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Právní ochrana spotřebitele se zaměřením na reklamu a regulaci užívání alkoholických nápojů / The legal protection of the consumer focused on regulation of alcoholic beverages advertising and usagePekárek, Kamil January 2012 (has links)
Thesis deals with problems in legal as well as non legal regulations of alcohol usage in Czech Republic. I analyse the development of laws and current version of legal regulations on alcohol availability for young people in Czech Republic. I compare the Czech legislative to legislative in other countries. I analyse different approach to alcohol drinking in varied societies. During work on the diploma thesis, the Czech government declared a prohibition on alcohol trade. I evaluate the Czech approach and compare this prohibition with prohibitions in other countries. Finally, I evaluate Czech regulations of alcohol advertisments, and describe several court decisions (and self-regulatory board decisions) in alcohol advertising. The aim of thesis is to find the positive and negative aspects of legal and non-legal regulations in individual countries and propose new solutions to current alcohol problems.
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Exploiting Sexual Dimorphism in Liver Disease: Targeting Sex Hormone Signaling to Treat Non-Alcoholic Fatty Liver Disease and Hepatocellular CarcinomaHelms, Timothy H. January 2021 (has links)
No description available.
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Hur mår en individ som är medberoende till en anhörig med alkoholmissbruk? Vilken hjälp finns i samhället för dem? : En strukturerad litteraturstudie / How do people codependent with those suffering from alcohol abuse feel? And what help is available for them? : A structured reviewHenriksson, Malin, Rönning Adolfsson, Linn January 2022 (has links)
Bakgrund: Alkoholberoende är ett missbruk som klassas som sjukdom av WHO och innebär psykiskt lidande för den drabbade och dennes anhöriga. Att vara närbesläktad med en alkoholberoende klassas som medberoende och det betyder inte att de dricker alkohol eller missbrukar själva men risken att drabbas finns om det nedärvda beteendet finns hos barnen. Fjorton procent av Sveriges befolkning räknas med att vara anhörig till en person som dricker för mycket. Alkoholnäringen i Sverige drar in 10 miljarder i vinst varje år men baksidan kostar mer, brottsbekämpningen, vården och produktionsbortfall kostar 103 miljarder svenska kronor om året. Syfte: Hur alkoholmissbruk påverkar den psykiska hälsan hos anhöriga/medberoende och vilka rättigheter och hjälp de har från samhället. Metod: Studien bygger på en litteraturstudie som analyserats med en tematisk analys där vetenskapliga artiklar granskats, identifieras och beskriver det insamlade datamaterialet för att få svar på syftet. Databasen som användes var Pubmed från Högskolan i Skövdes webbplats. Resultat: Resultaten visades i tre huvudkategorier; psykologiska aspekter, medberoende och hjälp i samhället. Fem teman togs ut; beteendeförändringar och copingstrategier, personlighetsdrag och känslor, psykiskt välbefinnande, familjesituation och relationer samt socialt- och externt stöd. Slutsats: Resultatet visar att många medberoende i nära relation till en alkoholmissbrukare lider av psykisk ohälsa och att det leder till stora hälsorisker i samband med levnadsvanorna. Det finns hjälp att få då både psykisk ohälsa samt alkoholmissbruk är två stora samhällsproblem, men det är ett folkhälsoproblem som kräver ännu tydligare riktlinjer från primärvården i Sverige. / Background: Alcohol dependence is an addiction that is classified as a disease by WHO and involves mental suffering for the victim and his or her relatives. Being closely related to an alcohol addict is classified as co-addicted and this does not mean that they drink alcohol or abuse themselves, but the risk of being affected exists if the inherited behavior is present in the children. Fourteen percent of Sweden's population is considered to be related to a person who drinks too much. The alcohol industry in Sweden makes a profit of SEK 10 billion every year, but the downside costs more, law enforcement, healthcare and loss of production cost SEK 103 billion a year. Purpose: How alcohol abuse affects the mental health of relatives. Method: The study is based on a literature study and athematic analysis in which scientific articles are reviewed, identified and describes the collected data material to get answers to the purpose. The database Pubmed were used from the University of Skövde's website. Results: The results were shown in three main categories; psychological aspects, co-dependence and help in society. Five themes were taken out; behavioral changes and coping strategies, personality traits and emotions, mental well-being, family situation and relationships as well as social and external support. Conclusion: The results show that many co-addicts in a close relationship with an alcohol addict feel mentally ill and that it leads to major health risks in connection with living habits. Mental illness and alcohol abuse are two big public health problems and it requires even more guidelines from primary care in Sweden.
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Essays in applied demand and production analysisZereyesus, Yacob Abrehe January 1900 (has links)
Doctor of Philosophy / Department of Agricultural Economics / Vincent R. Amanor-Boadu / This dissertation is composed of two essays in applied microeconomics. Using farm level data, the first essay applied nonparametric methods to test the adherence of individual farm’s production choices to profit maximization objective. Results indicate that none of the farms consistently satisfy the joint hypothesis of profit maximization. The study took into account the uncertainty prevalent in agricultural production by systematically modeling the optimization behavior of farms. Departures of observed data of individual farms from profit maximization objectives were attributed more due to stochastic influences caused by output production decisions than input use decisions. Results also support the existence of technological progress during the study period for Kansas farms. At an alpha level of 5%, assuming both input and output quantities as stochastic, only 5.3% of the farms violated the joint hypothesis of profit maximization with standard error exceeding 10%. Whereas when only input quantities are considered stochastic, a total of 71.73% and 2.09% of the farms had minimum standard errors of greater than 10% and 20% respectively required for the joint profit maximization hypothesis to hold. When only output quantity measurements were assumed as stochastic, a total of 80.10 % and 18.84 % of the farms had minimum standard errors of greater than 10% and 20% respectively required for the profit maximization hypothesis to hold.
The second essay examines the demand for alcoholic beverages (beer, wine and distilled spirits) for the U.S. using time series data from 1979-2006. The estimation is done using an error correction form of the Almost Ideal Demand System . Results indicate that there is a significant difference between short run and long run elasticity estimates. The paper addresses the exogeneity of log of prices and log of real expenditures. For the beer and wine equations, the hypothesis of joint exogeneity of price index and real expenditure cannot be rejected at all the
conventional levels of significance. For the spirits equation, the tests strongly reject the simultaneous exogeneity of price index and real expenditure. When independently tested, price index appears to be endogenous variable where as real expenditure seems exogenous variable. Based on these results, the real expenditure was considered as an exogenous variable, where as the price index for spirits as an endogenous variable.
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Social grant recipient spending on sin taxed items / A.D. PietersenPietersen, Ashley Deon January 2014 (has links)
Sin taxes have increased significantly during the past three years. There have been different opinions regarding the levying of sin taxes: in relation to whether it helps the government to raise revenue or reduces the consumption thereof. This study therefore investigates the actual purpose for these taxes by means of a literature and empirical review. An increase in sin taxes affects the poor more than the rich because such taxes are classified as a regressive type of tax. The primary research problem addressed by this literature study was to determine the percentage that the lower income earning group of South African citizens, who are funded by social grants, spend on sin taxed items. This study focused on two areas: the social grant system in conjunction with the Consumer Price Index (“CPI”) and the levying of sin taxes in South Africa. Over the years, South Africa has experienced an increase in its levels of poverty. There are eight types of social grants in South Africa, to which the lower income earning South African citizens, who live below the poverty line, are entitled, depending on their circumstances. This study discusses only seven of the eight social grants, by considering the purpose of the social grant, criteria, means testing requirements and the monthly amount available. These grants include the child support grant, old age grant, disability grant, foster care grant, care dependency grant, grant-in-aid and war veteran grant. The CPI of South Africa is briefly addressed in this study, followed by the increases over the past three years. The escalations of the social grants and that of the CPI of South Africa have been compared in order to determine whether the government remains concerned for their lower income earning citizens most of whom live below the poverty line. For purposes of this study, sin taxes have been narrowed down to include only alcoholic beverages and cigarettes. This study determined the increases of sin taxes on these substances over the past three years as well as the consumption thereof. Their consumption was determined by the sales volume. A comparison of the increases and consumption was made, the purpose of which was to determine government’s motivation for these increases. The empirical review of this study investigated the social grant recipients’ spending habits on these items. This was done by means of a self- developed questionnaire. The purpose of the questionnaire was to determine the percentage of their grant money that the social grant recipients spend on alcoholic beverages and cigarettes. The results and findings led to a conclusion which addressed the problem of this study. This study makes recommendations for further investigation of the sin tax implications for the lower income earning South African citizens, who are funded by social grants. / MCom (Accountancy)--North-West University, Vaal Triangle Campus, 2015
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Social grant recipient spending on sin taxed items / A.D. PietersenPietersen, Ashley Deon January 2014 (has links)
Sin taxes have increased significantly during the past three years. There have been different opinions regarding the levying of sin taxes: in relation to whether it helps the government to raise revenue or reduces the consumption thereof. This study therefore investigates the actual purpose for these taxes by means of a literature and empirical review. An increase in sin taxes affects the poor more than the rich because such taxes are classified as a regressive type of tax. The primary research problem addressed by this literature study was to determine the percentage that the lower income earning group of South African citizens, who are funded by social grants, spend on sin taxed items. This study focused on two areas: the social grant system in conjunction with the Consumer Price Index (“CPI”) and the levying of sin taxes in South Africa. Over the years, South Africa has experienced an increase in its levels of poverty. There are eight types of social grants in South Africa, to which the lower income earning South African citizens, who live below the poverty line, are entitled, depending on their circumstances. This study discusses only seven of the eight social grants, by considering the purpose of the social grant, criteria, means testing requirements and the monthly amount available. These grants include the child support grant, old age grant, disability grant, foster care grant, care dependency grant, grant-in-aid and war veteran grant. The CPI of South Africa is briefly addressed in this study, followed by the increases over the past three years. The escalations of the social grants and that of the CPI of South Africa have been compared in order to determine whether the government remains concerned for their lower income earning citizens most of whom live below the poverty line. For purposes of this study, sin taxes have been narrowed down to include only alcoholic beverages and cigarettes. This study determined the increases of sin taxes on these substances over the past three years as well as the consumption thereof. Their consumption was determined by the sales volume. A comparison of the increases and consumption was made, the purpose of which was to determine government’s motivation for these increases. The empirical review of this study investigated the social grant recipients’ spending habits on these items. This was done by means of a self- developed questionnaire. The purpose of the questionnaire was to determine the percentage of their grant money that the social grant recipients spend on alcoholic beverages and cigarettes. The results and findings led to a conclusion which addressed the problem of this study. This study makes recommendations for further investigation of the sin tax implications for the lower income earning South African citizens, who are funded by social grants. / MCom (Accountancy)--North-West University, Vaal Triangle Campus, 2015
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Strategic vision for the South African ready to drink marketSlabbert, Helgard 12 1900 (has links)
Thesis (MBA)--University of Stellenbosch, 2005. / ENGLISH ABSTRACT: The global RTD market was one of the fastest growing drinks categories in the world in 2002 and
many brewers and spirits companies have entered the new market. The RTD category gained
most of their volume from the young adult consumers and across the boundaries of wine. spirits
and beer. The strategic vision of the RID market determine whether this is a short intense fashion
or a permanent feature in the drinks market, given the historical precedence of the mid to late
1980's when the wine cooler boom and later the alcopops (alcoholic carbonates) phenomenon
passed as quickly as it came.
The purpose of the research report sets out to investigate the global RTD markets in order to
determine the strategic vision for the South African market. The study did a review of the top tcn
RID markets and then focussed on the strategies and performance of the Australian and United
Kingdom markets, due to the level of development and similarities in culture of these markets
with the South African market.
The analysis of the global RID markets showed the three successful RTD models are female,
androgynous and male RIDs and consumers perceived and use the three types of RTDs
differently.
Amongst the most important suggestions the author recommends that the biggest opportunity
for the South African R TD category is to gain market share from the beer market in the male
sector, which is by far the biggest seller of alcoholic beverages in South Africa. The current
successes in the South African market came from female and androgynous brands, but it is very
difficult to maintain brand loyalty within these segments due to the nature of the young adult
consumers and female drinkers. / AFRIKAANSE OPSOMMING: Die wereld gereed·om-te-drink (RTD) mark was een van die vinnigste groeiende drank
kategoriee in die wereld in 2002 en baie brouerye en spiritualieë maatskappye het tot die nuwe
mark toegetree. Die RTD kategorie het die meeste van sy volume verkry van die jong volwasse
verbruikers en van verskillende kategoriee soos wyn, spiritualieë en bier. Die strategiese visie van
die RTD mark bepaal of dit 'n gier of 'n permanente kenmerk in die drank mark is, soos
voorafgegaan van die middel tot laat 19805 toe die wyn verfrissers en later die "alcopops"
(alkoholiese karbonate) verskynsel so vinnig verdwyn het as wat dit gekom het.
Die doel van die navorsingsverslag is om die wereld RTD mark te ondersoek om 'n
strategiese visie vir die Suid-Afrikaanse mark te bepaal. Die navorsingstudie het die top tien RTD
markte ondersoek en toe gefokus op die strategiee en doeltreffendheid van die Australiese en
Verenigde Koninkrykte markte as gevolg van die vlak van ontwikkeling en ooreenkomste in
kulture van die markte met die Suid-Afrikaanse mark.
Die analise van die wereld RTD mark het getoon dat die drie suksesvolle vorme van RTDs is
vroue, tweeslagtige en mans RTDs en dat verbruikers verstaan en gebruik die drie tipes van
RTDs verskillend.
Van die belangrikste voorstelle wat die skrywer maak is dat die grootste geleendheid vir die Suid-Afrikaanse
RTDs is om mark aandeel van die bier kategorie in die mans sektor te verkry omdat
dit die grootste alkohol kategorie in Suid-Afrika is. Die huidige sukses in die Suid-Afrikaanse
mark het gekom van die vroue en tweeslagtige markte, maar dit is baie moeilik om die
verbruikers lojaal te hou vir die RTD produkte in die segmente as gevolg van die aard van die
jong volwasse verbruikers en vroue drinkers.
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Factors determining the progression of nonalcoholic fatty liver disease : the role of abnormal fatty acid and glucocorticoid metabolismMacFarlane, David Peter January 2011 (has links)
Obesity and insulin resistance are associated with a constellation of features including hypertension, dyslipidaemia, type 2 diabetes, and premature cardiovascular disease, collectively termed the metabolic syndrome. Non-alcoholic fatty liver disease (NAFLD) represents the hepatic component of this syndrome, incorporating a spectrum of liver disease with increasing morbidity and mortality, from simple steatosis, to non-alcoholic steatohepatitis (or NASH), fibrosis, cirrhosis and ultimately hepatocellular carcinoma. However, factors influencing this progression are incompletely understood. In this thesis I sought to investigate pathways which promote hepatic inflammation and fibrosis by studying two contrasting dietary models of NAFLD in mice in which the risk of hepatic inflammation, insulin resistance and fibrosis differ; namely the methionine and choline deficient diet (MCDD) which induces steatohepatitis, hepatic insulin resistance, and weight loss, and the choline deficient diet (CDD) which may be protected from insulin resistance, and leads to steatosis without inflammation or weight loss. I investigated the possible molecular mechanisms underlying these differences, and whether they influenced progression to hepatic fibrosis induced by carbon tetrachloride (CCl4).
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The use of enzymes for increased aroma formation in wineStidwell, Tanya Gwendryth 12 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: Monoterpene alcohols (monoterpenols) play an important role in the flavour and aroma of
grapes and wine. This is especially applicable to wines of a muscat variety, but these
flavour compounds are also present in other non-muscat grape varieties, where they
supplement other varietal flavours and aromas. These monoterpenols can be found in grapes and wine as free, volatile and odorous molecules, as well as in flavourless, nonvolatile
glycosidic complexes. These complexes most often occur as
6-0-a-L-arabinofuranosyl-p-D-glucopyranosides (vicianosides), 6-0-P-D-xylopyranosyl-
P-D-gluco-pyranosides (primverosides), 6-0-P-D-glucopyranosyl-p-D-glucopyranosides
(gentio-biosides ), 6-0-a-L -rhamnopyra nosyl-p-D-g lucopyra nos ides (rutinos ides), or
6-0-p-D-apiofuranosyl-p-D-glucopyranosides of mainly linalool, geraniol, nerol, a-terpineol
and hotrienol. These precursors are, however, hydrolyzed only to a limited extent by
endogenous glycosidases during the fermentation process, as they exhibit very low activity
in wine conditions.
The monoterpenols can be released from their sugar moieties by one of two
methods: either an acid or an enzymatic hydrolysis. The enzymatic hydrolysis mechanism
is fully understood, and the process functions in two successive steps: firstly, depending on
the precursor, the glycosidic linkage is cleaved by an a-L-arabinofuranosidase, an
a-L-rhamnosidase, a p-D-xylosidase, or a p-D-apiosidase. The second step involves the
liberation of the monoterpene alcohol by a p-glucosidase. This enzymatic hydrolysis does
not influence the intrinsic aromatic characteristics of the wine, as opposed to acid
hydrolysis.
As the endogenous grape glycosides of Vitis vinifera and the yeast Saccharomyces
cerevisiae show very low activity towards these aromatic precursors during the handling of
the juice and winemaking processes, the focus has increasingly fallen on introducing
exogenous p-glucosidases to wines and juices. Genes encoding p-glucosidases and
a-L-arabinofuranosidases have been cloned from various organisms, including bacteria,
fungi and yeasts. However, the activities and properties of these enzymes are not always
suitable for exploitation under winemaking conditions, where a low pH, low temperatures,
and high ethanol and glucose concentrations prevail. A genetically engineered wine yeast
strain of S. cerevisiae that expresses glycosidases that are active in these conditions would
be useful in improving the flavour and aroma of wines, thereby adding to the complexity
and value of the wine.
Two p-glucosidase genes, BGL 1 and BGL2 from Saccharomycopsis fibufigera, were
subcloned into two Escherichia coli-yeast shuttle vectors. A dominant selectable marker
gene (SMR1) was also inserted onto these plasmids. These plasmids were designated pBGL 1 (containing the BGL 1 gene) and pBGL2 (containing the BGL2 gene) respectively.
Introduction of the two plasmids into two strains of S. cerevisiae then followed. A laboratory
strain, L1278, was transformed to confirm the effective secretion of the expressed protein.
An industrial yeast strain, VIN13, was subsequently transformed by making use of the
selectable marker (resistance against sulfometuron). Enzyme assays with the synthetic
substrate p-nitrophenol-j3-D-glucopyranoside (pNPG) were performed to determine the
activity of the j3-glucosidases over a period of days, as well as at certain temperatures and
pH values. The stability of the enzymes was also investigated.
These recombinant yeasts were able to degrade the pNPG efficiently. They showed
promising results concerning pH optima, with a substantial amount of activity found at the
pH levels as found in the wine environment. There was also a slight increase in specific
activity at lower temperatures. The recombinant yeast strains were also tested in smallscale
fermentations. Three wines were made, of which two were from white cultivars
(Chenin blanc and GewOrtztraminer) and one from red (Pinotage). Results obtained from
micro-extraction from the finished wines showed that the terpenol content did increase,
although this was not the only wine component influenced. Other flavour compounds also
showed increases, especially the esters. This also played a role in the flavour increase in
the wine.
Future work would include optimizing the available results. This would entail the
addition of another glycosidic enzyme, such as a-L-arabinofuranosidase, to the genome of
the wine yeast to aid the further breakdown of glycosidic bonds. The cloning or engineering
of a j3-glucosidase enzyme that is more active at low temperatures would also yield better
results and release even more of the aroma of the wine. / AFRIKAANSE OPSOMMING: Monoterpeenalkohole (monoterpenole) speel 'n belangrike rol in die geur en aroma van
druiwe en wyn. Dit is veral van toepassing op wyne van Muskaat-varieteite, maar hierdie
geurkomponente is ook teenwoordig in ander nie-Muskaat druifsoorte, waar dit bydra tot
die varieteitsqeur en aroma. Hierdie monoterpenole kom voor in druiwe as vry, vlugtige en
aromatiese molekules, of as geurlose, nie-vlugtige glikosidies-gebonde komplekse. Hierdie
komplekse is meestal in die vorm van 6-0-a-L-arabinofuranosiel-~-D-glukopiranosiede, 6-
O-~-D-xilopiranosiel-~-D-glukopiranosiede (primverosiede), 6-0-~-D-glukopiranosiel-~-Dglukopiranosiede
(gentiobiosiede), 6-0-a-L-ramno-pyranosiel-~-D-glukopiranosiede
(rutinosiede), of 6-0-~-D-apiofuranosiel-~-D-glukopirano-siede van hoofsaaklik linalool,
geraniol, nerol, a-terpineol en hotrienol. Hierdie geurvoorlopers word egter slegs tot In
beperkte mate tydens die proses van fermentasie deur die endogene glikosidase ensieme
gehidroliseer, aangesien hulle baie min aktiwiteit toon onder wynbereidingstoestande.
Die monoterpenole kan op een van twee wyses van hul suikermolekules vrygestel
word: 'n suurhidrolise, of ensiematiese hidrolise. Die ensiematiese hidroliseproses word
baie goed begryp en behels twee opeenvolgende stappe: eerstens, afhangende van die
aard van die voorloper, word die glikosidiese verbinding deur In a-L-arabinofuranosidase, In
a-L-ramnosidase, In ~-D-xilosidase, of 'n ~-D-apiosidase gebreek. In die tweede stap word
die monoterpeenalkohol deur In ~-glukosidase vrygestel. Hierdie ensiematiese
afbraakproses verander nie die intrinsieke aromatiese kenmerke van die wyn, soos wat met
suurhidrolise die geval is nie.
Omdat die endogene glikosidases van Vitis vinifera en die van die gis
Saccharomyces cerevisiae baie lae aktiwiteit ten opsigte van die aromatiese voorlopers
gedurende die hantering van die druiwesap en wynmaakprosesse toon, val die fokus al hoe
meer op die inkorporering van eksogene ~-glukosidases in wyn en sappe. Gene wat vir ~-
glukosidases en a-L-arabinofuranosidases kodeer, is al vanuit verskeie organismes
gekloneer, insluitende bakteriee, fungi en giste. Die aktiwiteite en kenmerke van hierdie
ensieme is egter nie altyd wenslik vir hul gebruik in wyn nie, aangesien dit In omgewing is
met 'n lae pH, lae temperatuur, en hoe etanolvlakke en glukose-konsentrasies. In geneties
veranderde wyngis van S. cerevisiae wat in staat is om glikosidases uit te druk wat onder
hierdie kondisies aktief is, sal baie handig te pas kom in die verbetering van die geur en
aroma van wyne, om daardeur die kompleksiteit en die waarde van die wyn te verhoog.
Twee ~-glukosidasegene, BGL 1 en BGL2 vanaf die gis Saccharomycopsis
fibuligera , is in twee afsonderlike Esccherichia coli-gis-pendelplasmiede gesubkloneer. In
Dominante selekteerbare merkergeen (SMR1) is ook in hierdie plasmiede gekloneer.
Hierdie plasmiede word onderskeidelik pBGL 1 (met die BGL 1-geen) en pBGL2 (bevattende die BGL2-geen) genoem. Hierdie twee plasmiede is hierna apart na twee rasse van
S. cerevisiae getransformeer. Eerstens is 'n laboratoriumras, L1278, getransformeer om te
bevestig dat effektiewe sekresie en uitdrukking van die proteTen plaasvind. Hierna is 'n
industriele gisras, VIN13, getransformeer deur gebruik te maak van die selektiewe merker
(bestandheid teen sulfometuron). Ensiem-bepalings met behulp van die sintetiese
substraat p-nitrofeniel-p-O-glukopiranosied (pNPG) is gedoen om die aktiwiteit van die
p-glukosidqses oor 'n aantal dae te bepaal, asook om die aktiwiteit by sekere temperature
en pH-vlakke te meet. Die stabiliteit van die ensieme is ook bepaal.
Hierdie rekombinante giste was in staat om pNPG effektief af te breek. Hulle het
belowende resultate betreffende die pH-optima getoon, met 'n aansienlike hoeveelheid
aktiwiteit by die pH-vlakke soos dit in die wynomgewing voorkom. Daar was ook 'n effense
verhoging in die ensieme se aktiwiteite by laer temperature. Die rekombinante gisrasse is
ook in kleinskaalse wynfermentasies gebruik. Drie verskillende wyne is gemaak, waarvan
twee wit kultivars was (Chenin blanc en GewOrtztraminer) en een 'n rooi kultivar (Pinotage).
Resultate wat deur die mikro-ekstraksie van die voltooide wyne verkry is, het getoon dat die
terpenolinhoud wei verhoog het, alhoewel dit nie die enigste wynkomponente was wat
beinvloed is nie. Ander geurkomponente het ook 'n verhoging in konsentrasie getoon, veral
die esters. Hierdie verbindings het ook 'n rol in die verhoging van geur in die wyne gespeel.
Toekomstige werk sal die beskikbare resultate verder optimaliseer. Dit sal insluit die
byvoeging van nog 'n glikosidiese ensiem, soos a.-L-arabinofuranosidase, tot die genoom
van die wyngis, om verdere afbraak van glikosidiese verbindings teweeg te bring. Die
klonering of verandering van 'n p-glukosidase-ensiem met verhoogde aktiwiteit by laer
temperature sal ook beter resultate toon en meer geur in die wyn kan vrystel.
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The influence of base wine composition and wood maturation on the quality of South African brandySnyman, Caroline Lucie Charlotte 03 1900 (has links)
Dissertation (PhD)--University of Stellenbosch, 2004. / ENGLISH ABSTRACT: Brandy production is a multi-step process that involves grape harvesting, base wine
fermentation, distillation, wood maturation and blending. Within each of these production
process steps there are a number of factors that can influence the composition and
resultant quality of the base wine, unaged and wood matured distillates. These factors
include geographic and climatic features of the origin of grapes used, viticultural practices,
grape maturity, grape variety, vintage variation, vinification techniques, storage of the base
wine prior to distillation, distillation technique, age and origin of oak wood used for
maturation and barrel toasting levels.
The composition of flavour is extremely complex in wine and distilled beverages such
as brandy. A multitude of compounds can take part in the formation of flavour, and it is
rare that a particular compound, that is solely responsible for nuances of a specific flavour,
is identified. Thus, taking brandy production factors and the nature of aroma and flavour
into account, it is clear that thorough understanding of the complexities affecting the
perception of quality in brandy is difficult.
In commercial brandy production, standard operating procedures do not allow for the
separate distillation of brandy base wines from different producers and mixing of base
wines from different regions and producers thus occurs. This makes it difficult to determine
whether the quality determination of the base wine is in fact an indication of the quality of
the resultant distillate after the required period of wood maturation. Therefore, the aim of
this study is to determine whether there is any merit in storing and distilling brandy base
wines from different producers and regions separately. This was done by firstly
determining the demographic and production factors that influence brandy base wine
composition. Secondly, the influence of brandy base wine composition on the quality of the
respective unaged potstill distillates as well as the ultimate style and quality of the threeyear
old wood matured potstill distillates was determined.
For this purpose, four potstills with a capacity of 2000 L each were isolated and used
for commercial scale distillations of 33 and 25 brandy base wines in 1999 and 2000,
respectively, at the DisteIl distillery in Worcester. The experimental outlay used in the
study closely emulated Distell's standard operating procedures for commercial brandy
production.
Chenin blanc and Colombar are the two most popular grape varietals used in the
making of brandy base wine in South Africa. Due to the complexity of the brandy
production process, the first part of the study only focussed on South African young
Chenin blanc wines, with a predominantly fermentation derived aroma. The concentration
of iso-amyl acetate, hexyl acetate, ethyl caprylate, ethyl caprate, 2-phenethyl acetate and
octanoic acid was significantly higher in wines awarded gold and silver medals and
decreased significantly with subsequent decreases in quality categories. Ethyl lactate
exhibited the opposite pattern. A quality predictor model based on the behaviour of 21 volatile compounds quantified in these wines had a resonable prediction accuracy when
having to predict the quality of wines made in the same vintages as it had been trained on.
It was significantly poorer when tested on a completely different vintage of wines to the
ones it had been trained on. The number of vintages, number of wines per vintage and the
number of compounds quantified for the model influence its prediction accuracy.
Twenty-seven volatile compounds were quantified in 33 and 25 brandy base wines,
their unaged and three year old distillates from 1999 and 2000, respectively. ANOVA and
CART analysis showed that vintage, region, harvest time, choice of cultivar and yeast
strain can have a significant influence on the volatile compound composition of brandy
base wines, their unaged and three year old distillates. These factors as well as the
volatile compound composition were also found to influence the sensory quality of these
products. Base wines, unaged and three year old distillates originating from the De Dooms
region, which predominantly cultivates table grapes, were of significantly lower quality than
those from the remaining regions. Products made from grapes harvested early in the
season were of significantly higher quality. The volatile aroma compound composition was
found to differ significantly between the 1999 and 2000 base wines and distillates,
irrespective of the exclusion of those samples that had undergone partial or complete
malolactic fermentation. Consequently, quality indicating compounds may vary from
vintage to vintage. The relationship between the quality of brandy base wines and the
concentration of n-butanol, iso-amyl acetate, ethyl lactate, ethyl caprylate, octanoic- and
decanoic acid was the same as that reported in young Chen in blanc wines in this study. In
unaged distillates, increased levels of ethyl lactate also exert a negative influence on
distillate quality. Iso-amyl acetate, hexyl acetate, ethyl caproate, ethyl caprylate, n-butanol,
octanoic acid, ethyl caprate and decanoic acid showed some positive correlation, whilst
iso-butanol, ethyl lactate, acetic acid, acetaldehyde and ethyl acetate showed a significant
negative correlation to three-year old distillate quality.
Sensory descriptive analysis on selected good, average and poor quality distillates
using the South African brandy aroma wheel showed that there are small differences in
profile between the good and average distillates, there were however significant
differences between the good and poor quality distillate profiles throughout maturation.
After three years of wood maturation, the aroma profile of poor quality distillates can be
characterised by prominent herbaceous and woody aromas, which are more intense than
the fruity aromas. Good quality distillates contained characteristically intense fruity aromas.
Volatile compound concentration differences were noted during the course of and after
three years of wood maturation and in barrels of varying ages. Distillates matured in new
block barrels exhibited significant differences in volatile and wood compound composition
after three years when compared to remaining barrels used. The style classification of the
three-year old potstill distillate was influenced by demographic and production factors and
volatile compound composition, but not by the sensory quality of the distillates.
In summary, vintage, region, cultivar, harvest time and choice of yeast strain have a
significant influence on the volatile composition of brandy base wines, their unaged and three year old potstill distillates, which in turn affects the sensory quality of these products.
These effects cannot be viewed in isolation as they jointly exert an influence on the
composition and quality of these products. From a commercial perspective, this study has
provided a valuable indication as to which production and demographic factors can
influence the quality and style of potstill brandy. Thus, future brandy base wine intake
should, as far as possible, take place in such a manner to allow base wines originating
from the same cultivar or region or harvest time or combination thereof (and to a lesser
extent yeast strain) to be received simultaneously at the distillery for distillation. / AFRIKAANSE OPSOMMING: Brandewyn produksie is 'n veelvoudige proses wat die volgende insluit: pars van druiwe,
basiswyn fermentasie, verstoking, houtveroudering en versnyding. Binne hierdie stappe is
verskeie faktore wat 'n invloed op die samestelling en resultate van die basiswyn,
onverouderde en verouderde distillaat kan hê. Hierdie faktore sluit die volgende in:
geografiese ligging, klimaat toestande van die streek van herkoms, wingerdboupraktyke,
graad van rypheid, druifvarieteit, wynoes variasie, wynbou tegnieke, opberging van
basiswyn voor distillasie, distillasie tegnieke, ouderdom en oorsprong van akkerhout vir die
veroudering, asook tot watter mate die vat gerooster is.
Die samestelling van geur in wyn en gedistilleerde produkte soos brandewyn is uiters
kompleks. 'n Menigte samestellings kan deel vorm van die inhoud van die geur, en dit is
raar dat 'n bepaalde verbinding alleenlik verantwoordelik is vir 'n kenmerkende geur.
Weens die verskeidenheid van produksie faktore, aroma en smaak is volledige kennis van
brandewyn ingewikkeld en kompliseerd om te verstaan.
In kommersiële brandewynproduksie, maak standaard werksprosedures nie
voorsiening vir aparte distillasie van basiswyn van verskillende produsente nie, en die
vermenging van basiswyn van verskillende streke en produsente kom voor. Dit maak dit
moeilik om te bepaal of die kwaliteit van die basiswyn of die distillaat na die neergelegde
periode van houtveroudering, in werklikheid 'n beslissende indikasie op die kwaliteit van
die verouderde produk is. Daarom is een van die doele van hierdie studie om te bepaal of
daar meriete in is om brandewyn basiswyn van die verskillende produsente en streke
apart te berg en te verstook. Dit is gedoen deur eerstens, die effek van demografiese en
produksie faktore op die samestelling van brandewyn basiswyn te bepaal. Daarna, om die
invloed van brandewyn basiswynsamestelling op die kwaliteit van onderskeidelik die
onverouderde distillate sowel as die uiteindelike styl en kwaliteit van die 3 jaar oue
houtverouderde potketel distillate, te bepaal.
Vir hierdie doel, is vier potketels met 'n kapasiteit van 2000 liters elk geïsoleer en vir
kommersiële skaal distillasies van 33 en 25 brandewyn basiswyne in 1999 en 2000,
ondeskeidelik, by DisteIl Distillerdery, Worcester verstook. Die eksperimentele uitleg wat
in hierdie studie gebruik is, ewenaar DisteIl se standaard verstokingsprosedures vir
kommersiële brandewynproduksie.
Chenin blanc en Colombar is die twee mees populêre druifvarieteite vir die maak van
brandewyn basiswyn in Suid-Afrika. As gevolg van die kompleksiteit van die brandewyn
produksieproses, is die eerste gedeelte van die studie gefokus op die Suid-Afrikaanse jong
Chenin blanc wyne, met 'n oorheersende fermentasie geur. Die konsentrasie van iso-amyl
asetaat, heksiel asetaat, etiel kaprilaat, etiel kapraat, 2-phenetiel asetaat en oktanoë suur
was aansienlik hoër in wyne wat met goud en silwer medaljes bekroon is en neem
aansienlik af met afname in kwaliteit kategorieë. Etiel laktaat vertoon die teenoorgestelde
patroon. 'n Kwaliteit voorspellersmodel, gebaseer op die gedrag van 21 vlugtige komponente was opgestel. Die model het redelike akkuraatheid getoon op wyne van
dieselfde oesjaar as waarop oorspronklik opgelei. Die model se voorspellingsakkuraatheid
was aansienlik swakker toe dit vergelyk getoets is met wyne van 'n nuwe oesjaar. Die
hoeveelheid oesjare, hoeveelheid wyne per oesjaar en die hoeveelheid verbindings
gebruik in hierdie model sal die voorspellingsakkuraatheid beïnvloed.
Sewe-en-twintig vlugtige komponente was gekwantifiseer in 33 en 25 brandewyn
basiswyne, die onverouderde en 3 jaar oue distillate vanaf 1999 en 2000, onderskeidelik.
Variasie ontledings (ANOVA) en klassifikasie en regressie ontledings (CART) ontledings
wys dat oesjaar, streek, parstyd, keuse van kultivar en gisrasse In aansienlike invloed op
die vlugtige samestelling van brandewyn basiswyne asook hul onverouderde en 3 jaar
distillate het. Hierdie faktore, sowel as die vlugtige verbinding samestellings, beinvloed
ook bevind die sensoriese kwaliteit van hierdie produkte. Basiswyne, onverouderde en 3
jaar oue distillate wat vanuit die De Doorns streek, wat hoofsaaklik tafeldruif kultivars is, is
van In swakker kwaliteit as die ander streke. Produkte wat gemaak is van druiwe wat
vroeg in die seisoen gepars is, was van beter kwaliteit. Die vlugtige
geurkomponentsamestellings het tussen die basiswyne en distillate van die 1999 en 2000
oesjare verskil, ongeag of party van die monsters gedeeltelike of volledige
appelmelksuurgisting ondergaan het. Gevolglik, die konsentrasie van kwaliteitaanwysende
komponente mag van seisoen tot seisoen verskil. Die verhouding tussen die kwaliteit van
die brandewyn basiswyne en die konsentrasie van n-butanol, iso-amiel asetaat, etiel
laktaat, etiel kaprilaat, oktanoë- en dekanoë suur was dieselfde soos gerapporteer oor die
jong Chenin blanc wyne. In onverouderde distillate, het verhoogde vlakke van etiel
laktaat In negatiewe invloed op distillaat kwaliteit veroorsaak. Iso-amiel asetaat, heksiel
asetaat, etiel kaproaat, etiel kaprilaat, n-butanol, oktanoë suur, etiel kapraat en dekanoë
suur In positiewe korrelasie, terwyl iso-butanol, etiel laktaat, asynsuur, asetaldehied en
etiel asetaat betekenisvolle negatiewe korrelasie met 3jaar oue distillaat kwaliteit bewys.
Beskrywende sensoriewe analises op geselekteerde, middelmatige en swak kwaliteit
distillate (gedoen deur gebruik making van die Suid-Afrikaanse Brandewyn Aromawiel)
wys dat daar klein verskille tussen die profiele van goeie en middelmatige distillate is.
Daar is egter aansienlike verskille tussen goeie en swak kwaliteit distillataat profiele
regdeur die drie jaar verouderingsperiode. Na 3 jaar van houtveroudering kan die geur
profiel van swak kwaliteit distillate uitgeken word aan kruid- en houtagtige geure, wat meer
intens as die vrugagtige geure is. Goeie kwaliteit distillate het intense vrugagtige-aroma
eienskappe.
Vlugtige verbinding konsentrasie verskille is waargeneem gedurende en na die 3jaar
houtverouderingsperiode in vate wat van ouderdomme verskil. Distillate wat in nuwe
blokkies vate verouder is, vertoon aansienlike verskille in vlugtige en houtkomponent
samestellings na 3 jaar wanneer dit met die, wat in die oorblywende ouer vate verouder is,
vergelyk word. Die styl klassifikasie van die 3 jaar oue potketeldistillaat was deur
demografiese en produksie faktore sowel as vlugtige verbinding samestellings beïnvloed,
maar nie met die sensoriese kwaliteit van die distillate nie. In opsomming, oesjaar, streek, kultivar, parstyd en keuse van gisrasse het 'n
aansienlike invloed op die vlugtige komponent samestelling van die brandewyn basiswyne,
onverouderde en 3 jaar oue potketel distillate, wat weer op hul beurt die sensoriese
kwaliteit van die onderskeidelike produkte beïnvloed. Die effek van hierdie faktore kan nie
in isolasie gemeet word nie, aangesien dit gesamentlik die kwaliteit van die produkte
beïnvloed. Van 'n kommersiële perspektief het hierdie studie 'n waardevolle indikasie
gelewer van hoe produksie en demografiese faktore die kwaliteit en styl van
potketelbrandewyn kan beïnvloed. Daarom word voorgestel dat toekomstige brandewyn
basiswyn innames, sover as moontlik, voorsiening moet maak om wyne van dieselfde
kultivar, uit dieselfde streek, parsseisoen inaggeneem, of kombinasie daarvan, met 'n
mindermate die gisrasse in aanmerking geneem, gelyktydig vir verstoking by die
distilleerderye ontvang word sodat hierdie wyne apart van wyne met ander bogenoemde
variasies verstook en verouder kan word.
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