Tesis sobre el tema "Odor quality"

The use of polymer pipes is now very common in home plumbing and other parts of the drinking water distribution system. Many taste and odor complaints in drinking water are known to originate from contact of water with materials. The ability of polymer pipes used in home plumbing to affect drinking water quality and aesthetics was investigated using the Utility Quick Test (UQT). Analysis of water quality and aesthetics were conducted in the absence of disinfectant and the presence of either chlorine or chloramines. A Flavor Profile Analysis (FPA) panel was trained according to Standard Methods 2170B to evaluate the organoleptic characteristics of the samples. Laboratory analyses were performed to determine levels of total organic carbon (TOC), disinfectant residual, pH and to attempt to identify specific volatile organics.

The first part of this study investigated HDPE, cPVC and epoxy lined copper pipes using the UQT method. Both HDPE and epoxy-lined copper had significant effects on water quality and aesthetics during the approximately 10 day exposure of the UQT. HDPE and epoxy-lined copper leached significant amounts of TOC and consumed more disinfectant than controls, but in different amounts. cPVC was the most inert of the materials tested and had the least impact on water quality and did not contribute any significant odor. None of the pipes tested appeared to contribute trihalomethanes to drinking water, but further analysis revealed that the compounds may actually be generated and subsequently sorbed into pipe walls. These data show the effects of newly installed polymeric pipe materials and their potential to impact water quality in differing capacities.

The second part of this study compared the results of the UQT on HDPE, epoxy lined copper, cPVC, PEX-a and PEX-b with the goal of comparing and contrasting how five different polymeric plumbing materials can impact drinking water quality. Results demonstrated the short-term ability of all pipe materials except cPVC to impact water quality and aesthetics. This data could potentially be useful in generating selection criteria for homeowners and plumbing professionals regarding the impact of newly installed plumbing materials.

Master of Science

The distribution system is the primary cause of taste and odor complaints in drinking water. This research examined the ability of small diameter pipes used in home plumbing to affect drinking water quality. The properties of the materials were investigated in the absence of disinfectant and the presence of either chlorine or chloramines. A panel was trained in flavor profile analysis (FPA) according to Standard Methods 2170B and used to assess the sensory properties of all samples. Chemical analyses were performed to determine disinfectants, total organic carbon (TOC), pH and specific organic contaminants. The first part of this study investigated PEX pipes manufactured by the silane (PEX-b) and peroxide (PEX-a) cross-linking technology, using the utility quick test (UQT) method. Silane PEX-b had a greater effect on water quality properties such as odor, TOC and residual disinfectant demand than peroxide-linked PEX-a. Chemical analysis revealed that PEX pipes can contribute fuel oxygenates such as ETBE (PEX-b) and possibly MTBE (PEX-a) to drinking water. PEX pipes did not contribute any significant trihalomethanes to drinking water. This study showed that the type of PEX used in homes will determine the extent to which drinking water quality is affected. The second part of this study used simulated plumbing rigs to investigate seven different materials under low flow and stagnant conditions; chlorinated polyvinyl chloride, cross-linked polyethylene, polyethylene, epoxy-lined copper, copper, stainless steel, galvanized iron and glass (control). Results showed that these plumbing materials have the potential to affect water quality characteristics such as TOC concentrations, residual disinfectant and odor when newly installed in homes. A high TOC concentration was consistent with the presence of a distinct odor or a high FPA intensity rating. Galvanized iron produced the worst odors that were consistently described as "motor oil". Polyethylene generated more intense plumbing associated odors than PEX or cPVC plastic material. cPVC and copper generated the least odors. Both copper pipe and epoxy-lined copper consumed residual chlorine and chloramines.
Master of Science

Thesis (PhD)--Stellenbosch University, 2005.
ENGLISH ABSTRACT: A number of relevant brewing industry issues associated with malt quality were examined. These included beer foam quality, premature flocculation of yeast during fermentation and antimicrobial factors in malt. The cause of poor foam at a brewery relative to other similar breweries was identified as being related to the boiling temperature during wort preparation and the associated conformational changes of the abundant foam protein lipid transfer protein 1 (LTPl). The temperature range of 96 to 102°C was revealed to be critical. At the higher temperature the denaturation of LTP 1 was more extensive and its effectiveness as a foam protein was reduced. In addition, it was shown that the prominent role of LTPI with respect to foam was as a lipid binding protein, forming a lipid sink and protecting foam from lipid damage. The occurrence of malt associated premature yeast flocculation (PYF) during fermentation was induced in malt by the addition of extra-cellular fungal enzymes to the malt husk or by micro-malting barley in the presence of fungi. In addition, treating malt husk with commercial xylanase or adding commercial arabinoxylan to the fermentation also impacted on yeast flocculation. It was proposed that a range of molecular weight arabinoxylans formed by the enzymatic breakdown of the major barley husk component (arabinoxylan) resulted in PYF. Antimicrobial activity against brewing yeast (Saccharomyces cerevisiae), other fungi and bacteria was found in barley, malt and malt derived wort trub. Wort trub is the non-specific precipitate of protein, polyphenols and lipids formed during wort boiling and which is, to some extend, carried over in the wort to the fermentation. Antimicrobial activity appeared to increase during malting. The growth of brewery collected yeast was inhibited in the presence of brewery production wort when compared to the same wort filtered to remove the trub. Brewery yeast was found to be more sensitive to inhibition than laboratory propagated yeast of the same strain. Different strains of S. cerevisiae were also found to differ in their sensitivity to inhibition. Investigation revealed that the activity originated from the inside of the barley grain and impacted on yeast sugar uptake. However, there was no direct correlation detected between levels of antimicrobial activity in malt and fermentation performance. At high concentrations the factors were microcidal causing cell lysis. Partial characterisation of an antimicrobial extract from malt revealed the presence of a factor between 5 and 14 kDa, containing a cationic peptide component. The optimum pH stability was ±5 when it was also most cationic. The factor easily and irreversibly lost activity at extreme pH and when exposed to certain reagents but was heat resistant in accordance with its survival in wort trub. Preliminary results showed the presence of LTP1 associated with other peptides in the active cationic fraction from the one malt tested. The occurrence of malt related PYF and malt antimicrobial factors are associated with microbial contamination of the grain. The fungi generating the PYF factors from the barley husk while the barley's defence mechanism generates antimicrobial factors to cope with the pathogenic effect of the fungi. In addition there is a potential link between the foam protein LTP 1 and malt antimicrobial activity as LTP 1 or LTP 1 in association with another component(s) is potentially antimicrobial.
AFRIKAANSE OPSOMMING: 'n Aantal problematiese areas in die broubedryf, wat met mout geassosieer word, is ondersoek, naamlik bierskuimkwaliteit, voortydige flokkulering van gis tydens fermentasie en die invloed van antimikrobiese faktore in mout. Die oorsaak van swak bierskuim by 'n spesifieke brouery relatief tot ander soortgelyke brouerye was geidentifiseer as die moutekstrakkookpunt tydens moutekstrakbereiding. Tydens hierdie proses ondergaan dieskuimprotein, lipiedoordrag proteien 1 (lipid transfer protein 1, LTPI), 'n konformasieverandering. Die temperature tussen 96 to 102°C was kritiek t.o.v. ideale konformasieverandering vir skuimaktiwiteit. Denaturering van LTPI het by hoër temperature plaasgevind wat die skuimproteien se aktiwitiet verminder het. Daar is ook bewys dat LTPI 'n verdere rol in bierskuim speel aangesien dit 'n lipiedbindingsproteien is wat die skuimnegatiewe lipiede verwyder. Die voorkoms van moutgeassosieerde voortydige flokkulering van gis (PYF) tydens fermentasie is op twee maniere in mout geinduseer, naamlik: • deur die toevoeging van ekstrasellulêre swamensieme tot die moutdop • deur mikrovermouting van gars in die teenwoordigheid van swamme. Die behandeling van die moutdop met kommersiele xilanase of die toevoeging van kommersiele arabinoxilaan by fermentasies het ook die flokkulering van gis beinvloed. Die hipotese was dat PYF veroorsaak is deur 'n reeks arabinoxilane met verskillende molekulêre massas wat gevorm het tydens die ensimatiese afbraakproses van die primere moutdopkomponent (arabinoxilaan). Antimikrobiese aktiwiteit teenoor brouersgis (Saccharomyces cerevisiae), ander swamme en bakterie was teenwoordig in gars, mout en moutekstrakpresipitaat. Die presipitaat bestaan uit nie-spesifieke presipitate van proteien, polifenole en lipiede wat gedeeltelik in die gekookte moutekstrak agterbly. Daar is gevind dat antimikrobiese aktiwiteit tydens vermouting toe geneem het. Die groeiproses van brouersgis, gekollekteer by 'n brouery, was geinhibeer deur die teenwoordigheid van brouery-geproduseerde moutekstrak in vergelyking met dieselfde moutekstrak wat gefiltreer was om die presipitaat te verwyder. Die brouersgis was meer sensitief heens inhibisie in vergeleke met dieselfde gisstam wat opgegroei is in die laboratorium. Verskillende S. cerevisiae stamme het ook verskille in sensitiwiteit getoon t.o.v. the antimikrobiese komponente in die moutekstrakte. 'n Verdere ondersoek het getoon dat die oorprong van die inhiberende aktiwiteit die interne dele van die gars is, asook dat dit die gissuikeropname beinvloed. Daar was egter geen direkte verband tussen antimikrobiese aktiwiteit in mout en fermentasie effektiwiteit, soos gemeet onder laboratorium toestande, nie. Hoë konsentrasies van die faktore het egter gelei tot seldood weens sellise. 'n Kationiese peptiedbevattende fraksie tussen 5 en 14 kDa en 'n optimale pH stabliliteit van 5 is gevind deur gedeeltelike karakterisering van 'n antimikrobiese moutekstrak. Die aktiewe fraksie se aktiwiteit is onomkeerbaar vernietig by ekstreme pH en blootstelling aan sekere reagense. Die aktiewe verbinding(s) is egter hittebestand en resultate het getoon dat hierdie aktiwiteit die brouproses oorleef as deel van die moutektrakpresipitaat. Voorlopige resultate van die een mout wat getoets is het die teenwoordigheid van LTP 1 getoon, asook die moontlike assosiasie met ander peptiede of kleiner komponente in die aktiewe kationiese fraksie. Die voorkoms van moutgeassosieerde PYF en antimikrobiese faktore in mout word met die mikrobiologiese kontaminasie van gars verbind. Swamme produseer die PYF faktore vanuit die moutdopkomponente, terwyl die plant weer antimikrobiese faktore produseer as deel van 'n beskermingsmeganisme teen die patogene effek van die swamme. Daar is ook 'n potensieele verwantskap tussen bierskuimproteien LTP 1 en antimikrobiese faktore in mout, aangesien LTPI ofLTPl tesame met 'n ander verbinding(s) moontlik antimikrobies is.

Thesis (M.S.)--University of California, San Diego, 2008.
Title from first page of PDF file (viewed July 25, 2008). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 28-29).

River ecosystems across the US and globally face numerous stressors that impact both ecological function and water quality. In 2015-16, municipalities along the Dan River in southern Virginia experienced repeated taste and odor (TandO) issues in their drinking water that originated from the river source water. Given that the source of TandO issues during these events were unknown, this research aimed to identify patterns in the distributions of river microorganisms that could help identify potential biological causes. Monthly water, sediment, and periphyton samples were collected for a full year from the Smith and Dan Rivers to quantify actinomycete, fungi, and chlorophyll a concentrations, which have historically been linked to TandO problems, and to characterize changes in microbial community structure. Although no significant TandO event occurred during the study period, the work produced unique and valuable data that describe patterns of microbial populations and communities in a river ecosystem. Results from the study show the abundances of actinomycetes, fungi, and chlorophyll a expressing seasonal and regional variation by habitat. From a broader ecological perspective, microbial communities sampled from water, sediment, and periphyton were each unique from each other regardless of river reach and season sampled. Overall, this research adds to our understanding of river ecology by detailing the microbial abundance and diversity in three river habitats, including periphyton, that can be used to predict sources of river TandO in future events, and offers new questions regarding how microbial diversity changes over space and time.
Master of Science
In 2015-16, cities along the Dan River in Virginia experienced multiple taste and odor (T&O) events that led to earthy and musty odors in drinking water. As part of a larger project looking at a range of possible chemical and biological sources of T&O, this research aimed to identify changes in abundance of river microorganisms that might indicate potential biological causes to T&O events. Monthly samples of water, sediment, and algal growth were collected for a year from 12 sites on the Smith and Dan Rivers. Samples were analyzed for abundances of three known T&O causing groups of organisms—actinomycetes, fungi, and photoautotrophs—and to characterize changes in total microbial communities as an indicator of ecological change occurring along the rivers. Although a significant T&O event did not occur during the study period, the research produced valuable descriptions of how important microorganisms change in a freshwater ecosystem. Actinomycetes elevated in the lower Dan River during fall, fungi elevated during the spring, and chlorophyll a was highest in the upper Smith River during winter, suggesting that photoautotrophic growth was more likely to be linked to previous T&O events. The diversity and makeup of the microbial communities in the rivers was primarily dependent on where they were growing (water, sediment, or periphyton) and secondarily on the season or the river reach. Combined, these results will help to identify causes of future T&O events in the Dan River and also provide new insights into ecological patterns of microorganisms in river ecosystems.

Anaerobic digestion is widely used for stabilization of solids in sewage sludges. Recent changes in the priorities and goals of digestion processes are focusing more attention on the efficiency of these processes. Increasing hauling cost and restrictions for land applications are two factors which are driving the increased attention to digestion efficiency. Noxious odor production from the land applied biosolids is another important issue related to digestion efficiency. Existing anaerobic digestion or aerobic digestion processes failed to provide simultaneous solution to biosolids related problems i.e. simultaneous VS reduction, better dewatering of biosolids and lesser odors from the biosolids. Studies done by Novak et al. (2004) using different activated sludges show that anaerobic-aerobic digestion and aerobic-anaerobic digestion both increase volatile solids reduction compared to a single digestion environment. They proposed that there are 4 VS fractions in sludges: (1) a fraction degradable only under aerobic conditions, (2) a fraction degradable only under anaerobic conditions, (3) a fraction degradable under both anaerobic and aerobic conditions, and (4) a non degradable fraction. It has also been found (Akunna et al., 1993) that anaerobic-aerobic sequential treatment of wastewater can help in achieving substantial nitrogen removal. These results suggest that sequential anaerobic-aerobic digestion can address multiple biosolid related problems. This study was designed to understand the effect of sequential anaerobic-aerobic digestion on the properties of resulting effluent biosolids. The study was carried out in two operation phases and during both phases one digester was maintained at thermophilic conditions and the other at mesophilic temperature conditions. In first operation phase (Phase-I) thermophilic digester was operating at 20 day SRT and mesophilic anaerobic digester was at 10 day SRT. The aerobic digesters following anaerobic digesters were operating at 6 day II SRT. In second operation phase (Phase-II), both thermophilic and mesophilic anaerobic digesters were operating at 15 day SRT and both had two aerobic digesters operating in parallel at 3 day and 6 day SRTs. In addition, batch experiments were also conducted to measure the performance of aerobic-anaerobic digestion sequence. Another study was carried out to understand the nitrogen removal mechanism during aerobic digestion of anaerobic digested sludge. The feed sludge was spiked with four different concentrations of nitrate and nitrite. It was observed during the study that aerobic digestion of anaerobic sludge helps in achieving higher Volatile solid reduction (~65% vs ~ 46% for mesophilic digestion and ~52% for thermophilic digestion). This result supports the hypothesis concerning the different fractions in volatile solids. Experimental results also show that the increase in VSR upon increasing anaerobic digestion SRT (more than 15 days) is less than the increase in the VSR due to the same increment of aerobic digestion SRT. Reduction in COD and VFA were also measured to be more than 50% during aerobic digestion. Investigation of nitrogen fate during the sequential anaerobic-aerobic digestion show more than 50% total nitrogen removal. Higher nitrogen removal was in thermophilic anaerobic â aerobic digester combination than that in mesophilic anaerobicâ aerobic combination. The most probable reason for the removal was simultaneous nitrification and denitrification. Higher concentration of readily available VFA from thermophilic anaerobic digested sludge provide advantage in denitrification in following aerobic digester. The resulting biosolids produced during sequential digestion process were also analyzed for dewatering properties and odor production. Proteins and polysaccharides concentrations were observed to decrease during aerobic digestion for thermophilic anaerobic - aerobic digestion combination, while in another combinations polysaccharide concentrations increases at aerobic phase with 3 day digestion. The concentration of polysaccharides decreases at higher digestion period of 6 and 9. The result of decrease in polysaccharide and protein was III reflected by the reduction in the polymer dose consumption and decrease in the optimum CST for the biosolids resulting from the sequential anaerobic aerobic digestion. Experimental results from odor experiments show that odor production potential of the biosolids decreases with increase in both anaerobic phase SRT and aerobic phase SRT. Thermophilic biosolids produces comparatively low odors but for longer periods, while mesophilic biosolids produces higher magnitude of odors during storage but only for comparative shorter period. Aerobic digestion of anaerobic sludge helps in reducing more than 50% odor production, but freeze-thaw cycle experiment shows that in both anaerobic and sequential anaerobic â aerobic digested sludges have higher potential for odor production. Higher aerobic digestion SRTs (6 days and above) shows more potential of reducing odors, but more experimental work is required to be done.
Master of Science

Taste-and-odor (T&O) compounds are frequently produced by cyanobacterial blooms in bodies of water. Geosmin, perhaps the most common T&O compound produced by these blooms, is not effectively removed by conventional water treatment processes and frequently causes the tap water to have an off flavor. Although geosmin is not harmful when ingested, it damages the consumers' confidence in the cleanliness of their water. There are treatment options for geosmin removal, but the most common methods are often not implemented until complaints are made by consumers.There has been an increasing amount of research on the use of polymerase chain reaction (PCR)-based methods that can detect the presence of the geosmin synthase gene which is responsible for the production of geosmin. If the geosmin synthase gene is found to be present in an emerging cyanobacterial bloom, water treatment facilities can prepare in advance to treat for geosmin. In this study, we developed a qPCR (quantitative polymerase chain reaction) assay that can detect the presence of the geosmin synthase gene in several species of cyanobacteria within the Anabaena genus. We tested our assay, as well as PCR assays designed by Giglio et al. (2008) and Suurnäkki et al. (2015) on extracted Anabaena flos-aquae DNA, biosynthesized Anabaena ucrainica DNA and DNA extracted from environmental samples of Deer Creek Reservoir, Strawberry Reservoir, and Utah Lake. It is important to note that the geosmin gene was not confirmed to be present in any of the environmental samples nor in the Anabaena flos-aquae DNA and our assay did not test positive on these samples. Our qPCR assay was very successful when used with the biosynthesized Anabaena ucrainica DNA. We used the results to estimate a DNA standard curve that can be used to estimate the starting concentration of the geosmin synthase gene. Because our assay was not successfully used with any extracted DNA, further testing and calibration may be necessary to produce a DNA standard curve that is representative of DNA that is extracted. Further calibration of the DNA standard curve was not done because there were no geosmin events during the course of the research.Development of PCR-based methods of detecting geosmin-producing cyanobacteria requires genetic sequencing information of the target-organisms. Thus, further development of PCR-based methods requires that the local geosmin-producers be identified and sequenced. Our assay as well as the assay designed by Moore (2019) can assist with the identification of these species by classifying their genus.

Thesis (MScAgric) -- Stellenbosch University, 2005.
ENGLISH ABSTRACT: Winemakers or producers are under constant pressure to reduce the operational costs for the production of wine. The reason for this being threefold: Firstly, the number of cellars and estates locally, and internationally, has grown immensely. Thus, the competition on both the national and international front has put producers under pressure to reduce their production cost in order to survive the explosion of brand possibilities on the consumer's horizons. Secondly, the exchange rate has been one of the most unpredictable variables which highlight the importance of scenario planning and sufficient financial planning in order to overcome significant exchange rate fluctuations which may cause financial strain for the business. Thirdly, the benefits of using expensive oak barrels for the maturation of premium quality wines are undisputable. These benefits include the clarification and decarbonation of wines, decrease in the astringency of tannins ("softening of tannins"), the evolution of colour, providing complementary oak aromas which increase the complexity and finesse of these wines and stabilising the colloid structure of the maturing wine. The greatest disadvantages remain nevertheless that it is a costly and labour intensive operation. Oak is an essential part of the flavour profile of many premium quality wines, and there is still a growing market demand for these wines. The use of oak barrels for the maturation of premium red wines, incorporates a specific flavour dimension to the wine (and adding value), has been the traditional way of storing wines. Well known cellars and Estates all over the world have build remarkable profiles and identities for their brands. To alter any principles regarding the use of oak will alter the style of the wines and will beyond any doubt influence their brand image negatively. Chapter 1 gives an introduction and the main aims of the study. The phenolic composition of grapes and oak are a complex mixture of different molecules which are discussed in Chapter 2. These include those responsible for the colour (anthocyanins), taste (mainly the tannins) and aroma of the wine. The composition of the oak barrel can be influenced by its origin, seasoning of the oak, toasting of the staves, age of the barrel etc. These factors all affect the chemical composition of the oak (lactones, volatile phenols, carbohydrate volatiles, hydrolysable tannins etc.) and ultimately, the wine. The chemical reactions taking place in wine during ageing are also complex, which makes maturation and research of wine in oak a complex business. The challenge, thus, developed to sustain the flavour profiles (oak attributes) and to reduce the operational costs, without influencing the identity or profile of the brand negatively. The use of oak derived products like chips, dust, blocks, staves, balls and even extracts was proposed, although it is considered by-products of the cooperage profession. Some of the major disadvantages of the use of oak derived products still remain the limited control over the production process. This may lead to inconsistency in the quality of these products. Nevertheless, the use of oak derived products and the availability of these products have grown significantly and with it a need for research on this field. Chapter 3 address the results obtained from the maturation of Pinotage, which is uniquely South African, and Shiraz wines, in different oak type barrels (French vs. American vs. Russian), as well as treatments with various oak derived products, and the influence of these oak products on the evolution of colour, phenolic development and quality of the wines during ageing. The results obtained in this project correlated with findings in the literature. The colour density, percentage of red pigment colour and S02 resistant pigments increased, especially in the first three to six months during ageing in barrels as a result of ellagic tannin extraction from the barrels and polymerisation reactions, but decreased later as maturation progresses as a result of precipitation. In some cases the use of oak increased the colour density significantly with almost 40%. The colour density, total red pigment colour and total phenolic composition decreased during bottle maturation as a result of polymerisation. No significant colour differences between the barrel types could, however, be detected. The use of oak derived products showed the same tendencies for all colour dimensions, although no significant differences could be detected between the treatments. The most significant difference was that new oak barrels contributed more to the development of colour compared to the oak treatments. The Gelatine index gives an indication of the degree of polymerisation of tannins; higher values will indicate tannins which are highly reactive and will cause an astringent mouth feel. The values should decrease as maturation progresses and tannins polymerise. Little differences between barrel types (French vs. American vs. Russian) were found in the one Shiraz, but in the two Pintage wines the index was the lowest in the wines matured in French oak after 36 months bottle ageing. Sensorial tests indicated little quality differences after 36 months between the different oak types The American oak barrels had, in general, a more "oaky bouquet", even after 36 months in the bottle. Pinotage matured with different alternative oak products showed that chips added to barrels tended to give a higher oak aroma, with a lower fruit compared to the other treatments. The same wine matured in new barrels, as expected, also had a very high oak aroma compared to the same wine matured in older barrels. This led to a higher fruit perception in the latter wines. Lees contact is a practice more commonly used in the production of white wines, but may be a dangerous practice in the production of red wines. Chapter 4 reports on the effect of lees contact during ageing of red wine on the micro flora and colour after 12 month maturation. No significant differences in microbial analysis were detected during of barrel maturation between the wines matured in the lees and the filtered wines for acetic acid, yeast and lactic acid bacteria. The initial pH differences during cold maceration and fermentation, however, did influence these numbers, with higher numbers being observed at higher pH values. However, colour differences could be detected. The concentration of yellow brown pigments (measured at 420 nm) was lower in the lees matured wines than in the filtered· wines which underwent malolactic fermentation in the barrel. Other colour differences that could be detected were higher colour density and total red pigment colour in wines as a result of longer skin contact (due to slower alcoholic fermentation rate). Thus, manipulation of the skins during alcoholic fermentation, the use of barrels and/or oak derived products in various stages of vinification and maturation of wines and additional practices as maturation on lees may be thus be used to set a certain style of wine which meet a specific market demand, trend or style. Chapter 5 summarises the results obtained and future research to be done on wood and wine. This study, however, clearly showed that the origin and oak type does not influence the colour as much as the aroma and taste of red wine under South African conditions.
AFRIKAANSE OPSOMMING; Wynmakers of produsente word onder gedurige druk geplaas om die produksiekoste van wyn te verlaag. Die redes hiervoor is drieledig: Eerstens het die getal kelders en landgoedere op nasionale en internasionale vlak geweldig toegeneem. Dus, die kompetisie op beide nasionale en internasionale gebied plaas produsente onder druk om die produksie koste van die wyn te verminder om sodoende finansieel die ontploffing van nuwe moontlike wyne op die horison van die verbruiker te oorleef. Tweedens, die wisselkoers was altyd een van die meer onvoorspelbare veranderlikes wat die belangrikheid van scenario-beplanning en weldeurdagte finansiele beplanning beklemtoon om sodoende groat veranderinge in die wisselkoers, wat moontlike finansiele druk in die besigheid mag veroorsaak, te oorkom. Derdens, een van die grootste uitgawes in die produksie proses van is die verouderingskomponent van kwaliteitswyn. Die voordele van die gebruik van eikehout vate in die verouderingsproses van rooiwyne is welbekend. Hierdie voordele sluit in die suiwering van die wyn in terme van soliede partikels , dekarbonisering (C02-ontgasting}, afname in die vrank smaak ("sagtheid van die tanniene), die ontwikkeling van die kleur van die wyn, toevoeging van komplementere hout boeketstowwe wat bydrae tot die kompleksiteit van die wyn, asook die stabilisering van die kollo"idale struktuur van die wyn. Die grootste nadeel bly, nieteenstaande, die geweldige koste verbonde aan vate, asook die hantering en onderhoud daarvan. Eike hout verwante boeketstowwe is 'n onmisbare komponent van die aroma profiel van baie kwaliteitswyne. Daar is 'n groeiende mark vir hierdie tipe wyne. Die gebruik van eikehout vate vir die veroudering van kwaliteitswyne, behalwe die bydrae van belangrike geurstowwe (een waarde), was nog altyd 'n tradisionele stap in die proses. Beroemde kelders reg oor die wereld het uitmuntende mark identiteite vir hulle self geskep, asook 'n "spesifieke identiteit" vir hulle wyn. Om enige beginsels aangaande die gebruik van eikehout te verander, sal sander twyfel die wynstyl verander en moontlik 'n negatiewe effek op die kelder se identiteit he. Hoofstuk 1 gee 'n inleiding en die hoof doelstellings van die studie. Die fenoliese samestelling van druiwe en eikehout bestaan uit 'n komplekse mengsel van verskillende molekules wat in Hoofstuk 2 beskryf word. Hierdie sluit in daardie verantwoordelik vir die kleur (antosianiene), die smaak (hoofsaaklik tanniene) en die aroma van die wyn. Die samestelling van die eikevat kan beinvloed deur die oorsprong, veroudering van die hout, roostering, ouderdom van die vat ens. Hierdie faktore beinvloed almal die samestelling van die houtvat (laktone, vlugtige fenole, hidroliseerbare tanniene ens.) en uiteindelik, die wyn. Die chemiese reaksies wat plaasvind tydens die veroudering van wyn is ook kompleks, wat die veroudering en navorsing van wyn in vate 'n komplekse proses kan maak. Die uitdaging, dus, het ontstaan om die organoleptiese profiel van die wyn (eikehout boeketstowwe) te behou en terselftertyd die produksiekoste van die wyn te verlaag. Die gebruik van eikehout verwante produkte soos skaafsels, blokkies, stawe en balke en selfs eikehout ekstrakte is aanbeveel, alhoewel dit gesien word as afvalprodukte van die kuiperye Een van die grootste nadele van eikehout alternatiewe produkte is egter die beperkte kwaliteitskontrole oor die produksieproses. Dit mag lei tot wisselvalligheid in die kwaliteit van hierdie produkte. Nieteenstaande het die gebruik van eike houtverwante produkte en die beskikbaarheid van hierdie produkte geweldig toegeneem en tesame daarmee die behoefte aan navorsing hieroor. Hoofstuk 3 bespreek resultate van die gebruik van verskillende eikehout tipe vate (Frans vs Russies vs Amerikaans), asook die gebruik van eikehout verwante produkte, op die kleur ontwikkeling, fenoliese samestelling en kwaliteit van Pinotage (eie aan Suid-Afrika) en Shiraz wyne gedurende vat en bottel veroudering. Die ontwikkeling van kleur het verskeie unieke dimensies en resultate wat verkry is in hierdie projek stem ooreen met literatuur. Die kleurdigtheid, persentasie rooi pigment en 802 weerstandbiedende pigmente het toegeneem met veroudering in houtvate (veral in die eerste drie tot ses maande) as gevolg van ellagitanniene wat geekstraeer word en gepolimerisasie, maar het later gedurende veroudering afgeneem as gevolg van presipitasie reaksies. In sekere gevalle het die kontak met hout die kleurdigtheid met tot 40% vermeerder. Die kleurdighteid, totale rooi pigmente en totale fenole het tydens bottelverouding afgeneem a.g.v. polimerisasie. Geen merkwaardige verskille kon egter tussen die verskillende vattipes gevind word nie. Verskille tussen die houtverwante produkte was ook klein en het diesefde tendense getoon as die vate. Nuwe vate se impak op die kleurprofiel en ontwikkeling van verouderde rooiwyne was egter meer beduidenswaardig as die gebruik van gebruikte vate en behandelings met eikehout verwante produkte. Die gelatien indeks verwys na die toestand van polimerisasie van tanniene. Hoer waardes kan verwag word in jong wyne en dui op hoogs reaktiewe tanniene. Die waarde sal afneem soos tanniene polimere vorm met veroudering en sal dus 'n veel minder vrank mondgevoel tot gevolg he. Klein verskille tussen die vat tipes (Frans vs Amerikaans vs Russies) is opgemerk in die een Shiraz, maar in die twee Pinotage wyne was die indeks die laagste in die wyne verouder in Franse eikehout na 36 maande se bottelveroudering. Sensoriese toetse het aangedui dat daar klein verskille gevind is tussen die verskillende eiketipes. Die wyn verouder in Amerikaanse eik het, in die algemeen, 'n sterker eikehoutkarakter gehad na 36 maande bottelveroudering. Wyn verouder met verskillende alternatiewe houtprodukte het aangetoon dat eikehouskaafels in vate 'n sterker eikehoutkarakter aan die wyn gegee het met 'n laer vrugtige aroma in vergelyking met die ander behandelings. Dieselfde wyn verouder in nuwe vate het oak, soos verwag, 'n sterk hout boeket gehad in vergelyking met die verouder in ouer vate. Dit het dan oak gelei dat laasgenoemde wyne 'n sterker vrug aroma gehad het. Veroudering van wit wyne op moer is 'n algemene praktyk, alhoewel dit minder toegepas word op rooiwyne as gevolg van verwante gevare. Hoofstuk 4 bespreek die effek van moerkontak op die mikrobiese en kleursamestelling van rooiwyn tydens 12 maande se houtveroudering. Geen noemenswaardige verskille is egter verkry tussen die wyne verouder op die moer en die filtreerde wyne vir asynsuur-, melksuurbateriee en gisgetalle nie. Aanvanklike pH verskille tydens koue masserasie en alkoholiese fermentasie het egter hierdie getalle beinvloed, met hoer ·getalle verkry in die hoer pH wyn. Die wyne wat appelmelksuurgisting in die vate ondergaan het en verouder is op die moer het egter 'n laer konsentrasie geelbruin pigmente (gemeet by 420 nm) as die gefiltreerde wyne. Ander kleurverskille sluit in hoer kleurdigtheid en totale rooi pigmente as gevolg van langer dopkontak (stadiger alkoholiese fermentasie). Manipulering van die doppe voor en tydens alkoholiese gisting, die gebruik van eikehoutvate of eikehoutverwante produkte, of kombinasies daarvan tydens verskillende produksie fases en ander praktyke soos moer kontak, kan dus gebruik word am 'n sekere styl wyn op markversoek daar te stel. Hoofstuk 5 som die resultate op, asook toekomstige navorsingsmoontlikhede wat op die gebied van hout en wyn gedoen kan word. Hierdie studie het egter duidelik aangedui dat die eikehout oorsprong en tipe die kleur nie so baie beinvloed soos die aroma en smaak van die wyn onder Suid-Afrikaanse kondisies nie.

Human senses for taste, odor, and visual assessment allow consumers to be selective when it comes to choosing their drinking water. In addition to wanting aesthetically pleasing water to drink, consumers want to know if their water is safe and may have misconceptions on what possible health risk contaminants could be lurking in their water supply. This thesis aimed to measure reaction of zerovalent nanoiron (nZVI) in water and human saliva, evaluate consumer's perceptions of taste, odor, and risk in their drinking water, and investigate the effectiveness of community water systems in communicating water quality information to their consumers. Since nZVI, including commercially available Nanofer 25S, is widely being used in water treatment processes and has future potential for use in fortifying foods, the exposure to these engineered nanoparticles will increase for humans and aquatic organisms. Thus, the first part of the thesis was to develop a quantitative analytical technique to measure the iron levels at environmentally relevant concentrations. Researchers developed a colorimetric assay using 1, 10-phenanthroline as an assay to determine the amount of ferrous ions produced from different iron materials, including ferrous(II)sulfate, nZVI, and goethite. Resulting ferrous ion measurements indicate that the maximum production of ferrous ions varied among the iron materials. Nanofer25S did not undergo 100% conversion to ferrous ions, as expected, goethite had no production of ferrous ions, and ferrous(II)sulfate was 100% ferrous ions. The total iron, as measured by atomic absorption for all iron materials were equal. The reactivity of these iron materials were also assessed in different water qualities ranging in salt concentrations. The capacity to produce ferrous ion did not change when added to nanopure water, tap water, and inorganic solution that is equivalent to the high ionic strength of saliva. Toxicology data for nZVI exposure to humans and aquatic organisms are limited. For that reason, authors of this manuscript measured salivary lipid oxidation (SLO) potential for the different iron materials in human saliva. They also developed an artificial saliva recipe to ensure repeatability and comparable results among laboratories due to human saliva's variability day by day. This simulated human saliva contained salts, proteins, and lipids. Using thiobarbituric acid reactive substances (TBARs), both Nanofer25S and ferrous(II)sulfate induced in-vitro SLO with human saliva. Goethite was unreactive. SLO results from this study have implications for flavor effects of nZVI in drinking water. The second chapter of this thesis is assessing the clarity of message communication of Consumer Confidence Reports (CCRs). In 1998, the United States Environmental Protection Agency (USEPA) mandated that community water systems (CWSs) provide annual water quality reports to their consumers. These CCRs summarize information regarding water sources, any detected contaminants, compliance with federal regulations, and educational information. Thirty CCRs across all ten USEPA regions were analyzed for clarity using the Centers for Disease Control and Prevention's (CDC) Clear Communication Index (CCI) tool. The analysis of these CCRs was a national representation of CWSs and revealed that currently distributed CCRs performed poorly on the CDC's CCI—all failing to meet the 90% passing mark. The overall average score for all CCRs was 50.3 ± 13.5%. The clarity scores were based on seven key areas: 1) Main message and call to action; 2) Language; 3) Information design; 4) State of the science; 5) Behavioral recommendations; 6) Numbers; and 7) Risk. Improvements in all seven areas—with the lowest average scores at 3.3 ± 18.1%, 21.7 ± 26.6%, and 37.7 ± 27.1%, respectively, for state of science, language, and main message and call to action—of the CCI will greatly improve the quality and educational capabilities of CCRs. The failing scores highlight the challenges facing CWSs in communicating water quality information. This assessment can serve as a tool for water utilities to effectively prepare and distribute information to their consumers in the future. CWSs must promote a two-way dialogue with their consumers. They should address consumer's concerns and wants in the CCRs, and they should also effectively communicate risks to the consumers so that they are not under the misconception that their water is unsafe to drink. CWSs should use the CCRs as a way to educate the public and promote drinking tap water. The last chapter of this thesis addresses the concerns that consumers may have about their drinking water and methods that could be implemented to quickly and efficiently respond to consumer complaints and contaminants with sensory properties. Just like CWSs, consumers are concerned about their water; they are the sentinels to water quality monitoring because they are uniquely positioned at the tap. Consumers are able to detect the slightest taste, odor, and appearance in their drinking water because it is well—instinctive! Thus, consumer feedback and complaint data provided to a utility should be taken seriously and stored for future comparisons. Any consumer complaint represents a fruitful data stream that should be harnessed routinely to gain knowledge about aesthetic water quality in the distribution system. Four utilities provided consumer complaints on water quality data that were categorized and visualized using radar and run-time plots. As a result, major taste, odor, and appearance patterns emerged that clarified the issue and could provide guidance to the utilities on the nature and extent of the problem. Consumer complaint data is valuable for water quality issue identification, but CWSs should understand that even though humans readily identify visual issues with water, such as color, cloudiness, or rust, describing specific tastes and particularly odors in drinking water is acknowledged to be a much more difficult task for humans to achieve without training. This was demonstrated with two utility groups, laboratory personnel and plant operators, and a group of consumers identifying the odor of orange, 2-MIB, and DMTS. All of the groups were able to identify the familiar orange odor. However, the two utility groups were much more able to identify the musty odor of 2-MIB; this may be due to the fact that the utility groups are more familiar with raw and finished water. DMTS, a garlic-onion odor associated with sulfur compounds in drinking water, was the least familiar to all three groups. The lab personnel group was the better describers of the odor, but the results within this group still varied significantly. These results suggest that utility personnel should be mindful of consumers who complain that their water is different, but cannot describe the problem. To reduce the inability to describe an odor or taste issue, a TandO program at a utility can be beneficial. The safety and aesthetic characteristics of drinking water is most important to consumers. They both complement each other; if consumers think their water tastes funny, they would probably assume that is unsafe to drink. Since nZVI is increasingly being introduced into the drinking water supply, researchers must be able to understand how it reacts in humans and the environment. Additionally, CCRs would be an effective method for CWSs to communicate water quality information and address any concerns consumers may have about their water. CWSs can use implement the radar and run-time plots to identify issues in the drinking water systems. Also, TandO programs will allow CWSs and their consumers to better describe and identify the issues in their drinking water as it arises so that it can be easily addressed and alleviated. Thus, promoting communication between water utilities and their consumers will improve the relationship and instill confidence in consumers about their drinking water.
Master of Science

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.

Generation of hydrogen sulfide (H2S) is a common phenomenon from wastewater collection, transport, and treatment processes. Impacts of H2S emissions from wastewater include corrosion and reduction in the service life of wastewater infrastructure, odor nuisance in the community, and health impacts on wastewater operations and maintenance personnel (Neilsen, et al. WEFTEC 2006). Conventional odor control studies performed by municipalities to design their individual odor/corrosion control strategies largely depend on establishing a dilution to detection threshold (D/T) ratio and ascertaining the recognition threshold (R/T) for air samples collected from the study area. These conventional odor studies based on grab samples using R/T and D/T technique using a few days of data have a number of limitations and potentially lead to inaccurate conclusions. However, H2S emission studies using continuous air monitoring is expensive and time consuming. The objective of this research is to understand the feasibility of utilizing emission factors as a tool to predict hydrogen sulfide emissions from headworks of four different Jefferson Parish, Louisiana wastewater treatment plants (WWTP). Proposed model(s) developed for predicting H2S emission factors that depend on wastewater parameters should be convenient for the municipalities to use as the data required is monitored routinely. Use of H2S emission models should assist rapid identification of H2S emission hot spots, optimize H2S control strategies, predict potential health risks, prevent community odor nuisance, and ascertain infrastructure corrosion. This dissertation attempts to; i) develop a research methodology, ii) identify instruments required, iii) generate emission factor ranges and compare their sensitivity to wastewater parameters, iv) generate preliminary empirical emission models based on flow treated, population serviced and area served by a treatment plant for each sampling location and v) provide a roadmap for future research opportunities to refine the models generated as part of this dissertation. Key words: emission model, emission factor, emission ranges, hydrogen sulfide, odor control, air quality, wastewater treatment.

Avalia a alteração da qualidade da água da região de lançamento dos efluentes domésticos no reservatório de Três Irmãos, em virtude da aplicação de nitrato de amônio, para controle de odor, na rede coletora de esgotos do município de Pereira Barreto desde 1996. Foram realizadas 6 campanhas, com freqüência bimestral, no período de Outubro de 2004 a Agosto de 2005. As amostras foram coletadas em seis pontos, sendo cinco no reservatório, e um na ETE-Pereira Barreto. Em cada estação no reservatório, as amostras foram tomadas à superfície, à meia profundidade e fundo. Obtiveram-se amostras de água e esgoto para análise de parâmetros físicos, químicos e hidrobiológicos. Para melhor avaliar a qualidade da água, como também do efluente final da ETE, foram efetuados o Teste de Postos com Sinais de Wilcoxon para Pares Combinados (Método Não-Paramétrico), Análise de Componentes Principais (ACP) e Análise de Agrupamento (Cluster). Os resultados mostraram que os níveis de nitrogênio nitrato na água e no efluente final situaram-se bem abaixo do limite máximo estabelecido pelo CONAMA 357/05 para águas da Classe 2 (10 mg/L). Concluiu-se que a prática da adição de nitrato de amônio para reduzir os odores em rede coletoras de esgotos sanitários, sob o ponto de vista ambiental, não apresentou potencial para acarretar impacto negativo no corpo receptor, e que a região de estudo no reservatório é um ambiente bem oxigenado, inclusive nas camadas mais profundas, com baixos teores de turbidez e pH levemente alcalino,entretanto, com alta condutividade elétrica e elevadas concentrações de nutrientes (fósforo e amônia), principalmente no período de verão. Este fato é devido à influência principalmente do esgoto doméstico que é lançado nesta área.
It evaluates the alteration of the quality of the water in the region of discharges of domestic effluents into the Três Irmãos reservoir, due to the application, since 1996, of ammonium nitrate into the sewer system of the city of Pereira Barreto. Six trips to collect samples were performed bimonthly between October 2004 and August 2005.The samples were collected at six different points: five in the reservoir and one in the Sewage Treatment Plant in Pereira Barreto. In each station of the reservoir, the samples were collected on the surface, at half depth and at the bottom. Water and sewage samples were obtained for analysis of physical, chemical and hydrobiological parameters. In order to better evaluate the quality of water, as well as the quality of the final effluent from the sewage of the Sewage Treatment Plant, the Wilcoxon Signed-rank Test for Paired Data (Nonparametric Test), the Principal Component Analysis and the Hierarchical Cluster Analysis Methods were performed. The results showed that the levels of nitrate-nitrogen in the water and in the final effluent were way below the maximum limit established by CONAMA 357/05 for Class 2 waters (10 mg/L). It was concluded that, environmentally speaking, the addition of ammonium nitrate to reduce the odors in sanitary sewer systems was not potentially significant to cause a negative impact on the reservoir. It was also concluded that the region under study in the reservoir is well oxygenated, even in deeper layers, with low turbidity levels and slightly alkaline pH; however, high electrical conductivity and high concentrations of nutrients (phosphorus and ammonia) were observed, mainly in summer. This is mainly due to the influence of the domestic sewage which is discharged in that area.

This thesis deals with machine learning techniques for the extraction of structure and the analysis of the vertebrate olfactory pathway based on related methods. Some of its main contributions are summarized below. We have performed a systematic investigation for classification in biomedical images with the goal of recognizing a material in these images by its texture. This investigation included (i) different measures for evaluating the importance of image descriptors (features), (ii) methods to select a feature set based on these evaluations, and (iii) classification algorithms. Image features were evaluated according to their estimated relevance for the classification task and their redundancy with other features. For this purpose, we proposed a framework for relevance and redundancy measures and, within this framework, we proposed two new measures. These were the value difference metric and the fit criterion. Both measures performed well in comparison with other previously used ones for evaluating features. We also proposed a Hopfield network as a method for feature selection, which in experiments gave one of the best results relative to other previously used approaches. We proposed a genetic algorithm for clustering and tested it on several realworld datasets. This genetic algorithm was novel in several ways, including (i) the use of intra-cluster distance as additional optimization criterion, (ii) an annealing procedure, and (iii) adaptation of mutation rates. As opposed to many conventional clustering algorithms, our optimization framework allowed us to use different cluster validation measures including those which do not rely on cluster centroids. We demonstrated the use of the clustering algorithm experimentally with several cluster validity measures as optimization criteria. We compared the performance of our clustering algorithm to that of the often-used fuzzy c-means algorithm on several standard machine learning datasets from the University of California/Urvine (UCI) and obtained good results. The organization of representations in the brain has been observed at several stages of processing to spatially decompose input from the environment into features that are somehow relevant from a behavioral or perceptual standpoint. For the perception of smells, the analysis of such an organization, however, is not as straightforward because of the missing metric. Some studies report spatial clusters for several combinations of physico-chemical properties in the olfactory bulb at the level of the glomeruli. We performed a systematic study of representations based on a dataset of activity-related images comprising more than 350 odorants and covering the whole spatial array of the first synaptic level in the olfactory system. We found clustered representations for several physico-chemical properties. We compared the relevance of these properties to activations and estimated the size of the coding zones. The results confirmed and extended previous studies on olfactory coding for physico-chemical properties. Particularly of interest was the spatial progression by carbon chain that we found. We discussed our estimates of relevance and coding size in the context of processing strategies. We think that the results obtained in this study could guide the search into olfactory coding primitives and the understanding of the stimulus space. In a second study on representations in the olfactory bulb, we grouped odorants together by perceptual categories, such as floral and fruity. By the application of the same statistical methods as in the previous study, we found clustered zones for these categories. Furthermore, we found that distances between spatial representations were related to perceptual differences in humans as reported in the literature. This was possibly the first time that such an analysis had been done. Apart from pointing towards a spatial decomposition by perceptual dimensions, results indicate that distance relationships between representations could be perceptually meaningful. In a third study, we modeled axon convergence from olfactory receptor neurons to the olfactory bulb. Sensory neurons were stimulated by a set of biologically-relevant odors, which were described by a set of physico-chemical properties that covaried with the neural and glomerular population activity in the olfactory bulb. Convergence was mediated by the covariance between olfactory neurons. In our model, we could replicate the formation of glomeruli and concentration coding as reported in the literature, and further, we found that the spatial relationships between representational zones resulting from our model correlated with reported perceptual differences between odor categories. This shows that natural statistics, including similarity of physico-chemical structure of odorants, can give rise to an ordered arrangement of representations at the olfactory bulb level where the distances between representations are perceptually relevant.

QC 20120224

CAPES
Garantir a qualidade de produtos alimentícios como óleos vegetais é de grande importância para indústrias e pesquisas relacionadas à área de alimentos. Óleos vegetais podem ter sua composição adulterada ou suspeita devido à presença de outros óleos de menor valor comercial. Além disso, problemas relacionados à conservação durante o armazenamento, como, o desenvolvimento de ácidos graxos de cadeia curta e ácidos graxos livres, podem ser desencadeados por processos de degradação. Alterações na composição de óleos podem ser detectadas a partir do uso de cromatografia, enquanto técnicas titulométricas como índice de acidez e saponificação auxiliam na verificação da estabilidade durante a cadeia de distribuição e consumo. Essas técnicas aliadas à espectroscopia e a métodos de análise estatística multivariada permitem, portanto, determinar a qualidade e realizar a discriminação de óleos vegetais. Foram utilizadas 38 amostras de óleos vegetais sendo: 10 de óleo de soja, 6 de milho, 6 de girassol, 6 de canola, 9 azeites de oliva extra virgem e 1 óleo misto de soja e canola. Foram obtidas as composições em ácidos graxos utilizando-se cromatografia gasosa com detector de ionização de chama, índice de acidez, índice de saponificação e índice de iodo de acordo com as metodologias propostas pela Amerian Oil Chemists Society e foram obtidos os espectros na região do infravermelho médio utilizando-se a espectroscopia no infravermelho com transformada de Fourier. A partir dessas análises obteve-se, portanto, três tabelas de dados (cromatográficos, físico-químicos e espectroscópicos) que, por sua vez, foram submetidos à análise estatística. Análise de componentes comuns e pesos específicos foi aplicada às tabelas de dados para discriminação e avaliação da qualidade das amostras. Amostras apresentaram índice de acidez e saponificação elevado em relação a outros estudos. Óleos de soja, milho e girassol possuem maior teor de ácidos graxos polinsaturados, principalmente ácido linoleico em sua composição, enquanto óleos de canola e azeites de oliva extra virgens apresentam maior teor de ácidos graxos monoinsaturados como ácido oleico. A espectroscopia no infravermelho médio permitiu observar a presença de bandas intensas de absorção demonstrando a presença de grupamentos específicos de ácidos orgânicos como estiramento de carbonos unidos por ligações duplas como isômeros cis, metil e metileno, bandas relacionadas à carbonilas dos triacilgliceróis e ausência de ácidos graxos trans por não apresentarem absorções em 3025 e 968 cm-1. A partir da análise de componentes comuns e pesos específicos foi possível separar os dados em três dimensões comuns contendo 56,44, 34,74 e 8,77% da variância dos dados, as quais foram influenciadas majoritariamente pelas análises cromatográficas, físico-químicas e espectroscópicas, respectivamente. De acordo com o perfil de agrupamento das amostras foi possível realizar a discriminação das amostras em relação às matrizes de extração e observado ausência de adulterações. Cromatografia gasosa foi essencial na discriminação das amostras, análises físico-químicas na avaliação da qualidade enquanto os dados espectroscópicos apresentaram baixa influência nos dados, não colaborando efetivamente para a discriminação das amostras. Por fim, análise de componentes comuns e pesos específicos pode ser aplicada de forma eficaz na discriminação de óleos vegetais.
Ensure the quality of food products such as vegetable oils have great importance to industry and researches related to food. Vegetable oils can have their composition adulterated or suspected due to the presence of other oils with lower commercially value. In addition, problems related to preservation during storage as the development of short chain and free fatty acids can be initiated by degradation processes like rancidity. Alterations in composition can be detected by the use of chromatography while titrimetric techniques assists in the verification of stability during storage. These techniques combined to spectrocopy and multivariate statistical methods allow determine the quality and realize the discrimination of vegetable oils. 38 samples of vegetable oils were used being: 10 soybean, 6 corn, 6 sunflower, 6 canola, 9 extra virgin olive oil and 1 mixed canola and soybean oil. It was obtained the fatty acid composition using gas chromatography (GC-FID), acid, saponification and iodine value according to American Oil Chemists Society methods and the spectra in the mid-infrared region were obtained using Fourier transform infrared spectroscopy. From these analyses it was obtained three data tables (chromatographic, physicochemical and spectrocopic) that, in its turn, were submitted to statistical analysis. Common components and specific weights analysis were applied to the data tables to discrimination and evaluation of the quality of samples. Samples presented acid and saponification values high in relation to other studies. Soybean, corn and sunflower oil have higher contend in polyunsaturated fatty acid, mainly linoleic acid in their composition while canola and extra virgin olive oils presented higher amount of monounsaturated fatty acids as oleic acid. The mid-infrared spectrocopy permitted observe the presence of intense absorption bands demonstrating the presence of specific groups of organic acids like carbon stretch united by double bonds with cis isomers, methyl and methylene, bands related to carbonyls of triacylglycerols and the absence of trans isomers by not present absorptions in 3025 and 968 cm-1. From common components and specific weights analysis was possible separate data in three common dimensions containing 56,44, 34,74 and 8,77% of the data variance which were influenced mainly by chromatographic, physicochemical and spectroscopy analyses, respectivetly. According to the cluster profile of the samples was possible to realize the discrimination of the samples in relation to the extraction matrices and it was observed the absence of adulterations. Gas chromatography was essential to the discrimination and physicochemical analyses to the evaluation of the quality of the samples while the spectrocopic data presented low influence to the data, not contributing effectively to the discrimination of the samples. At last, common components and specific weichts analysis can be applyed efficiently to discrimination of vegetable oils.

Master of Science
Food Science
Delores H. Chambers
Tools are available, through various reference books, to develop a purposeful sensory quality program. Some companies already have a strong sensory program in place; others may require a cultural change to facilitate the implementation. This paper indicates some of the challenges to be overcome, covers some current quality control (QC) sensory practices and addresses advantages and disadvantages of expert tasters Some specific issues regarding sensory evaluations of alcohol beverages are discussed and critical factors in production are reviewed with discussion on the potential for off taint development.

In recent years, communities that source raw water from the Dan River experienced two severe and unprecedented outbreaks of unpleasant tastes and odors in their drinking water. During both TandO events strong 'earthy', 'musty' odors were reported, but the source was not identified. The first TandO event began in early February, 2015 and coincided with an algal bloom in the Dan River. The algal bloom was thought to be the cause, but after the bloom dissipated, odors persisted until May 2015. The second TandO in October, 2015 did not coincide with observed algal blooms. On February 2, 2014 approximately 39,000 tons of coal ash from a Duke Energy coal ash pond was spilled into the Dan River near Eden, NC. As there were no documented TandO events before the spill, there is concern the coal ash adversely impacted water quality and biological communities in the Dan River leading to the TandO events. In addition to the coal ash spill, years of industrial and agricultural activity in the Dan River area may have contributed to the TandO events. The purpose of this research was to elucidate causes of the two TandO events and provide guidance to prevent future problems. Monthly water samples were collected from August, 2016 to September, 2017 from twelve sites along the Dan and Smith Rivers. Multivariate analyses were applied to look for underlying factors, spatial or temporal trends in the data. There were no reported TandO events during the project but sensory analysis, Flavor Profile Analysis, characterized earthy/musty odors present. No temporal or spatial trends of odors were observed. Seven earthy/musty odorants commonly associated with TandO events were detected. Odor intensity was mainly driven by geosmin, but no relationship between strong odors and odorants was observed.
Master of Science

Der Beitrag geht (in Abschnitt I) von zwei allgemeinen Ununterrichtbarkeitsthesen zu der Frage aus, ob und wie ‚Klassik‘ in der Schule unterrichtet werden kann, und entfaltet einen Lösungsansatz aus einer Perspektive ästhetisch-kultureller Edukation, der es darum geht, verschiedene musikalische Praxen erfahrbar zu machen. Die Grundannahmen dieser Perspektive werden in Abschnitt II zusammenfassend dargstellt. Das Wort „außeraustralisch“ soll eine kulturelle Außenperspektive auf die europäische Klassik signalisieren. Im Zentrum des Beitrags (Abschnitt III) steht eine „didaktische Interpretation klassisch-romantischer Musikkultur“, der es um die Formulierung charakteristischer Qualitäten dieser Musik bzw. Musikkultur geht. Als exemplarisch für deren Nachvollziehen erscheint eine Entwicklung von informeller über konventionalisierte und halböffentliche Hausmusik hin zum Konzert. Die entsprechenden Erfahrungsqualitäten bilden den Angelpunkt für die Gestaltung der Unterrichtspraxis. Mit drei abschließenden Inszenierungsskizzen für charakteristische Qualitäten (Abschnit IV) macht der Text einen Schritt weg von der wissenschaftlich geleiteten Analyse hin zur ästhetisch interpretierenden Gestaltung. Insgesamt stellt der Beitrag am Beispiel der Klassik exemplarisch ein allgemeines musikpädagogisches Herangehen dar
The article starts (in part I) from two theses about the impossibility of teaching classical music in the classroom and shows a solution to do so. Part II outlines the actual perspective, which is based on music and music education as and for aesthetical and cultural practice. The word “außeraustralisch” (out of australia) indicates a perspective at classical music from a foreign point of view. The crucial part III claims “characteristic qualities” as the main reference point to stage musical practice in the classroom and developes characteristical qualities of classical-romantic music in a “didactic interpretation of classical-romantic culture of music”. The development from an informal to a conventionalized and half public Hausmusik up to public concerts appears to be generic to comprehend special attitudes and concepts of this kind of music. Part IV goes one step further towards an aesthetical interpretation of classical music as it creates three drafts, which outline how to stage music in such a way, that makes characteristic qualities of classical music perceptible in the classroom. Altogether the article uses the classical music in the classroom as an exemple for a general music pedagogical approach

A preliminary trial to determine the effect of repeated freezing and thawing on beef striploins, showed that the effect of thawing on frozen non-aged beef significantly improved tenderness, flavour and acceptability, indicating that thawing had a similar effect to aging. In the subsequent study, 207 beef striploins were collected from the Southern Crossbreeding Project (SXB: 70 heifers grainfed for 80 days, 70 steers grainfed for 180 days), Davies Gene Mapping Project (DGM: 30 steers grainfed for 180 days) and also 37 Hanwoo striploins imported into Australia from Korea. SXB animals consisted of Hereford cross calves sired by Belgian Blue, Limousin, South Devon, Hereford, Angus, Wagyu and Jersey bulls. DGM animals consisted of purebred Limousins and Jerseys and Limousin by Jersey crosses. Sensory analysis of beef striploins involved semi-trained taste panel assessments, using nine-point category scales for initial and sustained juiciness, beef flavour, beef fat flavour, oily flavour, buttery flavour, chicken-skin flavour, corn flavour, grassy flavour and overall acceptability. Flavour acceptability was positively enhanced by increased levels of intramuscular fat (IMF%). Significant differences in breed were apparent for juiciness, beef flavour, buttery flavour and flavour acceptability, after adjusting data to a constant level of intramuscular fat, suggesting that some variation in flavour may be genetic. The Korean Hanwoo displayed a numerically higher intensity of chicken score and lower intensity of beef flavour. Australian cattle breeds differed in fatty acid composition between each other and also to that of the Korean Hanwoo. The latter had 57% mono-unsaturated fatty acids, which was significantly higher (P<0.001) than the Australian breeds (47%). Since IMF% was confounded with breed, breed differences were not significant when adjusted for IMF%. Jersey animals most closely resembled the Hanwoo in fatty acid profile, whilst animals containing Limousin differed markedly from the Hanwoo. A chemical sensor was able to establish significant differences between Korean Hanwoo and Australian animals and predominantly mirrored differences in fatty acid composition and to some extent flavour. Development of prediction equations from individual fatty acids was disappointing (R2< 15%). However, when fatty acid data, IMF% and chemical sensor data were combined to form prediction equations, moderate R2 values were obtained of (24% to 43%).
Thesis (M.Ag.Sc.)--School of Agriculture & Wine, 2001.

The aim of the study was to analyze quality of investigation and treatment in the specialized services – dermatological and sexually transmissible diseases outpatient department of the II Kaunas Clinical hospital and private health care institution “Medidermas”. Methods. Study population – patients with dermatological and sexually transmissible diseases. Randomly selected patients were interviewed in 2004 September-October. Totally 157 patients from state and 62 from private institution were investigated. MS Office Exel and EpiInfo 6.0 packages were used in the statistical analysis. Results. Mean age of the investigated was 42.5±1.1 yrs. One quarter of the investigated chose health care institution, recommended by familiar or friend, only 24% applied to specialized departments with referrals. The majority of respondents (85.5%) of the private institution “Medidermas” were accepted after few days of registration, 38.2% (p<0.001) of the dermatological and sexually transmissible diseases outpatient department of the II Kaunas Clinical hospital were accepted after one or two weeks. 45.2% of the investigated in the private service were registered in the interval of 10 minutes, 43.5% - 15 minutes. In the state institution only 17.8% (p 0.001) were registered during 10 minutes and half – 15 minutes. The respondents of “Medidermas” had a longer waiting time before acceptance to a medical doctor as compared to the state health care service (in 10 minutes 41.9% and 17.3%, p<0.001... [to full text]

Thesis (MSc)--Stellenbosch University, 2013.
ENGLISH ABSTRACT: Nitrogen composition of grape must is highly variable and impacts on the health of the fermenting yeast population as well as the formation of aroma and flavour compounds in wine. Insufficient yeast assimilable nitrogen (YAN), mostly consisting of amino acids and ammonium, can lead to stuck or sluggish fermentations as well as the formation of undesirable compounds such as H2S. Furthermore, it is well established that the total concentration of YAN and the specific amino acid composition have a significant impact on the final aroma and flavour of wines. However, the impact of individual amino acids and of specific amino acid compositions on fermentation kinetics and on the production of aroma and flavour impact compounds under winemaking conditions is not well understood. The first goal of this study was to evaluate the effect of single amino acids on growth kinetics and major volatile production of two industrial wine yeast strains under conditions resembling wine fermentations. To facilitate these fermentation conditions while also allowing for easy reproducibility and manipulation of the initial components, a synthetic grape media was utilized. Biomass formation, exponential growth rate, lag phase, and fermentation duration were utilized to evaluate the efficiency of single amino acids. The data show that previously observed trends in laboratory strains mostly apply to these conditions and strains. In general, the efficiency of amino acids to be used as nitrogen sources and the production of major volatiles due to their presence followed the same patterns for both industrial yeast strains. However, the production of the secondary metabolites butanol, propanol, acetic acid, and ethyl acetate were found to be produced in different final concentrations dependent upon the yeast strain. The branched-chained and aromatic amino acids (BCAAs) treatments were observed to have the most dramatic effects on major volatile production. Investigating the relationships between the initial concentration of the BCAAs and the final concentrations of major volatile compounds, it was found that the production of fusel alcohols and fusel acids due to the degradation of BCAAs by S. cerevisiae could be predicted from the initial concentration of BCAAs. While under simple nitrogen conditions the production of several other secondary metabolites such as butanol, propionic acid, valeric acid, decanoic acid and 2-phenylethyl acetate were found to be correlated to the initial concentration of BCAAs in the media. Future studies should focus on the validation of these trends in aroma production in real grape musts under various fermentation temperatures for a number of industrial wine yeast strains.
AFRIKAANSE OPSOMMING: Die stikstof samestelling van druiwemos is hoogs veranderlik en impakteer op die kerngesondheid van die fermenterende gis populasie asook die produksie van aroma- en geurverbindings in wyn. Onvoldoende assimileerbare stikstof (ook genoem “yeast assimilable nitrogen” (YAN)), wat meestal bestaan uit aminosure en ammonium, kan aanleiding gee tot steek- of slepende fermentasies, asook die vorming van ongewensde verbindings soos H2S. Dit is alombekend dat die totale konsentrasie van YAN en dan ook die spesifieke aminosuur samestelling ‘n noemenswaardige impak op die finale aroma en smaak van wyn het. Die invloed van individuele am inosure en spesifieke aminosuur samestellings op die fermentasie kinetika, asook die produksie van verbindings met ‘n impak op die wyn aroma en smaak, word egter nie deeglik verstaan nie. Die eerste doelwit van die studie was om twee industriële gisrasse te gebruik om die effek van enkel aminosure op die groei-kinetika en produksie van die vername vlugtige verbindings onder wynmaak toestande te bepaal. Kunsmatige, gedefinieerde druiwermosmedium is gebruik om wynmaak toestande te simuleer en ook herhaalbaarheid en manipulering van die aanvanklike samestelling van die medium te verseker. Die studie het vorige tendense wat opgemerk is in die evaluasie van laboratorium rasse onder soortgelyke toestande bevestig. Die doeltreffendheid waarmee aminosure oor die algemeen gebruik word as stikstofbron, asook die produksie van die vernaamste vlugtige verbindings wat gekoppel is aan hulle teenwoordigheid, het ‘n vergelykbare patroon vir beide rasse gevolg. Die sekondêre metaboliete butanol, propanol, asetaat en etiel-asetaat is egter wel in verskillende eindkonsentrasies geproduseer deur die verskillende gisrasse. Die vertakte-ketting en aromatiese aminosuur (“branched-chained and aromatic amino acids” (BCAAs)) behandelings het die mees dramatiese effek op die produksie van die vernaamste vlugtige komponente gehad. Ondersoek na die verwantskap tussen die aanvanklike konsentraies van die BCAAs en die finale konsentrasies van dié verbindings het aangedui dat die produksie van hoër alkohole en sure, as gevolg van die afbraak van BCAAs deur S. cerevisiae, met behulp van die aanvanklike konsentrasie van die BCAAs voorspel kon word. Terselfdertyd is gevind dat onder eenvoudige stikstoftoestande, verskeie ander sekondêre metaboliete soos butanol, propionaat, valeriaat, dekanoësuur en 2-fenieletielasetaat, gekorreleer kan word met die aanvanklike BCAAs in die media. Verdere studies moet poog om hierdie tendense ten opsigte van aromaproduksie te bevestig en wel deur gebruik te maak van ware druiwemos, verskeie fermentasietemperature, asook ’n verskeidenheid van wyngisrasse.

碩士
嘉南藥理大學
環境工程與科學系
105
Fishery feedstuff are made of lower-classed fishes with less economic or the rinsing of seafood or freshwater products. Within the procedure of cooking, liquid and solid separation, and drying, the emission of the dryer machine, containing trimethylamine and other odorous gas or substances, usually are the major sources of the odor and have been a public concern. The neighbors living around the fishery feedstuff plant always complain the bad smell and odor could reduce the environmental quality. The aims in this study was to find out and measure the emission sources of the odor and fine particle during the procedure of manufacturing fishery feedstuffs. Analyzing the procedure of manufacturing fishery feedstuffs, the odor and particulate matters in 6 locations such as raw warehouse, well-package house, blending procedure, and business office in factory, the position about 100 to 200 meters away from the upwind and downwind of plant also were sampled individually. In case of this study, each location had various odor concentration within 3 different working time, the average odor value was 256 at blending procedure, 194 at raw warehouse and 114 at well-package house. The odor standard around ambient air is 30 at industrial and agricultural area. It is obvious that this fishery feedstuff plant should consider the available control technology or devices to reduce the odor emission to improve the troubled pollution.

碩士
國立成功大學
環境工程學系碩博士班
96
The odor is often one of the water quality questions that the people’s concern in the drinking water. This research can be divided into two parts mainly, one part main investigated the musty odor in the reservoir. We used the actinomyces which were screened in the sediment of Cheng-Chin reservoir in 2006 and collocated the 2K factor-design to simulate the water condition (include pH, carbon source, nitrogen source, and temperature) to further seek the main factors of influencing the odor-producing efficiency; The another part we selected the Bacillus that separated from our laboratory and enrichmented with different medium to investigate the odor-compounds degradation efficiency of this bacteria. The results indicated that S31 and S32 has the significant efficiency of odor-producing. After 7 days, the concentration of 2-MIB and Geosmin could up to 715.7 and 4113.4ng/L, respectively.The concentration of Geosmin were all lower than the concentration of 2-MIB, and the bacterial S32 has better odor-producing ability than S31. After transferring with ANOVA software we found the temperature, pH and the concentration of ammonium carbonate were the main factors by influencing odor-producing efficiency. In the biodegradated tests, we found the efficiency increased with increasing the concentration of cometabolism substrate and the degradation efficiency of 2-MIB is much better than Geosmin. The best degradation time was 9 days, and test bacterial B-1 and B-2 could degrade 2-MIB calculated to 39.3ng/L and 45.7ng/L with initial concentration were 100ng/L, respectively. The degradation efficiency are 60.72% and 54.33%. After the preliminary degradation test, the residual Geosmin concentration were 90.2ng/L and 95.4ng/L, and the degradation efficiency were less than 10%. In the biodegradation experiments, when the conditions were pH=7.0, nitrate source=NH4NO3, temperature=35℃, the degradation efficiency of 2-MIB can be up to over 80%. After transforming the effects via ANOVA software, we found pH value, nitrogen source, temperature were the main factors of biodegradation of odor compounds.

碩士
國立中山大學
環境工程研究所
102
This study measured Ambient concentrations of air pollutants, ammonia and Volatile Organic Compounds (VOCs) in industrial park in Southern Taiwan. The spatial distribution was investigated during different time periods and seasons. Use odor threat value( OTV), ie the ratio of species detectable concentration and their odor threshold to investigate the odor species and emission sources in industrial park. Also, this study measured odor and VOCs concentration in odor occur area. Investigate the possible odor characteristics, species and sources. The season distribution of air pollutants showed concentration in winter higher than summer, due to low atmospheric mixing layer height in winter caused poor diffusion effects of pollutants. In contrast, exuberant convection in summer resulted in lower air pollutant monitoring values. The time period distribution showed the results which PM10, CO, NOX and SO2 concentrations occurred peaks during high traffic period (6:00–10:00 and 17:00–20:00). The concentration of O3 as a high vaiue during daytime(10：00–18：00), at night fell to a low value. The concentrations of THC, CH4 and NMHC had no significant diurnal variation. The index pollutant of air quality was PM10, which the largest emissions source was vehicle dust, showed a significant impact on mobile sources of air quality in industrial park. The concentrations of ammonia between 0.012–0.098 ppm, far below the regulatory standards (1 ppm) and ammonia odor threshold (1.5 ppm), showed ammonia did not cause odor in industrial park. The characteristics of VOCs impact on odor showed detection species in low odor threshold included methyl methacrylate (50 ppb), m, p–xylene (41 ppb) and styrene (35 ppb), which methyl methacrylate odor threat value of 2.08 (0.20–2.08) was twice higher than odor threshold, and the pollution sources was plastic plant in industrial park. The characteristics of VOCs showed most abundant species included methanol (8.0–55.4 ppb), isopentane (0.7–66.9 ppb), toluene (2.6–10.1 ppb), acetone (6.0–9.3 ppb) and methyl methacrylate (0.1–8.7 ppb). The result of odor and VOCs concentration showed site I with the highest odor concentration of 40, witch the highest odor threat value of detection species was toluene of 0.21 (concentration of 70.3 ppb). Although odor concentration of the remaining three sampling points (site II–IV) were low, but still were appreciable levels. However, the odor threat value of detection species were very low, showed odor rarely contributed from VOCs.

Fresh ripe, cantaloupes were processed into juice and juice concentrate. Processing trials were conducted on fresh and frozen fruits with and without rind. The effects of maceration enzymes and fining agents on yield and quality were investigated. Compositional measurement included °Brix, pH, titratable acidity, formol values, ascorbic acid content, total carotenoids, sugar and nonvolatile acid profiles, browning indices and Hunter color parameters. Considerable ascorbic acid degradation occurred during processing. The high juice yield (80%) and low acidity suggest its potential use as an alternate sweetener source. Sensory evaluation by a trained panel showed that concentrating the juice samples from flesh and rind can remove the rind aroma and flavor characteristics. Juices obtained from flesh and from flesh and rind were not significantly different (p [less than or equal to] 0.05) except for overall intensity and fresh fruit flavor characters. Single strength juice was significantly different (p [less than or equal to] 0.05) from concentrate on most aroma and flavor characters.
Graduation date: 1991

碩士
嘉南藥理大學
環境工程與科學系
106
This research project is one of the top three projects in the environmental pollution hazard case, because it is an environmental issue that Taiwan people pay more and more attention to and care about air pollution. According to Wang (2017), Odor and Quality in Fishery Feedstuff Manufacturing Plant, the research method is to test the air odor and suspended particles in the operation area of the aquatic feed factory. Comparing the results of this study (2018) and 2017, it shows the improvement of process control equipment and the change of raw materials, helping to improve the air odor in the feed plant area. When the weather conditions at low atmospheric pressure, the odor does not easily spread out of the factory. However, when the wind direction is from northwest to north, the taste of the discharge area will cause odor in the downwind. To explore the feasibility of the oxidation of chlorine dioxide solution to inhibit the air odor of feed mills, spray 50 ppm ClO2 solution as the reaction principle of the simulated scrubber. The results show that the taste of chlorine dioxide can cover odors. However, it is recommended that the gas at different concentrations of odor pollutants be sprayed with a ClO2 solution lower than the odor concentration. The results of the study show that there is a significant reduction in odor concentration due to process equipment improvements and changes in raw materials.

Indiana University-Purdue University Indianapolis (IUPUI)
Taste-and-Odor (T&O) occurrences are a worldwide problem and can locally have extensive socio-economic impacts in contaminated waterbodies. Tracing odorous compounds in surface waters or controlling the growth of producing organisms is particularly challenging. These approaches require the understanding of complex interactions between broad climate heterogeneity, large-scale physical processes such basin hydrology, lake/reservoir circulation, responses of aquatic ecosystems and communities. Eagle Creek Reservoir (ECR), a eutrophic water body, located in central Indiana experiences annual odorous outbreaks of variable durations and intensities that can impair its water quality. Two major compounds, 2-methylisoborneol and geosmin, have been identified as the main culprits occurring seasonally when the reservoir receives high discharges and nutrient loads from its main tributaries. Under these conditions, the growth of T&O-producing bacteria tends to take over other phytoplanktic organisms. Discrete samples collected within the water column during severe outbreaks in 2013 revealed that some bacterioplankton members belonging to Actinobacteria (Streptomyces) and Cyanobacteria (Planktothrix) were involved in the generation of T&O compounds. Most of this production occurred in the upper layers of the water column where higher abundances of key enzymes from MIB and geosmin metabolic pathways were detected. Application of a copper-based algaecide to curb the biosynthesis of bacterial metabolites led to geosmin production (linked to Cyanobacteria) being quickly terminated, whereas MIB levels (linked to Actinobacteria) lingered for several weeks after the algaecide treatment. Significant chemical differences in the association of these metabolites were measured in ECR. Geosmin was dominantly found cell-bound and settling after cellular death increases susceptibility to biodegradation in bottom sediments. MIB was mostly found dissolved making it less susceptible to biodegradation in bottom sediments. Genetic data identified Novosphingobium hassiacum and Sphingomonas oligophenolica (α- Proteobacteria) as potential degraders of geosmin and, four Flavobacterium species (Bacteroidetes) as potential MIB degraders. The role of Eagle Creek natural sediments in the removal of bacterial metabolites via chemical adsorption was also tested but was not proven efficient. Bacterial breakdown activity was demonstrated to be the major loss mechanism of MIB and geosmin.

Cheung Hiu-Ming.
Thesis (M.Phil.)--Chinese University of Hong Kong, 2005.
Includes bibliographical references (leaves 140-150).
Abstracts in English and Chinese.
ABSTRACT --- p.i
ACKNOWLEDGEMENTS --- p.vi
LIST OF FIGURES --- p.xiii
LIST OF TABLES --- p.xv
Chapter CHAPTER 1 --- LITERATURE REVIEW --- p.1
Chapter 1.1 --- Introduction --- p.2
Chapter 1.2 --- Soybeans --- p.3
Chapter 1.2.1 --- Chemistry and nutritional value of soybeans --- p.3
Chapter 1.2.2 --- Protein composition of soybeans --- p.4
Chapter 1.2.3 --- Volatile compounds in soybeans --- p.4
Chapter 1.3 --- Food fermentation --- p.5
Chapter 1.4 --- Chaw tofu --- p.6
Chapter 1.4.1 --- Preparation of tofu --- p.7
Chapter 1.4.2 --- Preparation of chaw tofu --- p.7
Chapter 1.4.3 --- Microorganisms involved in fermentation of chaw tofu --- p.8
Chapter 1.4.4 --- Volatile components in chaw tofu --- p.11
Chapter 1.4.5 --- Proteolytic activity of chaw tofu --- p.12
Chapter 1.5 --- Stinky brine broth --- p.13
Chapter 1.5.1 --- The pH value of stinky brine broth --- p.13
Chapter 1.5.2 --- The salt percentage of stinky brine broth --- p.14
Chapter 1.5.3 --- Volatile components of stinky brine broth --- p.14
Chapter 1.5.4 --- Parameters affecting ammonia production of stinky brine --- p.15
Chapter 1.6 --- Other fermented soy products --- p.16
Chapter 1.6.1 --- Microorganisms involved in the fermentation --- p.16
Chapter 1.6.1.1 --- Fermentation of soybean by bacteria --- p.17
Chapter 1.6.1.1.1 --- Natto --- p.17
Chapter 1.6.1.1.2 --- Kinema --- p.18
Chapter 1.6.1.1.3 --- Soy daddawa --- p.19
Chapter 1.6.1.1.4 --- Hawaijar --- p.20
Chapter 1.6.1.1.5 --- Thua nao --- p.21
Chapter 1.6.1.2 --- Fermentation of soybean by moulds --- p.21
Chapter 1.6.1.2.1 --- Tempe --- p.21
Chapter 1.6.1.2.2 --- Sufu --- p.22
Chapter 1.6.1.2.3 --- Soy sauce --- p.22
Chapter 1.6.1.2.4 --- Soy paste --- p.23
Chapter 1.6.2 --- Formation of volatile compounds during Bacillus fermentation --- p.24
Chapter 1.6.3 --- Biochemical changes during fermentation --- p.21
Chapter 1.7 --- Methods of flavor analysis --- p.30
Chapter 1.7.1 --- Headspace Analysis --- p.31
Chapter 1.7.2 --- Aroma characterization --- p.32
Chapter CHAPTER 2 --- IDENTIFICATION OF ODOROUS COMPOUNDS IN COMMERCIAL CHAW TOFU BASED ON ODOR ACTIVITY EVALUATION --- p.42
Chapter 2.1 --- Introduction --- p.43
Chapter 2.2 --- Materials & Methods --- p.46
Chapter 2.2.1 --- Experimental samples --- p.46
Chapter 2.2.2 --- Headspace-Gas Chromatography-Mass Spectrometry (GC-MS) --- p.46
Chapter 2.2.3 --- Conditions of the Gas Chromatography-Mass Spectrometry (GC-MS) --- p.47
Chapter 2.2.4 --- Compound identifications --- p.48
Chapter 2.2.5 --- Quantification of compounds --- p.48
Chapter 2.2.6 --- Statistical analysis --- p.48
Chapter 2.2.7 --- Calculation of odor activity value (OAV) --- p.49
Chapter 2.3 --- Results & Discussion --- p.50
Chapter 2.3.1 --- Odor activity value (OAV) --- p.51
Chapter 2.3.2 --- Volatile compounds in fresh samples --- p.51
Chapter 2.3.2.1 --- Comparison of odorous compounds in fresh samples among different locations --- p.52
Chapter 2.3.3 --- Volatile compounds in deep-fat fried samples --- p.53
Chapter 2.3.3.1 --- Comparison of odorous compounds in deep-fat fried samples among different locations --- p.54
Chapter 2.3.4 --- Comparison between fresh and deep-fat fried samples --- p.55
Chapter 2.3.5 --- Odorous compounds of chaw tofu based on OAVs --- p.56
Chapter 2.3.6 --- Possible ways for formation of odorous compounds --- p.58
Chapter 2.3.6.1 --- Protein degradation --- p.58
Chapter 2.3.6.2 --- Lipid degradation --- p.59
Chapter 2.3.7 --- Comparison between volatile compounds in chaw tofu and others fermented soybean products --- p.60
Chapter 2.4 --- Conclusion --- p.61
Chapter CHAPTER 3 --- IDENTIFICATION OF ODOROUS COMPOUNDS IN COMMERCIAL CHAW TOFU BASED ON GAS CHROMATOGRAPHY-OLFACTOMETRY --- p.67
Chapter 3.1 --- Introduction --- p.68
Chapter 3.2 --- Materials & Methods --- p.71
Chapter 3.2.1 --- Experimental samples --- p.71
Chapter 3.2.2 --- Gas Chromatography-Mass Spectrometry-Flame Ionization Detection-Olfactometry (GC-MS-FID-O) --- p.71
Chapter 3.2.3 --- Conditions of the Gas Chromatography-Mass Spectrometry --- p.72
Chapter 3.2.4 --- Detection of odor active compounds --- p.73
Chapter 3.2.5 --- Compound identifications --- p.73
Chapter 3.3 --- Results & Discussion --- p.74
Chapter 3.3.1 --- "Fecal, rancid and putrid odor" --- p.74
Chapter 3.3.2 --- "Cabbages, sulfurous and meaty odor" --- p.76
Chapter 3.3.3 --- Green odor --- p.77
Chapter 3.3.4 --- Other odor contributing compounds --- p.77
Chapter 3.3.5 --- Odor generate during deep-fat frying --- p.78
Chapter 3.3.6 --- Comparison between GC-O and OAVs --- p.79
Chapter 3.3.7 --- Comparison between volatile compounds in chaw tofu and others fermented soybean products --- p.80
Chapter 3.4 --- Conclusion --- p.82
Chapter CHAPTER 4 --- EVALUATION OF CHAW TOFU MODEL FERMENTATION BROTH --- p.86
Chapter 4.1 --- Introduction --- p.87
Chapter 4.2 --- Materials & Methods --- p.90
Chapter 4.2.1 --- Model fermentation broth preparation --- p.90
Chapter 4.2.2 --- Tofu sample preparation --- p.91
Chapter 4.2.3 --- Gas Chromatography-Mass Spectrometry --- p.91
Chapter 4.2.3.1 --- Conditions of Gas Chromatography-Mass Spectrometry (GC-MS) --- p.92
Chapter 4.2.3.2 --- Compound identification --- p.93
Chapter 4.2.3.3 --- Quantification of compounds --- p.93
Chapter 4.2.4 --- Viable cell counts --- p.93
Chapter 4.2.5 --- pH value and soluble content --- p.94
Chapter 4.2.6 --- Proteolytic activity --- p.94
Chapter 4.2.7 --- Statistical analysis --- p.95
Chapter 4.3 --- Results & Discussion --- p.96
Chapter 4.3.1 --- Headspaces analysis --- p.96
Chapter 4.3.1.1 --- Changes in volatile composition in model fermentation broths --- p.97
Chapter 4.3.1.2 --- Comparison of volatile compositions between the broths --- p.98
Chapter 4.3.1.3 --- Comparison of volatile compositions among the three deep-fat fried fermented tofu with different broths --- p.101
Chapter 4.3.1.4 --- Comparison of volatile compositions of deep fat fried fermented tofu with that of the commercial chaw tofu --- p.102
Chapter 4.3.2 --- Liquid samples analysis --- p.104
Chapter 4.3.2.1 --- "Changes in viable cell counts, pH values, protease activities and soluble solid contents within model fermentation broths during fermentation" --- p.106
Chapter 4.3.2.2 --- Viable cell counts --- p.107
Chapter 4.3.2.3 --- Soluble solid content --- p.108
Chapter 4.3.2.4 --- Proteolytic activity --- p.106
Chapter 4.3.2.5 --- pH value --- p.110
Chapter 4.4 --- Conclusion --- p.112
Chapter CHAPTER 5 --- GENERAL CONCLUSION --- p.127
APPENDIX --- p.130
IDENTIFICATION OF MICROORGANISMS PRESENTED IN THE MODEL CHAW TOFU FERMENTATION BROTHS BY MICROBIAL IDENTIFICATION SYSTEM (MIDI) --- p.130
Materials & Methods --- p.130
Model fermentation broth preparation --- p.130
Viable cell counts --- p.131
Microbial Identification System (MIDI) --- p.131
Results --- p.133
Suggestion on further investigation --- p.134
REFERNECES --- p.141

Fingerprint profiles generated through GC analysis, are powerful tools for quality control in the food and beverage industry. Beer aroma profiles can be used for the fingerprinting of specific beer brands or for trouble shooting purposes such as the identification of off-flavours. The multichannel silicone rubber trap (MCT) lends itself perfectly to this task. The simplicity and robustness of the MCT makes it ideal for concentrating the volatile compounds that constitute the aroma of an alcoholic beverage such as beer. The retention of these substances by the silicone is based on dissolution into the polymer. This gives more intrinsic stability to the concentrated aroma compounds than traditionally used, adsorption based methods, so transport of the trap and contents should not be a problem. Thermal desorption is used to introduce the trapped aroma compounds to the chromatographic instrument. This eliminates the need for high purity solvents and greatly reduces the sample preparation time. The easily identifiable and stable background peaks from the silicone matrix makes the MCT ideal for repeated use with a thermal desorber. During this study the performance of the MCT as concentration device was investigated for its ability to concentrate aroma volatiles representing a wide range of volatilities. The sampling and desorption procedures were optimised in order to attain the required detection levels and repeatability of the analytical method based on this purge-and-trap sampling scheme
Dissertation (MSc (Chemistry))--University of Pretoria, 2007.
Chemistry
MSc
unrestricted

Mit dem vorliegenden Band „Nach Bologna: Praktika im Studium – Pflicht oder Kür? Empirische Analysen und Empfehlungen für die Hochschulpraxis“ von Wilfried Schubarth, Karsten Speck und Andreas Seidel wird die Reihe „Potsdamer Beiträge zur Lehrevaluation“ unter neuem Titel und veränderter inhaltlicher Schwerpunktsetzung fortgeführt. Die Umbenennung in „Potsdamer Beiträge zur Hochschulforschung“ versteht sich als ein Schritt hin zu einer thematischen Öffnung der Reihe für die verschiedensten Felder der Hochschulforschung. Der vorliegende Band widmet sich einem der zentralen Reformziele von Bologna: der Frage des Praxis- und Berufsbezugs und dabei insbesondere den Praxisphasen im Studium. Mit der Bologna-Reform werden im bildungspolitischen Bereich sehr vielfältige strukturelle und inhaltliche Ziele verfolgt. Das Ziel dieses Bandes besteht deshalb darin, empirische Forschungen zu Praxisbezügen und Praxisphasen im Studium vorzustellen, diese in den Kontext aktueller Debatten um Studienqualität und Studienreform zu stellen sowie Folgerungen für die Gestaltung von Praxisphasen abzuleiten. Inhaltliche Schwerpunkte bilden das BMBF-Forschungsprojekt ProPrax und die Praxisphasen im Lehramtsstudium. Die Beiträge dieses Bandes gehen aus einem gleichnamigen Workshop hervor, der am 1. Oktober 2010 in Potsdam stattfand.
The present conference volume „Beyond Bologna: Internship in studies – obligation or option? Empirical analysis and recommendations on the praxis of higher education“ by Wilfried Schubarth, Karsten Speck and Andreas Seidel is part of the serial “Potsdamer Beiträge zur Lehrevaluation” which is actually renamed as “Potsdamer Beiträge zur Hochschulforschung“. The new title supports modified focal points for research and provides opportunities for several fields of higher education research. The volume focuses on the practical relevance and the development of professional skills in academic studies as one of the central intentions of the Bologna Process. This Reform involves a variety of structural and content-related intentions in the field of educational policy. The aim of this conference volume is therefore to present empirical research with regard to practical relevance and internship in academic studies. It is linked to the current debate concerning quality of academic studies as well as the higher education reform in general and draws conclusions for the practical implementation of academic internships. The ProPrax research project, founded by the BMBF, and its first results as well as internships in teacher education are main issues of this volume. The contributions result from the correspondent Potsdam conference on October 1st 2010.

Die vorliegende Arbeit untersuchte in einem prospektiven Paarvergleich mit cross-over die biochemische Qualität von Erythrozytenkonzentraten, die mittels konventioneller Vollblutspende (VBS) bzw. maschineller Multikomponentenspende (MKS) gewonnen und über einen Zeitraum von 63 Tagen gelagert wurden. Dabei wurde die Überlebensfähigkeit der roten Zellen anhand des ATP-Gehaltes, ihre Sauerstoffabgabefähigkeit mittels des 2,3-DPG-Spiegels sowie die Zellschädigung durch die Bestimmung mehrerer Hämolyseparameter bewertet. Dabei fanden sich, ungeachtet des Herstellungsganges (VBS - MKS), in den ersten drei Wochen nur geringfügige Hinweise auf eine lagerungsbedingte Alteration der Erythrozyten. Nach der dritten Lagerungswoche nahm die Qualität der Erythrozytenkonzentrate aufgrund einer zunehmenden Zellschädigung und Verarmung an Energieträgern ab. Aus den erzielten Resultaten geht hervor, daß keines der beiden Spendeverfahren dem anderen wesentlich überlegen ist, sondern beide Methoden Präparate von hoher Qualität lieferten. Der zweite Teil der Arbeit befaßte sich mit den Auswirkungen der Spende auf die Blut-flußgeschwindigkeit und Blutflußrate in den Fingerkapillaren der Blutspender. Zum Zeitpunkt vor, eine Stunde nach sowie 24 Stunden nach der Spende wurde die Blutflußrate kapillarmikroskopisch mit dem CAM 1 Laser Doppler Anemometer am Fingermittelglied des dritten Fingers der linken Hand bestimmt. Dabei ließen sich keine signifikanten Steigerungen der kapillären Blutflußrate nachweisen
In the present thesis, the biochemical quality of stored erythrocytes, produced by either whole blood donation or by mcs+ cell separator was investigated over a period of 63 days of storage. Therefore, both the survival ratio of the erythrocytes was valued by the content of ATP as well as the reaction of the oxygen dissociation curve messured by the content of 2,3 DPG. Several parameters investigating the ratio of hemolysis were used to describe the extent of the red cell damage during the storage time. The results showed that the whole blood donation as well as the mcs+ cell separator produced packed red cells of high quality. Within the first three weeks of storage the quality of the packed erythrocytes was nearly not influenced by the storing conditions. After this observation period the damage of the red cells was increasing because of the decreasing levels of ATP and 2,3-DPG. In the second part of this thesis the influence of a blood donation on the blood flow velocity in the microcirculation of the donors was investigated. Therefore, the blood flow velocity was measured before the donation as well as one hour or 24 hours respectively after the donation. Measurements were made in the capillaries of the third finger (interphalangeal joint), valued by the CAM 1 laser doppler anemometer. The results showed that despite a blood donation of min. 500 ml an increase of the blood flow velocity could not be found

20 Probanden nahmen im prospektiven Paarvergleich im Abstand von mindestens 8 Wochen im cross-over-Verfahren an je einer Vollblutspende (VBS) und einer maschinellen Multikomponentenspende (MKS) teil. Die erzeugten leukozyten-depletierten Erythrozytenkonzentrate beider Gruppen wurden mittels CPD-50 antikoaguliert und über einen Zeitraum von 63 Tagen in PAGGS-Mannitol gelagert. Beurteilt wurden zum einen rheologische in-vitro-Parameter bei Spendern und Blutkonserven in zweiwöchentlichen Abständen: oszillierende Kapillarviskosimetrie, Erythrozytenaggregometrie und Filtrometrie. Zudem kam bei den Maschinenspendern die neue Methode der Laser-Doppler-Anemometrie zur Ermittlung der kapillären in-vivo-Blutflußgeschwindigkeit in Einzelkapillaren zur Anwendung. Konkordant kam es in beiden Gruppen zum Ansteigen der viskösen Viskosität der Erythrozytenkonzentrate mit überproportionalem Anstieg nach 7 Wochen Lagerung. Die elastische Viskosität stieg ebenfalls in beiden Gruppen an, hier wurden in der Gruppe der Vollblutspender bereits zu Beginn deutlich höhere Werte gemessen, welche in der Vergleichsgruppe erst nach 49 Tagen erreicht wurden. Bei den Blutspendern konnten 24 Stunden nach Spende Veränderungen von visköser und elastischer Viskosität gezeigt werden, welche stark mit Erythrozytenanzahl, Hämoglobin und Hämatokrit korrelierten. Bei konstanten Werten der dynamischen Erythrozytenaggregation zeigte die statische Erythrozytenaggregation bei den Vollblutspenden nach drei Wochen eine Zunahme, in der MKS-Gruppe imponierte ein biphasisches Verhalten mit initialer Abnahme der Lichttransmission. Unabhängig vom Spendeverfahren, trat eine deutliche Abnahme der Filtrierbarkeit der Produkte in beiden Gruppen in den letzten beiden Lagerungswochen auf. Eindrucksvoll war die Reduktion der Filterokklusionsrate auf unter 40 % des Ausgangswertes durch Leukozytenfiltration vor der Lagerung. Bereits 1 Stunde nach der Spende konnten filtrometrische Veränderungen bei den Spendern gezeigt werden, das Signifikanzniveau wurde hier nur knapp verfehlt. Die Bestimmung der kapillären Blutflußgeschwindigkeit zeigte eine Stunde nach Spende eine deutliche Abnahme auf 81 % des Ausgangswertes (p=0,064) in der Gruppe der Maschinenspender. Dies wird als Ausdruck einer diskreten Kreislaufbelastung durch das Aphereseverfahren gewertet
20 test persons took part in the prospective pair-comparison at intervals of at least eight weeks in the cross-over method, consisting of one whole blood donation and one automated cytapheresis. The produced leukocyte-depleted red blood cell concentrates of both groups were anticoagulated via CPD-50 and stored in PAGGS-Mannitol for a period of 63 days. Rheological in-vitro parameters of the donors and the products were evaluated at intervals of two weeks: oscillating capillary viscosimetry, erythrocyte aggregometry and filtrometry. Furthermore the new method of laser-Doppler anemometry was implemented with the cytapheresis group in order to determine the capillary in-vivo blood flow velocity in single-capillaries. In both groups the viscous viscosity of the red blood cell concentrates increased by a disproportionately rise after seven weeks in storage. The elastic viscosity also increased in both groups. Notably higher values were gauged in the cytapheresis group already at the beginning, which were reached by the comparison group only after 49 days. 24 hours after the donation alterations of viscous and elastic viscosity of the donors’ blood could be observed, highly correlating with number of erythrocytes, hemoglobin and hematocrit. With the values of the dynamic erythrocyte aggregation remaining constant the static erythrocyte aggregation of whole blood donors showed an increase after three weeks. Within the automated cytapheresis group a biphasic behaviour with initial decrease of light transmission was noticeable. Independent of the donation method a significant decrease of the products’ filterability could be noted in both groups during the last two weeks in storage. The reduction of the clogging rate to below 40 % of the initial value by means of leukocyte filtration before putting the samples into storage was quite impressive. Filtrometric alterations within the donor groups could be verified only one hour after the donation. The level of significance was not reached here. In the automated cytapheresis group the capillary blood flow velocity showed a significant decrease to 81 % of its initial value (p=0,064) one hour after the donation. This is seen as the expression of a discrete strain on the donor’s circulation caused by the apheresis