16 resultados para Slag Viscosity
em Helda - Digital Repository of University of Helsinki
Resumo:
The number of drug substances in formulation development in the pharmaceutical industry is increasing. Some of these are amorphous drugs and have glass transition below ambient temperature, and thus they are usually difficult to formulate and handle. One reason for this is the reduced viscosity, related to the stickiness of the drug, that makes them complicated to handle in unit operations. Thus, the aim in this thesis was to develop a new processing method for a sticky amorphous model material. Furthermore, model materials were characterised before and after formulation, using several characterisation methods, to understand more precisely the prerequisites for physical stability of amorphous state against crystallisation. The model materials used were monoclinic paracetamol and citric acid anhydrate. Amorphous materials were prepared by melt quenching or by ethanol evaporation methods. The melt blends were found to have slightly higher viscosity than the ethanol evaporated materials. However, melt produced materials crystallised more easily upon consecutive shearing than ethanol evaporated materials. The only material that did not crystallise during shearing was a 50/50 (w/w, %) blend regardless of the preparation method and it was physically stable at least two years in dry conditions. Shearing at varying temperatures was established to measure the physical stability of amorphous materials in processing and storage conditions. The actual physical stability of the blends was better than the pure amorphous materials at ambient temperature. Molecular mobility was not related to the physical stability of the amorphous blends, observed as crystallisation. Molecular mobility of the 50/50 blend derived from a spectral linewidth as a function of temperature using solid state NMR correlated better with the molecular mobility derived from a rheometer than that of differential scanning calorimetry data. Based on the results obtained, the effect of molecular interactions, thermodynamic driving force and miscibility of the blends are discussed as the key factors to stabilise the blends. The stickiness was found to be affected glass transition and viscosity. Ultrasound extrusion and cutting were successfully tested to increase the processability of sticky material. Furthermore, it was found to be possible to process the physically stable 50/50 blend in a supercooled liquid state instead of a glassy state. The method was not found to accelerate the crystallisation. This may open up new possibilities to process amorphous materials that are otherwise impossible to manufacture into solid dosage forms.
Resumo:
This thesis concerns Swedish and Finland-Swedish brochures to families with children, presenting family allowances from the social insurance institutions in the two countries. The aim of the study is to analyse what meanings are conveyed with reference to the conceivable reader and the institution in the brochures. The material consists of information brochures in Swedish from Kela, the social insurance institution of Finland, and Försäkringskassan, the Swedish social insurance agency, issued during 2003–2006. The general theoretical framework is systemic-functional linguistics (SFL) as presented by Halliday & Matthiessen (2004) and Holmberg & Karlsson (2006). The study consists of a quantitative study of the lexical choices of the social insurance brochures. Furthermore, a qualitative process and participant analysis is annotated with the UAM Corpus tool and the results are quantified. Speech functions and modal auxiliaries are analysed qualitatively. The analysis shows that material and relational processes are most common. The relational and verbal processes are used more in the Sweden-Swedish brochures, while the material processes are more common in the Finland-Swedish brochures. The participants in the brochures are the institution, mentioned by its name, and the conceivable reader, directly addressed with “you” (du). In addition, the referent “child” is often mentioned. The participants assigned for the reader are Actor, Receiver, Carrier and Speaker. In the Finland-Swedish texts, the reader is often an Actor, while the reader in the Sweden-Swedish texts is a Carrier. Thus, the conceivable reader is an active participant who takes care of his or her own matters using the internet, communicates actively to the institution and has legal rights and obligations. The institution is visible in the texts but does not have an active role as the name of the institution is mostly used in circumstances. The institution is not often a participant, but when it is, it is Actor, Receiver, Listener and Carrier, expecting the clients to address it. Speech functions are performed in different ways. For instance, questions structure the reading process and commands are realised by modal auxiliaries, not by imperatives. The most common modal auxiliary is kan (can, may), and another common auxiliary is ska (shall, must). Statements are surrounded by subordinate clauses and adverbs that describe situations and criteria. The results of the study suggest that the brochures in the two countries are similar, in particular when produced in similar ways, that is, when the Finland-Swedish texts are not translated. Existing differences reflect the differences in the institutions, the social insurance systems and the cultural contexts. KEYWORDS: Finland-Swedish, Swedish, comparative analysis, SFL, discourse analysis, administrative language, institutional discourse, institutional communication
Resumo:
The thesis studies the translation process for the laws of Finland as they are translated from Finnish into Swedish. The focus is on revision practices, norms and workplace procedures. The translation process studied covers three institutions and four revisions. In three separate studies the translation process is analyzed from the perspective of the translations, the institutions and the actors. The general theoretical framework is Descriptive Translation Studies. For the analysis of revisions made in versions of the Swedish translation of Finnish laws, a model is developed covering five grammatical categories (textual revisions, syntactic revisions, lexical revisions, morphological revisions and content revisions) and four norms (legal adequacy, correct translation, correct language and readability). A separate questionnaire-based study was carried out with translators and revisers at the three institutions. The results show that the number of revisions does not decrease during the translation process, and no division of labour can be seen at the different stages. This is somewhat surprising if the revision process is regarded as one of quality control. Instead, all revisers make revisions on every level of the text. Further, the revisions do not necessarily imply errors in the translations but are often the result of revisers following different norms for legal translation. The informal structure of the institutions and its impact on communication, visibility and workplace practices was studied from the perspective of organization theory. The results show weaknesses in the communicative situation, which affect the co-operation both between institutions and individuals. Individual attitudes towards norms and their relative authority also vary, in the sense that revisers largely prioritize legal adequacy whereas translators give linguistic norms a higher value. Further, multi-professional teamwork in the institutions studied shows a kind of teamwork based on individuals and institutions doing specific tasks with only little contact with others. This shows that the established definitions of teamwork, with people co-working in close contact with each other, cannot directly be applied to the workplace procedures in the translation process studied. Three new concepts are introduced: flerstegsrevidering (multi-stage revision), revideringskedja (revision chain) and normsyn (norm attitude). The study seeks to make a contribution to our knowledge of legal translation, translation processes, institutional translation, revision practices and translation norms for legal translation. Keywords: legal translation, translation of laws, institutional translation, revision, revision practices, norms, teamwork, organizational informal structure, translation process, translation sociology, multilingual.
Resumo:
Six experiments have been conducted to examine digestibility and feeding value of domestic Finnish fibre-rich cereals (barley and oats as compared to maize and wheat) and protein sources (rapeseed meal and cake, peas, faba beans, lupin seeds) for growing turkeys and to investigate effects of age of the birds (from 3 to 12 weeks of age) on digestion process and estimated nutrient digestibility and energy values. Besides, an objective of the study was to test applications of digestibility research methodology for turkeys. Total tract digestibility and apparent metabolizable energy (AME) was assayed in experimental cages using excreta collection, and a slaughter method was applied to sample small intestinal digesta for determination of apparent ileal crude protein digestibility (AICPD), jejuno-duodenal digesta viscosity and caecal volatile fatty acid (VFA) concentration. Digesta viscosity decreased and caecal VFA production increased with age of growing turkeys. Digesta retention times in the small intestine were generally longer in the older birds than in the younger ones. Crude fat digestibility and AME increased with age of growing turkeys, especially with viscous diets. AICPD seemed to decrease with age in most cases. Supplementation with β-gucanase-xylanase decreased viscosity, improved crude fat digestibility and metabolizable energy value and increased VFA production especially in barley-fed turkeys and especially in the young birds. Poor protein digestibility and low energy value of rapeseed meal and rapeseed cake decreased their feeding value for turkeys. In addition, a typical goitrogenic effect of rapeseed feeding was detected. Use of legume seeds as feed for growing turkeys is limited mostly by the low energy value in lupin seeds and the low ileal protein and amino acid digestibility in faba beans. Digestibility of fibre-rich protein sources was not improved with age of the turkeys. Euthanizing the turkeys for AICPD determination by carbon dioxide and bleeding led to lower digestibility values than mechanical stunning and cervical dislocation, suggesting inferiority of carbon dioxide stunning in experimental use. Comparison of AICPD and AME results obtained using different markers showed that considerable differences may occur, especially on total tract level, when acid-insoluble ash gave considerably lower AME values than titanium dioxide and chromic oxide.
Resumo:
The structures of (1→3),(1→4)-β-D-glucans of oat bran, whole-grain oats and barley and processed foods were analysed. Various methods of hydrolysis of β-glucan, the content of insoluble fibre of whole grains of oats and barley and the solution behaviour of oat and barley β-glucans were studied. The isolated soluble β-glucans of oat bran and whole-grain oats and barley were hydrolysed with lichenase, an enzyme specific for (1→3),(1→4)-β-D-β-glucans. The amounts of oligosaccharides produced from bran were analysed with capillary electrophoresis and those from whole-grains with high-performance anion-exchange chromatography with pulse-amperometric detection. The main products were 3-O-β-cellobiosyl-D-glucose and 3-O-β-cellotriosyl-D-glucose, the oligosaccharides which have a degree of polymerisation denoted by DP3 and DP4. Small differences were detected between soluble and insoluble β-glucans and also between β-glucans of oats and barley. These differences can only be seen in the DP3:DP4 ratio which was higher for barley than for oat and also higher for insoluble than for soluble β-glucan. A greater proportion of barley β-glucan remained insoluble than of oat β-glucan. The molar masses of soluble β-glucans of oats and barley were the same as were those of insoluble β-glucans of oats and barley. To analyse the effects of cooking, baking, fermentation and drying, β-glucan was isolated from porridge, bread and fermentate and also from their starting materials. More β-glucan was released after cooking and less after baking. Drying decreased the extractability for bread and fermentate but increased it for porridge. Different hydrolysis methods of β-glucan were compared. Acid hydrolysis and the modified AOAC method gave similar results. The results of hydrolysis with lichenase gave higher recoveries than the other two. The combination of lichenase hydrolysis and high-performance anion-exchange chromatography with pulse-amperometric detection was found best for the analysis of β-glucan content. The content of insoluble fibre was higher for barley than for oats and the amount of β-glucan in the insoluble fibre fraction was higher for oats than for barley. The flow properties of both water and aqueous cuoxam solutions of oat and barley β-glucans were studied. Shear thinning was stronger for the water solutions of oat β-glucan than for barley β-glucan. In aqueous cuoxam shear thinning was not observed at the same concentration as in water but only with high concentration solutions. Then the viscosity of barley β-glucan was slightly higher than that of oat β-glucan. The oscillatory measurements showed that the crossover point of the G´ and G´´ curves was much lower for barley β-glucan than for oat β-glucan indicating a higher tendency towards solid-like behaviour for barley β-glucan than for oat β-glucan.
Resumo:
African indigenous foods have received limited research. Most of these indigenous foods are fermented and they form part of the rich nutritional culture of many groups in African countries. The industrialization and commercialisation of these indigenous African fermented foods should be preceded by a thorough scientific knowledge of their processing which can be vital in the elimination of hunger and poverty. This study highlighted emerging developments and the microbiology of cereal-based and cassava-based food products that constitute a major part of the human diet in most African countries. In addition, investigations were also carried out on the coagulant of the Calotropis procera plant used in traditional production of Nigerian Wara cheese and on the effects of adding a nisin producing Lactococcus lactis strain originating from human milk to Nigerian Wara cheese. Fermented cereal-based food such as ogi utilize popular African and readily available grains maize, millet or sorghum as substrates and is popular as a weaning diet in infants. In this study, the bulkiness caused by starch gelatinization was solved by amylase treatments in the investigation on cooked and fermented oat bran porridge. A similar treatment could reduce the viscosity of any cereal porridge. The properties of the Sodom apple leaves (Calotropis procera) extract in cheesemaking were studied. C. procera was affected by monovalent (K+ and Na+) and divalent (Mg2+ and Ca2+) cations during coagulation. The rennet strength of this coagulant was found to be 7 % compared to animal rennet at 35 °C. Increasing the incubation temperature to 70 °C increased the rennet strength 28-fold. The molecular weight of the partially purified protease was determined by SDS-PAGE and was confirmed by Zymography to be approximately 60 kilodaltons. The high proteolytic activity at 70 °C supported the suitability of the protease enzyme as a coagulant in future commercial production of Nigerian Wara cheese. It was also possible to extend the shelf life of Wara cheese by a nisin producing lactic acid bacteria Lactococcus lactis LAC309. The levels of nisin in both whey and curd fractions of Wara were investigated, results showed a 3 log reduction of toxicogenic Bacillus licheniformis spiked on Wara after 3 days. These studies are the first in Finland to promote the advancement of scientific knowledge in African foods. Recognizing these indigenous food products and an efficient transfer of technology from the developed countries to industrialize them are necessary towards a successful realization of the United Nations Millenium Development Program.
Resumo:
Asymmetrical flow field-flow fractionation (AsFlFFF) was constructed, and its applicability to industrial, biochemical, and pharmaceutical applications was studied. The effect of several parameters, such as pH, ionic strength, temperature and the reactants mixing ratios on the particle sizes, molar masses, and the formation of aggregates of macromolecules was determined by AsFlFFF. In the case of industrial application AsFlFFF proved to be a valuable tool in the characterization of the hydrodynamic particle sizes, molar masses and phase transition behavior of various poly(N-isopropylacrylamide) (PNIPAM) polymers as a function of viscosity and phase transition temperatures. The effect of sodium chloride salt and the molar ratio of cationic and anionic polyelectrolytes on the hydrodynamic particle sizes of poly (methacryloxyethyl trimethylammonium chloride) and poly (ethylene oxide)-block-poly (sodium methacrylate) and their complexes were studied. The particle sizes of PNIPAM polymers, and polyelectrolyte complexes measured by AsFlFFF were in agreement with those obtained by dynamic light scattering. The molar masses of PNIPAM polymers obtained by AsFlFFF and size exclusion chromatography agreed also well. In addition, AsFlFFF proved to be a practical technique in thermo responsive behavior studies of polymers at temperatures up to about 50 oC. The suitability of AsFlFFF for biological, biomedical, and pharmaceutical applications was proved, upon studying the lipid-protein/peptide interactions, and the stability of liposomes at different temperatures. AsFlFFF was applied to the studies on the hydrophobic and electrostatic interactions between cytochrome c (a basic peripheral protein) and anionic lipid, and oleic acid, and sodium dodecyl sulphate surfactant. A miniaturized AsFlFFF constructed in this study was exploited in the elucidation of the effect of copper (II), pH, ionic strength, and vortexing on the particle sizes of low-density lipoproteins.
Resumo:
I de senaste två decennierna har radikalcyklisering, intramolekylär radikaladdition, utvecklats till en viktig syntesmetod för polycykliska indoler och pyrroler. De erhållna produktmolekylerna eller deras derivat är ofta naturliga eller syntetiska alkaloider som väckt biologiskt eller medicinskt intresse. Avhandlingen behandlar både intramolekylära radikaladditioner av pyrrolyl-, indolyl- eller indolylacylradikaler till -bindningar och intramolekylära additioner av flera olika radikaler till indolens eller pyrrolens -system. Också cykliseringar som delreaktioner i radikalkaskader behandlas. Radikalreaktioner kan släckas både oxidativt och reduktivt. För att bibehålla heteroarenens aromaticitet måste cykliseringar till pyrrol- eller indolringen släckas oxidativt. Oxidativa radikaladditioner till aromater benämns homolytiska aromatiska substitutioner. Det finns olika sätt att erhålla en reaktantradikal från en radikalprekursor. I vissa fall har radikalprekursorn en mycket labil bindning som kan brytas fotokemiskt eller med hjälp av en initiator. Till exempel kol-svavelbindningen av en O-etyl-S-alkylxanthat kan brytas på detta sätt. Ofta används dock en radikalmediator för att bilda en reaktantradikal från dess prekursor. Mediatorer är ofta föreningar, som under reaktionsförhållandena själv bildar radikaler med en stor affinitet för en prekursors specifika atom eller atomgrupp vilken abstraheras. Således fungerar mediatorn som mellanhand vid bildning av reaktantradikalen. Exempel på mediatorer av detta slag som använts vid syntes av polycykliska pyrroler och indoler är tributyltennhydrid, hexabutylditenn, tris(trimetylsilyl)silan, tributylgermaniumhydrid, dicumylperoxid, trietylboran, natriumarensulfinater (med ättiksyra) och Se-fenyl-p-toluenselenosulfonat. Också dimetylsulfoxid kan ses som mediator då den bildar metylradikaler vid Fentonreaktion i lösningsmedlet. Övergångsmetallsalter kan även bilda reaktantradikalen från prekursorn genom enelektronoxidationer eller -reduktioner. Vid syntes av polycykliska pyrroler och indoler har reaktantradikalen bildats genom enelektronoxidationer med Mn(OAc)3 eller Ag2+ (Miniscireaktion) och elektronreduktioner med ett Ni(I)-komplex eller SmI2. Avhandlingen är indelad enligt reagenset eller reagensen, som åstadkommer bildning av reaktantradikalen vid syntes av polycykliska indoler och pyrroler. Cirka hälften av avhandlingen behandlar tributyltennhydridmedierade cykliseringar då reagenset trots dess toxicitet är det överlägset mest använda. Avhandlingen diskuterar mekanismen för bildning av reaktantradikalen från prekursorn, cykliseringen och dess möjliga regioselektivitet, andra radikalreaktioner vid radikalkaskader och hur produktradikalen släcks.
Resumo:
Mika KT Pajusen väitös "Towards 'a real reunion'?" – Archbishop Aleksi Lehtonen's efforts for closer relations with the Church of England 1945–1951 on yleiseen kirkkohistoriaan lukeutuva tutkimus Englannin kirkon ja Suomen evankelis-luterilaisen kirkon välisistä suhteista Aleksi Lehtosen arkkipiispakaudella 1945–1951. Suhteita on tutkittu kolmesta näkökulmasta: ekumeenisesta, poliittisesta ja kirkkopoliittisesta. Tutkimuskausi alkaa pastori H.M. Waddamsin joulukuussa 1944 Suomeen tekemän vierailun jälkimainingeista ja päättyy arkkipiispa Lehtosen kuolemaan pääsiäisenä 1951. Kirkollisten suhteiden kehitystä rytmittivät lukuisat vierailut, jotka osoittivat Englannin kirkon asenteen muuttumisen sodan aikaisesta neuvostomyönteisyydestä kylmän sodan aikaiseen täysin vastakkaiseen kantaan. Englantilaiset vieraat kohtasivat Suomessa sekä kirkon että yhteiskunnan ylimmän johdon. Molemmat maat olivat valmiita tukemaan hyviä kirkollisia suhteita tilanteen niin salliessa, joskaan eivät kovin suunnitelmallisesti. Suomen evankelis-luterilainen kirkko käytti hyviä suhteita Englannin kirkkoon saadakseen tukea ja ymmärrystä omalle kirkolleen ja yhteiskunnalleen kokemaansa Neuvostoliiton uhkaa vastaan erityisesti vaaran vuosina 1944–1948. Englannin kirkko halusi tukea suomalaista sisarkirkkoaan, mutta varoi, ettei tuottaisi tuellaan enemmän haittaa kuin hyötyä suhteessa Neuvostoliittoon. Sodan jälkeinen ekumeeninen jälleenrakentaminen lähensi kirkkoja toisiinsa. Lehtonen pyrki jatkamaan 1930-luvun kirkkojen välisiä, ehtoollisvieraanvaraisuuden saavuttaneita neuvotteluita kohti täyttä kirkollista yhteyttä. Häntä motivoi sekä evankelis-katolinen teologia että pyrkimys tukea oman maan ja kirkon läntisiä yhteyksiä. Tämä haastoi Englannin kirkon ekumeenisen linjan, joka Suomen kirkon sijasta pyrki jatkamaan neuvotteluja Tanskan, Norjan ja Islannin luterilaisten kirkkojen kanssa, joilla ei vielä ollut virallista ekumeenista sopimusta Englannin kirkon kanssa. Lehtosen pyrkimyksistä huolimatta Englannin kirkko päätyi jättämään Suomen tilanteen hautumaan. Sillä se tarkoitti suhteiden koetinkivenä olleen historiallisen piispuuden leviämistä läpi Suomen kirkon ennen kuin katsoi olevansa valmis jatkamaan kohti täyttä kirkollista yhteyttä. Molemmissa kirkoissa vaikutti pieni, innokkaiden, lähempiä suhteita toivoneiden kirkollisten vaikuttajien ydinjoukko. Englantilaisia Suomen-ystäviä motivoi tarve auttaa Suomea hankalassa poliittisessa tilanteessa. Suomessa arkkipiispa Lehtonen tuki korkeakirkollista liturgista liikettä, jolla oli läheinen yhteys anglikaanisuuteen, mutta joka sai vastaansa vanhoilliset pietistit. Suomen kirkon yleinen mielipide asettui etupäässä pietistiselle kannalle, jolle anglikaanisuus näyttäytyi teologisesti sekä liian katolisena että liian reformoituna. Kirkolliset suhteet tasaantuivat vuoden 1948 Lambeth-konferenssin jälkeen, joka rohkaisi anglikaanisia kirkkoja hyväksymään 1930-luvun neuvottelujen lähempiin kirkollisiin suhteisiin tähtäävät suositukset. Lehtonen näytti tyytyvän tähän. Samaan aikaan lähempää kirkollista kanssakäymistä tukenut ekumeeninen jälleenrakennus tuli tiensä päähän. Lehtonen jatkoi läheisempien suhteiden edistämistä, mutta hänen intonsa hiipui yhdessä heikkenevän terveydentilan kanssa. Osoituksena Lehtosen linjan kapeudesta Suomen evankelis-luterilaisen kirkon piispoista ei löytynyt hänen kuoltuaan ketään, joka olisi jatkanut hänen aktiivista anglikaanimyönteistä linjaansa.
Resumo:
Lullabies in Kvevlax. Linguistic structures and constructions. The study is a linguistic analysis of constructions that shape the texts used in lullabies in Kvevlax in Ostrobothnia in Finland. The empirical goal is to identify linguistic constructions in traditional lullabies that make use of the dialect of the region. The theoretical goal was to test the usability of Construction Grammar (CxG) in analyses of this type of material, and to further develop the formal description of Construction Grammar in such a way as to make it possible to analyze all kinds of linguistically complex texts. The material that I collected in the 1960s comprises approximately 600 lullabies and concomitant interviews with the singers on the use of lullabies. In 1991 I collected additional material in Kvevlax. The number of informants is close to 250. Supplementary material covering the Swedish-language regions in Finland was compiled from the archives of the Society of Swedish Literature in Finland. The first part of the study is mainly based on traditional grammar and gives general information about the language and the structures used in the lullabies. In the detailed study of the Kvevlax lullabies in the latter part of the study I use a version of Construction Grammar intended for the linguistic analysis of usage-based texts. The analysis focuses on the most salient constructions in the lullabies. The study shows that Construction Grammar as a method has more general applicability than traditional linguistic methods. The study identifies important constructions, including elements typical of this genre, that structure the text in different variants of the same lullabies. In addition, CxG made it possible to study pragmatic aspects of the interactional, cultural and contextual language that is used in communication with small children. The constructions found in lullabies are also used in language in general. In addition to being able to give detailed linguistic descriptions of the texts, Construction Grammar can also explain the multidimensionality of language and the variations in the texts. The use of CxG made it possible to show that variations are not random but follow prototypical linguistic patterns, constructions. Constructions are thus found to be linguistic resources with built-in variation potentials.
Resumo:
Tutkimuksen kirjallisuuskatsauksessa keskityttiin jäätelöpuikkoihin, erilaisiin suklaakuorrutteisiin ja elintarvikkeiden kuorruttamiseen suklaalla. Lisäksi kirjallisuuskatsauksessa perehdyttiin suklaan koostumukseen, nestemäisen suklaan virtausominaisuuksiin ja koostumuksen ja virtausominaisuuksien välisiin vuorovaikutuksiin. Kokeellisessa osassa tavoitteena oli selvittää, miten maitosuklaakuorrutteen rasvapitoisuuden, emulgointiainepitoisuuden ja kuorrutteen lämpötilanvaihtelut vaikuttavat kuorrutteen viskositeettiin, myötöjännitykseen, jähmettymisaikaan ja jäätelöpuikon päälle jäävän kuorrutteen määrään. Erityisesti pyrittiin selvittämään, miten jäätelöpuikon päälle jäävän kuorrutteen määrää saadaan säädeltyä kuorrutteen rasvapitoisuutta, emulgointiainepitoisuutta ja lämpötilaa muuttamalla. Tutkimuksen koeasetelma tehtiin Box-Behnken-mallilla. Selittäviksi muuttujiksi tutkimukseen valittiin kuorrutteen rasvan määrä, emulgointiaineen määrä ja kuorrutteen lämpötila jäätelöpuikkoja kuorrutettaessa. Vastemuuttujina oli kuorrutteen jähmettymisaika, viskositeetti, myötöjännitys ja jäätelöpuikon päälle jäävän kuorrutteen määrä. Tulokset käsiteltiin regressioanalyysin avulla. Muuttujien välisiä vuorovaikutuksia tutkittiin vastepintamallilla. Vastemuuttujien välisiä korrelaatioita tutkittaessa käytettiin Pearsonin korrelaatiokerrointa. Kuorrutteen rasvan määrän lisääntyminen vähensi tilastollisesti merkitsevästi jäätelöpuikon päälle jäävän kuorrutteen määrää, kuorrutteen jähmettymisaikaa, viskositeettia ja myötöjännitystä. Emulgointiaineen määrän lisääminen kuorrutteessa pienensi kuorrutteen määrää jäätelöpuikon päällä, kuorrutteen jähmettymisaikaa ja kuorrutteen myötöjännitystä. Kuorrutteen lämpötilan lisääminen jäätelöpuikkoja kuorrutettaessa pienensi kuorrutteen määrää ja viskositeettia. Kuorrutteen jähmettymisaika sen sijaan piteni lämpötilaa lisättäessä. Tutkimuksen perusteella voidaan sanoa, että jäätelöpuikkoja kastettaessa suklaakuorrutteen lämpötila, rasvan määrä ja lesitiinin määrä vaikuttivat jäätelöpuikon päälle jäävän kuorrutteen määrään. Vastepintamallinnuksen käyttö soveltui hyvin suklaakuorrutteen määrän tutkimiseen. Sen avulla saatiin selvitettyä, miten jäätelöpuikon päälle jäävän kuorrutteen määrää saadaan säädeltyä muuttamalla kuorrutteen emulgointiainepitoisuutta, rasvapitoisuutta ja lämpötilaa.
Resumo:
Cereal water-soluble β-glucan [(1→3)(1→4)-β-D-glucan] has well-evidenced health benefits and it contributes to the texture properties of foods. These functions are characteristically dependent on the excellent viscosity forming ability of this cell wall polysaccharide. The viscosity is affected by the molar mass, solubility and conformation of β-glucan molecule, which are further known to be altered during food processing. This study focused on demonstrating the degradation of β-glucan in water solutions following the addition of ascorbic acid, during heat treatments or high pressure homogenisation. Furthermore, the motivation of this study was in the non-enzymatic degradation mechanisms, particularly in oxidative cleavage via hydroxyl radicals. The addition of ascorbic acid at food-related concentrations (2-50 mM), autoclaving (120°C) treatments, and high pressure homogenisation (300-1000 bar) considerably cleaved the β-glucan chains, determined as a steep decrease in the viscosity of β-glucan solutions and decrease in the molar mass of β-glucan. The cleavage was more intense in a solution of native β-glucan with co-extracted compounds than in a solution of highly purified β-glucan. Despite the clear and immediate process-related degradation, β-glucan was less sensitive to these treatments compared to other water-soluble polysaccharides previously reported in the literature. In particular, the highly purified β-glucan was relatively resistant to the autoclaving treatments without the addition of ferrous ions. The formation of highly oxidative free radicals was detected at the elevated temperatures, and the formation was considerably accelerated by added ferrous ions. Also ascorbic acid pronounced the formation of these oxidative radicals, and oxygen was simultaneously consumed by ascorbic acid addition and by heating the β-glucan solutions. These results demonstrated the occurrence of oxidative reactions, most likely the metal catalysed Fenton-like reactions, in the β-glucan solutions during these processes. Furthermore, oxidized functional groups (carbonyls) were formed along the β-glucan chain by the treatments, including high pressure homogenisation, evidencing the oxidation of β-glucan by these treatments. The degradative forces acting on the particles in the high pressure homogenisation are generally considered to be the mechanical shear, but as shown here, carbohydrates are also easily degraded during the process, and oxidation may have a role in the modification of polysaccharides by this technique. In the present study, oat β-glucan was demonstrated to be susceptible to degradation during aqueous processing by non-enzymatic degradation mechanisms. Oxidation was for the first time shown to be a highly relevant degradation mechanism of β-glucan in food processing.
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Tutkielman kirjallisuuskatsauksessa tarkasteltiin kauran leivontateknologisia ominaisuuksia, entsyymiaktiivista leivontaa ja ruismaltaan hyödyntämistä vähägluteenisessa leivonnassa. Kokeellisessa osiossa tutkittiin ruismallashapantaikinasta valmistetun uutteen vaikutusta kaurataikinan viskositeettiin ja kauraleivän ominaisuuksiin. Työn tarkoituksena oli kehittää maultaan ja rakenteeltaan onnistunut rukiinmakuinen kauraleipä. Ruismaltaan entsyymien annettiin pilkkoa keliaakikolle haitallisia rukiin prolamiineja hapantaikinaprosessissa. Hapantaikinasta erotettiin uute sentrifugoimalla. Leivontakokeisiin käytettiin entsyymiaktiivista ja kuumentamalla inaktivoitua uutetta. Uutteella korvattiin taikinavettä 15, 25 ja 30 % (taikinan painosta). Leivonta toteutettiin miniatyyrikoossa, vuokaleivontana 20 g:n taikinapaloja käyttäen. Taikinoiden viskositeetti mitattiin tarkoituksena seurata beetaglukaanin hydrolyysiä. Rukiin makua mitattiin koulutetun raadin avulla. Happaman uutteen lisäys laski taikinan pH-arvoa noin 5,8:sta noin 4,4:ään. Entsyymiaktiivisen uutteen lisäys laski taikinan viskositeettia ja inaktivoitu uute puolestaan kasvatti sitä. Leipien sisus tiivistyi, jolloin mitatut sisuksen kovuudet kasvoivat uutteen lisäyksen myötä. Uutelisäys paransi leipien makua ja aromia. Uutteen vaikutuksesta leipien huokoset olivat pienempiä ja ne jakaantuivat tasaisemmin leipämatriisiin. Jos uutetta käytettiin inaktivoituna, leipien murenevuus kasvoi. Tutkimuksessa kehitetyn teknologian avulla oli mahdollista valmistaa hyvänlaatuinen, rukiinmakuinen kauraleipä myös ilman että uutteen entsyymit inaktivoitiin keittämällä. Tähän vaikutti ilmeisesti taikinan alhainen pH, joka inhiboi alfa-amylaasia, ja kauratärkkelyksen korkea liisteröitymislämpötila, jolloin entsyymien inaktivoituminen paiston aikana tapahtui ennen kuin tärkkelys tuli alttiiksi liialliselle pilkkoutumiselle. Tämä mahdollistaa uutteen käytön osana leivontaprosessia ilman inaktivointia. Hapantaikinafermentaatio osana gluteenitonta leivontaa havaittiin toimivaksi yhdistelmäksi, sillä se paransi leivän väriä, makua ja rakennetta. Myös leivän homeeton aika parani jo vähäisenkin uutelisäyksen vaikutuksesta. Näyttää siltä, että tämän teknologian avulla on mahdollista tuoda esille pitkään kaivattua rukiin makua vähägluteenisten kauraleipien valikoimassa. Laskennallisesti ja aiempiin tuloksiin tukeutuen, voitiin päätellä, että leivän prolamiinipitoisuudessa on mahdollista päästä tasolle 63,5 mg/kg, mutta jatkokehityksen avulla päästäisiin luultavasti vielä parempiin tuloksiin.
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Syftet med studien är att undersöka sydfinlandssvenska högskolestuderandes kännedom om och inställning till ett urval finlandssvenska ord och uttryck samt till dessa ords allmänsvenska motsvarigheter. För att undersöka detta har jag gjort en enkätundersökning bland svenskspråkiga högskolestuderande i Helsingfors. Jag undersöker i vilken utsträckning informanterna använder finlandssvenska ord och uttryck och i vilken utsträckning allmänsvenska. Jag undersöker även vilka finlandssvenska ord och uttryck de använder mest och vilka minst, samt vilka allmänsvenska ord och uttryck de använder mest och vilka minst. Dessutom undersöker jag om informanternas språkliga bakgrund har ett samband med deras kännedom om och användning av finlandssvenska respektive allmänsvenska ord och uttryck. Avsikten med den här undersökningen är att öka kunskapen om hur unga finlandssvenskar förhåller sig till sin finlandssvenska varietet samt till den allmänsvenska varieteten som de i vuxen ålder förutsätts behärska åtminstone i någon mån. Idén till enkätundersökningen kommer från Margareta Södergårds och Sofie Tjärus studie Blivande barnträdgårdslärares syn på finlandismer (2008). Urvalet finlandismer kommer från en mindre undersökning Goda och onda finlandismer som Mikael Reuter (2004) har gjort bland en grupp finlandssvenska och sverigesvenska språkvårdare. Sammanlagt ingår 55 finlandismer av olika slag i enkäten. För varje finlandism finns det även en eller fler allmänsvenska motsvarigheter och sammanlagt ingår därför 122 ord och uttryck i enkäten. Mina informanter är 162 studerande vid två svenska högskolor i Helsingfors. För att få reda på relevanta bakgrundsfakta om informanterna har jag använt samma formulär som Therese Leinonen i Svenskan i Finland ett språk i kläm? (Leinonen & Tandefelt 2000). Jag har utgående från informanternas generella språkanvändning delat in dem i tre grupper. En grupp vars vardag är finskdominerad, en vars vardag är svenskdominerad och en vars vardag utspelar sig till ungefär lika stor del på svenska som på finska. Undersökningen är kvantitativ och för att behandla materialet har statistikprogrammet SPSS använts. Studien visar att informanterna förhåller sig rätt lika till finlandismerna och de allmänsvenska orden och uttrycken. De känner ungefär lika bra till de finlandssvenska och de allmänsvenska orden och uttrycken, men de prefererar ändå i viss mån finlandismerna framför de allmänsvenska orden och uttrycken. Mina informanter förefaller i viss mån vara mer accepterande mot finskpåverkade finlandismer än vad Reuters (2004) informanter är, och de förhåller sig mindre positiva till metaforiska uttryck än vad Reuters informanter gör. Informanter med en svenskspråkig vardag verkar använda allmänsvenska ord och uttryck i högre utsträckning än vad informanterna med en finskspråkig vardag gör. Resultaten tyder dessutom på att informanterna med en svenskspråkig vardag också känner till fler allmänsvenska ord och uttryck även om de inte alltid själva är beredda att använda dem. Studien visar även att informanter med en svenskspråkig vardag använder en del metaforiska uttryck mer än vad informanterna med en finskspråkig vardag gör. Det är överlag tydligt att undersökningens informanter, finlandssvenska högskolestuderande från södra Finland, varken har en speciellt stor kännedom om metaforiska uttryck eller en speciellt positiv inställning till dessa. Bristande behärskning av metaforiska uttryck, idiom och kollokationer kan ses som ett första steg mot språkförlust och sett ur den synvinkeln är resultatet oroväckande. Det stärker den rådande uppfattningen att allt inte står helt rätt till med den svenska språkbehärskningen bland unga finlandssvenskar.
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Cereal arabinoxylans, guar galactomannans, and dextrans produced by lactic acid bacteria(LAB) are a structurally diverse group of branched polysaccharides with nutritional and industrial functions. In this thesis, the effect of the chemical structure on the dilute solution properties of these polysaccharides was investigated using size-exclusion chromatography(SEC) and asymmetric flow field-flow fractionation (AsFlFFF) with multiple-detection. The chemical structures of arabinoxylans were determined, whereas galactomannan and dextran structures were studied in previous investigations. Characterization of arabinoxylans revealed differences in the chemical structures of cereal arabinoxylans. Although arabinoxylans from wheat, rye, and barley fiber contained similar amounts of arabinose side units, the substitution pattern of arabinoxylans from different cereals varied. Arabinoxylans from barley husks and commercial low-viscosity wheat arabinoxylan contained a lower number of arabinose side units. Structurally different dextrans were obtained from different LAB. The structural effects on the solution properties could be studied in detail by modifying pure wheat and rye arabinoxylans and guar galactomannan with specific enzymes. The solution characterization of arabinoxylans, enzymatically modified galactomannans, and dextrans revealed the presence of aggregates in aqueous polysaccharide solutions. In the case of arabinoxylans and dextrans, the comparison of molar mass data from aqueous and organic SEC analyses was essential in confirming aggregation, which could not be observed only from the peak or molar mass distribution shapes obtained with aqueous SEC. The AsFlFFF analyses gave further evidence of aggregation. Comparison of molar mass and intrinsic viscosity data of unmodified and partially debranched guar galactomannan, on the other hand, revealed the aggregation of native galactomannan. The arabinoxylan and galactomannan samples with low or enzymatically extensively decreased side unit content behaved similarly in aqueous solution: lower molar mass samples stayed in solution but formed large aggregates, whereas the water solubility of the higher-molar-mass samples decreased significantly. Due to the restricted solubility of galactomannans in organic solvents, only aqueous galactomannan solutions were studied. The SEC and AsFlFFF results differed for the wheat arabinoxylan and dextran samples. Column matrix effects and possible differences in the separation parameters are discussed, and a problem related to the non-established relationship between the separation parameters of the two separation techniques is highlighted. This thesis shows that complementary approaches in the solution characterization of chemically heterogeneous polysaccharides are needed to comprehensively investigate macromolecular behavior in solution. These results may also be valuable when characterizing other branched polysaccharides.