phenolic composition of the wine, total polyphenols or wine phenols. A wide variety of methods may be used to analyse wine for phenols. These methods range from simple to complex. There are three principal methods to analyse for phenols or tannins. These methods are the colorimetric, gravimetric and precipitation assays. As early as 1912, Otto Folin and W. Denis started developing a method to analyse the total phenols of wine. In 1927, Otto Folin and Vintila Ciocaltue adapted the original Folin-Denis to improve analysis of total phenols. To this day it is known as the Folin-Ciocaltue method. It is a long method that takes almost three hours and is read at 765 nm on a spectrophotometer. In 1978, Calif...
In 1864 - 1865 a then unknown insect started attacking French vineyards. The cause of the destruc... more In 1864 - 1865 a then unknown insect started attacking French vineyards. The cause of the destruction of the vineyards was shrouded in mystery, due to the fact that the leaves developed strange galls, where after they perished. The losses, as a result of phylloxera, were so severe that a commission to combat the new disease of the grapevine (La Commission pour Combattre la Nouvelle Maladie de la Vigne) was founded by the Herault Agricultural Society in the spring of 1868. On 3 August 1868 Jules-Emile Planchon declared it to be an insect.
Across the globe, academic staff members of accredited tertiary education institutions are expect... more Across the globe, academic staff members of accredited tertiary education institutions are expected to perform tasks pertaining to teaching and learning, research, and community engagement. Particularly in a South African dispensation, research shows that many accredited tertiary education institutions’ academic staff members have excessive teaching and learning workloads. This, in turn, adversely affects their research productivity - their abilities to publish research outputs (e.g. articles, conference papers, and books). It should be noted that for every accredited research output produced by a South African accredited tertiary education institution, the institution is entitled to subsidy income from the Department of Higher Education and Training. Regardless of the foregoing, there is a reported decline in research productivity of accredited South African tertiary education institutions’ academic staff members. As such, for this study, the phenomenon of Research Collaboration an...
The objective of this study was to determine the effect of ripeness and of different tannin extra... more The objective of this study was to determine the effect of ripeness and of different tannin extraction methods on the sensory properties of wine, with a specific focus on mouthfeel properties. Quantitative descriptive analysis (QDA) was performed to evaluate the sensory properties of 20 young Shiraz wines in two phases. In Phase 1, wines from a cool area were evaluated and, in Phase 2, wines from a warm area were evaluated. Clear differences were found between the wines from the two regions. Wines from the cooler region were generally associated with higher levels of total non-flavonoids and total anthocyanins, and more intense numbing and puckering sensations. In contrast, the wines from the warmer region as a group were associated with a more drying and grippy mouthfeel, as well as less total anthocyanins and total non-flavonoids. In the set of wines from the cooler region, the effect of ripeness was more pronounced than in the set of wines from the warmer region. In both cases, r...
In 2012 is daar besluit om lidmaatskap by BWI (Biodiversiteit en Wyn Inisiatief) te bekom. 'n... more In 2012 is daar besluit om lidmaatskap by BWI (Biodiversiteit en Wyn Inisiatief) te bekom. 'n Inskrywingsvorm is aangevra en deurgelees. Een van BWI se vereistes is dat 'n stuk grond, verkieslik groter as 4ha, vir bewaringsdoeleindes beskikbaar gestel word. Grond wat aan die Kromme Rhee pad grens het dadelik in die gedagte opgekom.
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