Thesis (M.B.A.)--University of Hong Kong, 1996. / Includes bibliographical references.

Thesis (PhD)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: Aged distilled spirits such as whiskey are complex mixtures of flavour compounds in an ethanol-water matrix. The flavour compounds involved can have widely different volatility and relative amounts. Many of the organoleptic properties that make whiskey suitable for commercial sale have their origin in reactions occurring during the ageing process in oak wood barrels. To investigate the complex changes that take place during spirit ageing a preparative fractional vacuum distillation process was developed. Both high and low volatility compounds could be individually isolated as fractions and free from both the ethanol matrix and the fermentation fusel alcohols. This allowed a range of sensory and analytical procedures to be conducted on these fractions, in particular to investigate changes occurring during ageing. Gas chromatographic (GC) analysis of the low volatility fraction is complicated by the fact that both the compounds and their ethanol matrix have very similar chromatographic behaviour when separated simultaneously on standard chromatographic phases. Compound and matrix co-elution becomes a major problem and conditions for mass spectrometric (MS) investigation are disadvantageous. A two-dimensional GC configuration using dissimilar chromatographic phases was configured to overcome these limitations. Using this approach 27 compounds were separated and identified. Headspace injection was used to increase detection sensitivity. Changes with ageing for seven compounds present at very low levels were quantified. In addition changes in the most abundant compounds were quantified by standard split injection, and changes in trace level sulfur compounds by headspace injection with sulfur chemiluminescent detection (SCD). Increases of the concentrations of pleasant fruity ethyl esters and acetates were established. Volatile sulfides with generally objectionable aroma showed concomitant major decreases. Appropriate techniques could also be applied to the low volatility compounds recovered from the whiskey water fraction. High temperature GC-MS analysis of an extract of the water fraction allowed the identification of 30 compounds. Three phenolic esters were identified in whiskey for the first time. These compounds were synthesised and shown to be contributory to desirable ageing flavour. Increases in concentrations of 16 oak derived compounds during alO year ageing period were established. Several compounds increased significantly over this time period. Ratios of aromatic phenolic aldehydes, and changes in these ratios during ageing, were unique to the type of barrel used in these experiments. This suggests that the final sensory properties of aged whiskey may be more dependent on wood parameters than previously thought. Preparative reverse phase High Pressure Liquid Chromatography (HPLC) with an ethanol water gradient was used to further fractionate an extract of the low volatility compounds. Subsequent analysis and sensory testing allowed a group separation of compounds with each group contributing characteristic attributes to the total flavour. One group contained the three new phenolic esters together with a number of other unidentified compounds. This group was found to be important for desirable ageing flavour that seems to develop slowly with time. Further studies in this area to understand the individual and synergistic contributions of the many facets of ageing chemistry will have important commercial implications. / AFRIKAANSE OPSOMMING: Verouderde spiritus soos Whiskey is 'n komplekse mengsel van geurstowwe in 'n etanolwater oplossing. Die vlugtigheid van die geurstowwe asook die konsentrasies waarin hul aanwesig is, varieer aansienlik. Verskeie van die sintuiglike eienskappe wat kommersiële waarde aan whiskey verleen, het huloorsprong in reaksies wat tydens die verouderingsproses in eikehoutvate plaasvind. Ten einde die ingewikkelde veranderinge wat tydens die veroudering van spiritus plaasvind, te ondersoek, is 'n preparatiewe fraksionele vakuumdistillasieproses ontwikkel. Hoogs vlugtige en minder vlugtige verbindings kon geskei word in afsonderlike fraksies wat vry was van etanol en fuselalkohole. Dit het die sintuiglike en fisies-chemiese analises van die fraksies moontlik gemaak, veralom die veranderings wat tydens veroudering plaasvind, te ondersoek. Gaschromatografiese (GC) analise van die fraksie met 'n lae vlugtigheid word gekompliseer deur die feit dat hierdie komponente en die etanol waarin dit opgelos is soortgelyke chromatografiese eienskappe toon wanneer hul gelyktydig op standaard gaschromatografie fases geskei word. Die gelyktydige eluering van dié komponente en etanol waarin hul opgelos is, skep 'n probleem wat nadelig vir massaspektrometriese (MS) analise is. Die beperkings is oorkom deur die gebruik van tweedimensionele GC en stasionêre fases met uiteenlopende eienskappe. Op dié wyse is 27 verbindings geskei en geïdentifiseer. Die veranderinge in konsentrasies tydens veroudering is vir sewe verbindings gekwantifiseer. Veranderinge in die konsentrasies van die verbindings teenwoordig in die hoogste konsentrasies is gekwantifiseer deur split-inspuitings, terwyl veranderinge in die spoorkonsentrasies van vlugtige swawelverbindings mbv dampfase-inspuitings en met swawel chemolumisensie deteksie (SCD) bepaal is. Toenames in die konsentrasies van die aangename vrugtige esters en asetate is bepaal. Vlugtige sulfiede met meesalonaanvaarbare aromas toon gelyktydige groot afnames. Geskikte tegnieke is ook gebruik vir die herwinning van minder vlugtige verbindings met die waterfase van whiskey. Hoë temperatuur GC-MS analises van 'n ekstrak van die waterfase het die identifikasie van 30 komponente moontlik gemaak. Drie fenoliese esters is vir die eerste keer in whiskey gevind. Hierdie verbindings is gesintetiseer en hul bydrae tot die gewenste verouderingsgeur is sintuiglik bevestig. Toenames in die konsentrasies van 16 eikehoutverwante verbindings gedurende 'n verouderingsperiode van 10 jaar is bepaal. 'n Betekenisvolle toename het voorgekom in die konsentrasies van verskeie van hierdie whiskey verbindings. Die verhoudings van aromatiese fenoliese aldehiede en die verandering in die verhoudings tydens veroudering was kenmerkend van die tipe eikehoutvat wat gebruik is. Dié bevinding dui daarop dat die fenole sintuiglike eienskappe van verouderde whiskey meer afhanklik mag wees van eikehout parameters as wat voorheen algemeen aanvaarbaar is. Preparatiewe omgekeerde fase hoëdrukvloeistofchromatografie met etanol/water as 'n gradient elueermiddel is gebruik om 'n ekstrak van die minder vlugtige verbindings verder te fraksioneer. Verdere GC-, MS- en sintuiglike analise het die skeiding van groepe van verbindings waarvan elk kenmerkende bydraes tot die totale geur lewer, moontlik gemaak. Een groep het drie nuut geïdentifiseerde fenoliese esters, tesame met 'n aantal ongeïdentifiseerde verbindings, bevat. Daar is vasgestel dat hierdie groep 'n belangrike bydrae maak tot die gewenste geur wat klaarblyklik stadig tydens veroudering ontwikkel. Verdere ondersoeke in hierdie verband om die individuele en sinergistiese bydraes van verskeie fasette van die chemie van veroudering te verstaan, kan belangrike kommersiële implikasies hê.

No description available.

I uppsatsen behandlas tre reklambilder för whiskey utifrån teorier om klassisk retorik, visuell retorik och semiotik. Hypotesen för whiskeyn och dess reklam är att avsändaren måste övertyga betraktaren om att åsidosätta en viss typ av negativa associationer som finns i samband med alkohol för att den ska få en önskad effekt.  I uppsatsen undersöks begreppen ethos, logos och pathos i samband med bildernas retoriska utgångspunkter. Här hävdas att det finns mönster eller olika strategier och tendenser i bildernas uttryck. Dessa mönster är intressanta eftersom de positionerar whiskeyn som produkt och övertygar betraktaren om hur whiskey ska uppfattas.  Retorikens utveckling beskrivs tillsammans med semiotiken och en analys presenteras i en avslutande del inspirerad av Bo Renbergs modell för retorikanalys.  Generellt framhåller författaren att reklambilderna byggs upp på ett liknande sätt eftersom de tillhör samma produktkategori. Denna kategori distanserar sig i sitt budskap från andra typer av alkohol.

<p>I uppsatsen behandlas tre reklambilder för whiskey utifrån teorier om klassisk retorik, visuell retorik och semiotik. Hypotesen för whiskeyn och dess reklam är att avsändaren måste övertyga betraktaren om att åsidosätta en viss typ av negativa associationer som finns i samband med alkohol för att den ska få en önskad effekt. </p><p>I uppsatsen undersöks begreppen ethos, logos och pathos i samband med bildernas retoriska utgångspunkter. Här hävdas att det finns mönster eller olika strategier och tendenser i bildernas uttryck. Dessa mönster är intressanta eftersom de positionerar whiskeyn som produkt och övertygar betraktaren om hur whiskey ska uppfattas. </p><p>Retorikens utveckling beskrivs tillsammans med semiotiken och en analys presenteras i en avslutande del inspirerad av Bo Renbergs modell för retorikanalys. </p><p>Generellt framhåller författaren att reklambilderna byggs upp på ett liknande sätt eftersom de tillhör samma produktkategori. Denna kategori distanserar sig i sitt budskap från andra typer av alkohol.</p>

Oak casks are used for the maturation of a wide variety of alcoholic beverages including Scotch whisky. The process of maturation has a profound but variable effect on the colour and flavour of the whisky, with cask wood playing an important role, particularly through the release of extractives to the distillate. This thesis examines variation in European oak wood (Quercus petraea Matt. Liebl. and Q. robur L.) of ellagitannins, oak lactones and other extractives, and physical wood properties. Investigations particularly sought to establish whether the properties and their effects on flavour can be predicted from either the species, the various forest origins, or identifiable wood or tree characters. The treatment of wood after felling, through seasoning and particularly the toasting or charring of casks, has a major effect on the levels of many extractives. Heating reduces the concentrations of ellagitannins and increases levels of lignin-derived extractives. However, the effects are not such as to render variation in untreated wood inconsequential. Within trees, the concentration of soluble ellagitannins declines and the composition changes with heartwood age. When heartwood of a similar age is compared concentrations vary by up to ten times between different trees, making up to 14% of the heartwood dry weight. Concentrations of oak lactones appear to increase with heartwood age and are also very variable between trees. Wood samples were taken from two different forests, corresponding to opposing types of French oak used for cooperage. Over 70% of the total variation of soluble tannins in the wood occurred between the forests. A difference between the two forests in the rate of tree growth and the heartwood age of samples could not explain all of the difference in the amounts of soluble tannins. After heating the wood, the concentrations of other extractives and the flavour and colour imparted to solutions, also varied significantly between the two forests and between trees within each site. Studies on clonal, progeny and provenance material concluded that the concentration of ellagitannins, oak lactones and many physical properties of heartwood are under strong genetic control. However, a large proportion of this variation is attributable to variation between the two species Q. robur and Q. petraea. Q. robur is characterised by high concentrations of tannins and, after heating, of lignin-derived products, but low or negligible levels of oak lactones. Q. petraea has opposing extractive properties and after heating, imparts a more pleasant and complex flavour. Although there is large variation between trees within each species, this difference between the species is proposed as the main factor explaining the different flavour and extractive properties found in European oak wood from different origins.

Thesis (M.Eng.)--University of Louisville, 2008. / Title and description from thesis home page (viewed May 15, 2008). Department of Chemical Engineering. Vita. "December 2008." Includes bibliographical references (p. 42).

Thesis (doctoral)--Universität Münster, 2006. / Vita. Includes bibliographical references (p. 215-225).

Thesis (MSc)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: Scotch whiskey is of two main types, namely Scotch malt whiskey, made from malted barley alone, or Scotch grain whiskey, made from cereals, such as wheat or maize, together with malted barley. In both processes, the enzymes from the barley are responsible for starch conversion and should always be derived entirely from the malted barley. No exogenous enzymes are allowed to be added to any mashing. The enzymes involved in the conversion process to fermentable sugars, are the aand p-amylases, limit dextrinase and p-glucosidase. Maize, on the other hand, contains no enzyme activity, therefore enzymes need to be added when producing whiskey from maize alone. In other whiskey-producing countries where maize is freely available and cheaper than barley, the use of exogenous enzymes are allowed in the mashing process and is crucial for the formation of fermentable sugars from complex carbohydrates. The cost of the enzymes, however, can push the production cost of whiskey to higher levels. Saccharomyces cerevisiae does not have any amylolytic activity, but is an excellent fermenter and produces favourable organoleptic notes, which makes it very suitable for producing potable spirit. Efforts have been made to genetically improve industrial strains, relying on classical genetic techniques followed by the selection of broad traits, such as ethanol tolerance, absence of off-flavours and carbohydrate/starch utilisation. No strain has thus far been selected for total starch degradation during the fermentation of whiskey mash. Over the last decade, considerable progress has been made in the development of genetically improved strains for the distilling, wine, brewing and baking industries. The expression of heterologous genes introduced a new dimension in approaches to the genetic improvement of industrial strains. It would therefore be cost-effective to use a yeast strain that can produce active and sufficient enzymes to ferment raw starch efficiently to alcohol without lowering the quality of the end product. No such strain has been developed to date, but the continuous improvement of starch-utilising strains has made this goal more achievable. Two a-amylase genes, namely LKA 1 and LKA2, were previously isolated from Lipomyces kanonenkoae. In this study, we selected 4 strains on the basis of criteria that are important for whiskey-specific strains. The selected strains were transformed with LKA 1, as well as with a combination of LKA 1 and LKA2 genes. The wine yeast VIN13 was included in the transformation of LKA1 and LKA2 because of its rapid fermentation rate. The genes were integrated into the genomes of the yeast strains and were stable after many generations. Assays showed that a significant increase in enzyme activity was induced in the whiskey strains, compared to the untransformed strains. The strains also showed good fermentation ability in whiskey fermentations, although optimum alcohol production was still not achieved. / AFRIKAANSE OPSOMMING: Skotse whiskey bestaan uit 2 tipes, nl. mout whiskey, gemaak slegs van mout d.w.s. gars wat die mout proses ondergaan het, en graan whiskey wat gemaak word van gewasse soos mielies of koring, waarby mout gevoeg word. Die ensieme afkomstig van die mout is verantwoordelik vir die omsetting van stysel na fermenteerbare suikers en geen eksogene ensieme mag by die gars- of graanmengsel gevoeg word nie. Die ensieme wat betrokke is by die omsetting van stysel, is die a- en ~- arnitases, limiet dekstrinase en ~-glukosidase. Mielies bevat geen ensiemaktiwiteit nie, dus moet ensieme by die proses gevoeg word indien slegs mielies vir die vervaardiging van whiskey gebruik word. In whiskey produserende lande waar mielies vryelik beskikbaar is en goedkoper is as gars, word eksogene ensieme by die graanmengsel gevoeg vir die vrystelling van fermenteerbare suikers vanaf komplekse koolhidrate. Die hoë koste van die ensieme kan egter die produksiekoste van whiskey verhoog. Saccharomyces cerevisiae besit geen amilolitiese aktiwiteit nie, maar is 'n uitstekende fermenteerder en produseer gewensde organoleptiese geure. Om hierdie redes is S. cerevisiae baie geskik vir die produksie van drinkbare etanol. Navorsingspogings om industriële rasse geneties m.b.v. klassieke genetiese metodes te verbeter, kom wydverspreid in die literatuur voor. Dit sluit in die seleksie van rasse met 'n verskeidenheid van eienskappe soos etanol toleransie, die afwesigheid van afgeur produksie en koolhidraat/stysel benutting. Geen ras is egter tot op hede geselekteer vir totale stysel afbraak gedurende fermentasie nie. Groot vordering is gedurende die laaste dekade gemaak in die ontwikkeling van genetiese verbeterde rasse vir die wyn- stokery- en brouers industrieë. Die uitdruk van heterogene gene in gisrasse gee 'n nuwe dimensie aan die genetiese verbetering van industriële rasse. Die gebruik van 'n gisras wat aktiewe en genoegsame ensieme produseer om rou stysel te fermenteer, sonder om die kwalitiet van die eindproduk nadelig te beïnvloed, kan die produksiekoste van whiskey aansienlik verminder. Geen gisras met hierdie eienskap is tot op hede ontwikkel nie, maar die voortdurende verbetering van rasse om stysel af te breek maak hierdie doel meer bereikbaar. Twee a-amilase gene, nl. LKA 1 en LKA2 is voorheen uit Lipomyces kononenkoae geïsoleer. In hierdie studie is 4 gisrasse geselekteer op grond van die kriteria wat nodig is vir whiskey giste. Die geselekteerde rasse is getransformeer met LKA 1 sowel as 'n kombinasie van LKA 1 en LKA2 gene. Die wyngis VIN13 is ingesluit by die transformasie met die LKA1 en LKA2 gene, omrede VIN13 bekend is as 'n vinnige fermenteerder. Die gene is geïntegreer in die genoom van die verskillende gisrasse en is stabiel na vele generasies. Die getransformeerde rasse het 'n betekenisvolle verhoging in ensiemaktiwiteit teenoor die nie-getransformeerde rasse getoon. AI die transformante het ook goeie fermentasie vermoë getoon in whiskey fermentasie proewe. Optimum alkoholproduksie is egter nie verkry nie.

published_or_final_version / Business Administration / Master / Master of Business Administration