Browsing by Subject "rakenne"
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(2021)Tutkimuksen tarkoituksena oli kartoittaa optimaalinen hydrokolloidiyhdistelmä, joka parantaa gluteenittoman leivän rakennetta ja tuoreena säilymistä. Hypoteesina oli, että löytyisi tietty kahden hydrokolloidin yhdistelmä koesuunnitelmaa käyttämällä. Tutkimuksessa käytettiin kolmea eri hydrokolloidia ja niiden määrät vaihtelivat kolmella eri tasolla. Hydrokolloidien vesiliuosten reologisia ominaisuuksia tutkittiin viskositeetti- ja oskillaatiomittauksilla. Leivistä mitattiin tilavuus, rakenne ja rakenteen säilyminen seitsemän vuorokauden säilytyksessä ja raskista mitattiin pH ja happoluku. Leivistä tehtiin myös aistinvarainen asiantuntija-arviointi. Raskien pH-arvojen keskiarvo oli 4,49 ±0,01 ja happoluvun keskiarvo 12,9 ±0,2. Hydrokolloidien vesiliuosseosten, GM + MNS1 ja GM + MNS2, viskositeettien mittauksissa virtauskäyrissä ei ollut eroa mutta GM:n (galaktomannaanista muodostunut kasvikumi, joka on peräisin palkokasvista) viskositeetti oli selvästi matalampi kuin seosten. Oskillaatiomittauksessa GM:n huomattiin myös erottuvan seoksista huomattavan paljon pienemmällä viskositeetilla sekä varasto- ja häviömoduulilla. GM muodostaa yksin ollessaan heikon geelirakenteen, mutta seoksilla on vahvempi geelirakenne. Modde-ohjelmiston vastepintaohjelman avulla saaduista tuloksista voitiin nähdä vain kimmoisuuden ja joustavuuden mallintuvan yhden päivän säilytyksen jälkeen. Tehtyjen analyysien perusteella päivä leivonnan jälkeen modifioitu neutraali selluloosa 1 (MNS1) ja modifioitu neutraali selluloosa 2 (MNS2) paransivat leivän joustavuutta. MNS2 lisäsi myös leipien kimmoisuutta, kun taas MNS1:llä ei ollut vaikutusta ja GM pienensi leipien kimmoisuutta. Myös seitsemännen säilytyspäivän jälkeen MNS1 piti leivän rakennetta joustavampana muihin saman ikäisiin leipiin verrattuna. Käytetyillä hydrokolloideilla ei ollut tilastollista eroa leivän kovuudessa, pureskeltavuudessa eikä murtumisherkkyydessä. Selkeitä eroja leivissä näkyi aistinvaraisesti arvioituna vain huokosjakaumassa. Huokosjakaumalta epätasaisimpia olivat leivät, joissa oli käytetty MNS1 tai MNS2 tasolla 3. Leipien säilönnän aikana oli kuitenkin huomattavissa selkeää kuivumista ja kovettumista. Leivonnasta seitsemännen päivän kohdalla lähes kaikki leivät olivat todella kovia ja sisus oli kuiva. Leipien maku oli myös heikentynyt aiempiin päiviin verrattuna. Tutkittujen hydrokolloidien vaikutusta leivän pehmeyteen ja nautittavuuteen ei voida todentaa tehtyjen tutkimusten perusteella, aistinvaraisesti arvioituna leivät eivät olleet selkeästi pehmeämpiä hydrokolloidilisäysten myötä.
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(2015)The purpose of this study was to investigate the structure of ice cream, especially the effects of temperature, sugar composition and stabilizer-emulsifier concentration on the melt down, hardness and moulding properties of ice cream. The aim was to produce a soft and easily mouldable ice cream that suits the intended purpose. A sensory evaluation was conducted to the ice creams with desired structural properties. The literature review deals with ice cream ingredients, manufacturing process and factors affecting ice cream structure. For the experimental study, 16 ice creams with different compositions were made. The ice creams contained 12 or 6 % fat, different types of sugar compositions (A, B, C, D, E, F) and different concentrations of two types of stabilizer and emulsifier blends (A, B). Ice creams were stored at different temperatures. The hardness of ice cream was measured with a Texture Analyser, the melting rate was determined and the moulding properties were analysed with a moulding test. The two ice creams with desired structure were compared to a commercial ice cream in a sensory evaluation. The results of the hardness measurements revealed, that temperature and sugar composition affected hardness the most. Stabilizer and emulsifier concentration and type did not have an effect. The softest ice creams were those stored at higher temperatures and those made with sugar composition C, D, E and F. The slowest melting ice creams were the ones containing greater amounts of stabilizers and emulsifiers. The ice cream made with sugar composition D melted the fastest. For the moulding test, the softer ice creams were the easiest to mould. The ice cream made with sugar composition D was found to be too soft, almost runny, and the ones made with sugar composition A and B were found to be too hard. The ice creams made with sugar composition C, E and F were found pleasing. The batches containing a greater amount of stabilizer and emulsifier were found to be a bit gummy. In the sensory evaluation there were only one difference in sweetness found between the study ice creams and the commercial one. There were no differences found in creaminess and over all liking. From this can be concluded that the study ice creams are accepted by the consumers as well.
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(2014)Thesis literature review deals with composition of cow´s milk, yogurt manufacturing, composition and process attributes affecting textural properties of yogurt and measuring textural properties of yogurt. Plain, stirred yogurts (kg) were manufactured at Valio Riihimäki and Oulu Dairies. The aim of the research was to find out attributes that affect yogurt quality. First milk base composition was determined and, yogurt textural properties were determined (viscosity, graininess, syneresis) using different techniques. Finally yogurt statistical relationships or Pearson correlations and statistical significance between yogurt textural properties and milk base composition and manufacturing process were determined. Additional objective was to determine common specification limits to yogurt textural properties. Statistical analysis; pearson correlation coefficients, p-value and specification limits were carried out using MINITAB®16 statistical software. Good yogurt texture is viscous, free from grains and syneresis. This study showed that yogurt textural properties (viscosity, graininess and syneresis) were affected significantly by yogurt manufacturing plant. There were a lot of fluctuations in yogurt textural properties. Consequently yogurt viscosity fluctuated over 50%, graininess approx. 25% and syneresis approx. 30%. According to this study, yogurts standing a long time before packaging, were less viscose or watery compared to those with shorter standing time prior to packaging. Graininess and evaporating process were found to correlate positively. Yogurts were with more grains when manufacturing process`s evaporating temperature and evaporating rate (l/h) were higher. The higher milk base fat and dry matter content (%) were found to correlate lesser whey separation in yogurt. In addition the higher evaporating rate was in the yogurt manufacturing process, the lesser whey separation was observed. Results from this research are useful for developing dairy processes concerning yogurt manufacturing.
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(2023)Uusien proteiinituotteiden kehittäminen on nostanut märkäekstruusion kiinnostavaksi tutkimuskohteeksi. Märkäekstruusiolla voidaan valmistaa liha-analogeja, joissa on lihaproteiineja muistuttavia kuitumaisia rakenteita. Viime vuosina märkäekstruusiotutkimukset ovat keskittyneet yhdistämään kahta tai useampaa erilaista proteiinia ja muodostamaan niistä hybridiekstrudaatin. Yleisesti käytettyjä raaka-aineita ekstruusiossa ovat eri kasviproteiinit, mutta muistakin proteiineista on muodostettu toimivia hybridiekstrudaatteja, kuten maito- ja lihaproteiineista. Tämän tutkielman tavoitteena oli selvittää erilaisten maito- ja perunaproteiiniseosten ja prosessiolosuhteiden vaikutusta kuitumaisen rakenteen muodostumiseen märkäekstruusiossa. Maito- ja perunaproteiinien märkäekstruusiosta on olemassa vain muutamia tutkimuksia, minkä vuoksi aihe on erittäin ajankohtainen tutkittavaksi. Tutkielman hypoteesina oli, että kaurakuitukonsentraatista ja hera- ja perunaproteiinista onnistutaan muodostamaan kuitumaisia rakenteita märkäekstruusiolla. Ekstruusiossa käytettiin kaksiruuvista ekstruuderia, johon liitettiin pitkä jäähdyttävä suutin. Jauheseoksissa kaurakuitukonsentraatin osuus oli vakio (50 %) ja hera- ja perunaproteiinin osuus vaihtelivat. Tutkielman koeasetelmana oli Split-plot-Box-Behnken-koeasetelma, jossa muuttujina olivat heraproteiini-isolaatin osuus jauheseoksessa (25/37,5/50 %), syötetyn massan vesipitoisuus (57,5/60/62,5 %) ja pitkän jäähdytyssuuttimen lämpötila (40/60/80 ℃). Vastemuuttujina olivat paine suuttimella ja vääntömomentti, ja ekstrudaatin rakenneominaisuudet (kovuus, kumimaisuus, kimmoisuus, pureskeltavuus), poikittainen ja pitkittäinen leikkauslujuus, väriparametrit (L*, a* ja b*) ja vedenabsorptiokyky. Tulosten analysointiin käytettiin ML- ja PLSregressioanalyysejä. Hera- ja perunaproteiinista onnistuttiin muodostamaan hybridiekstrudaatti kaikilla käytetyillä prosessiparametrien arvoilla. Lisäksi osaan näytteistä muodostui kuitumainen rakenne. Matala massan vesipitoisuus nosti ekstrudaatin kovuutta, kumimaisuutta, kimmoisuutta, pureskeltavuutta, vääntömomenttia ja painetta suuttimella. Matala jäähdyttävän suuttimen lämpötila suurensi ekstrudaatin kumimaisuutta, pureskeltavuutta, leikkauslujuuksia, vääntömomenttia ja painetta suuttimella. Ekstrudaatin vedenabsorptiokyky suureni, kun heraproteiinin osuus, massan vesipitoisuuden ja jäähdyttävän suuttimen lämpötila kasvoivat. Matala massan vesipitoisuus ja suuttimen lämpötila kasvattivat pitkittäisiä leikkauslujuuksia. Heraproteiinin osuutta nostamalla pitkittäiset leikkauslujuudet suurenivat. Heraproteiinin lisäys vaalensi ekstrudaatteja aiheuttaen niihin keltaisuutta. Tutkielman tulokset tukevat hypoteesia, jonka mukaan hera- ja perunaproteiinista voidaan muodostaa toimiva hybridiekstrudaatti märkäekstruusiolla. Lisäksi ne ovat potentiaalisia raaka-aineita muodostamaan kuitumaisia rakenteita. Jatkossa tarvittaisiin tutkimusta hybridiekstrudaattien aistinvaraisista ominaisuuksista.
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(2014)The literature review was concerned with colourful vegetables and the most common pigments in vegetables: carotenoids, anthocyanins, betalaines and chlorophyll. In addition, how thermal treatments affect these pigments and the structure of vegetable was reviewed. The aim of the experimental work was to investigate the effect of thermal treatments on the colour, pigments and texture of carrots and beet-roots. Seven coloured carrot cultivars and four coloured beet-root cultivars were examined. Three different kinds of thermal treatments were applied to the samples: blanching, boiling and steaming. Orange and purple carrots contained the highest amounts of carotenoids. The total carotenoid content of the carrots increased due to the thermal treatments. Purple carrots were the only carrots which contained anthocyanins. Anthocyanin stability is pH dependent: boiling in slightly acidic water had a minor impact on anthocyanin content than boiling in pure water. Red beet was the most betalain-rich beet-root. Other cultivars contained remarkably less betalaines. Betalain content decreased due to the thermal treatments. Betalain degradation due to the thermal treatments was detected as the pigment content and colour changed. Thermal treatments softened the vegetable structure. Thermal treatment improves the extraction of the pigments from the vegetable structure, which was detected as the increase in pigment concentration, leading to an enhancement of bioavailability of pigments. However, long thermal treatments cause pigment degradation and reduce the nutritional value of the vegetables.
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(2015)Maisterintutkielman kirjallisuusosassa perehdyttiin tuorejuustoihin ja niiden valmistusmenetelmiin. Tässä tutkielmassa tutkittiin pääasiassa leikattavan tuorejuuston kolmea eri valmistusmenetelmää: säkitys-, ultrasuodatus- ja rahka-rasvaseosmenetelmää. Kirjallisuusosassa käsiteltiin lisäksi tuorejuustojen koostumusta, valmistusmenetelmien kannattavuutta, kuten tuorejuustosaantoa ja laatuominaisuuksia. Kokeellisessa osassa valmistettiin leikattavaa tuorejuustoa pilot-mittakaavassa ultrasuodatus- ja rahka-rasvaseosmenetelmällä ja verrattiin teollisesti säkitysmenetelmällä valmistettuun leikattavaan tuorejuustoon. Näytteistä tutkittiin valmistusmenetelmien vaikutuksia leikattavan tuorejuuston valmistusprosessiin, laatuun, rakenteeseen, aistinvaraisiin ominaisuuksiin, säilyvyyteen ja kannattavuuteen. Tuorejuustojen aistittavaa laatua tutkittiin perinteisen miellyttävyystestin avulla ja rakennetta erilaisin rakennemittauksin. Lisäksi juustoista määritettiin kemiallinen koostumus ja mikrobiologinen laatu. Eri valmistusmenetelmillä valmistetut leikattavat tuorejuustot erosivat toisistaan tilastollisesti merkitsevästi joiltakin rakenteellisilta ja aistinvaraisilta ominaisuuksiltaan. Yksi leikattava tuorejuustonäyte koettiin kokonaisuudessaan miellyttävimmäksi kaikilta arvioitavilta ominaisuuksiltaan. Lisäksi rakennemittausten tulokset tukivat hyvin kuluttajien aistinvaraisia arviointeja. Tuorejuustojen säilyvyyttä tutkittiin siten, että rakenne- ja mikrobiologisista määrityksistä tehtiin toistomittaukset viiden viikon kuluttua valmistuksesta. Toistomittauksien avulla voitiin tarkastella rakenteen ja mikrobiologisten tulosten muuttumista säilönnän aikana. Säilyvyys oli pysynyt hyvänä lukuun ottamatta säkitysmenetelmässä mikrobien pesäkemääriä, joiden tulosta vääristivät maitohappobakteerit.
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(2019)People are eating a lot of ice cream all over the world and new products must be developed to create new options for consumers. Unilever, for whom this thesis has been made, is interested in developing new ice cream structures. The objective of the thesis was to explore different possibilities of ice cream structures and create two new interesting structures to the ice cream market; one with long, stretchy and chewy texture and one with high overrun (HOR) and light mouthfeel. The idea was to change the amounts, types and mixes of emulsifiers and stabilizers from the recipe. Additionally, process parameters, homogenisation and overrun, were changed from the current values. Hence, the purpose was to influence the size and amount of air bubbles and fat globules. The study was conducted at Unilever Sipoo, Ingman ice cream factory at their pilot plant. In the experimental part of the study, various versions of new ice cream structures were tested and compared to the reference product. After sensory analysis, it was decided to proceed with three versions of the HOR structure and two versions of the stretchy structure. At the end there were five versions of two new structures produced and analyzed with various tests. The analytical methods suitable and available for this study were viscosity measurement, shelf-life test, chemical test and melting test. Furthermore, there were small sensory analysis done during the study and comprehensive, final sensory analysis was done at the end of the study, for the final products. In conclusion, both of the new structures succeeded well. The “HOR E NAS 4” proved to be the best version of the structures. The melting profile of “HOR E NAS 4” ice cream corresponded the reference product. The results of the shelf-life test were positive: all the new structures survived better than the reference product. Sensory evaluation showed that the structures differed statistically significantly from each other and especially from the traditional ice cream, which was the aim of the study. The “HOR E NAS 4 “ was evaluated to be more firm and not so creamy as the reference product, which have to take in consideration in further investigations. “HOR E NAS 4” will be published on the ice cream market next year, as a new product.
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(2012)The aim of this study was to investigate the genetic relationships between conformation and performance traits in Finnish Warmblood riding horse population. The research material included the RHQT (riding horse quality test) results from the years 1996-2010 and the pedigree data for the horses. The RHQT results were received from the Finnish Breeders Association and the pedigree data was received from the Finnish trotting and breeding association’s horse register. The RHQT results consisted of 640 horses and the pedigree data consisted of 4 458 horses. The REML estimates of (co)variance components were calculated by VCE6 using multi trait model. Altogether there were six trait groups, which consisted of 27 different traits. Because of the large number of traits, the analyses were done in smaller subsets with two trait groups at the same time. The heritability estimates for the studied traits were quite high and the standard errors were small. The genetic correlations within each trait group were strong and positive. Thus it could be concluded that same genes or groups of genes affect all the traits within the trait group. The other explanation for this could be that in reality the judges have evaluated the same traits as different traits. The genetic correlations between conformation traits and all gait traits and dressage traits indicate that conformation can be used indirectly in the breeding of gait and dressage traits. Furthermore, it could be concluded that the genetic relationships between conformation and show-jumping traits are quite low. The genetic correlations between gait traits and show-jumping traits were low. The genetic correlations between gait traits and dressage traits were positive and strong. These strong and positive correlations indicate that the judged traits are actually same or very similar. From the results of this study can be concluded that all three different tests for show-jumping traits are actually measuring the same traits. Because of this one test would be adequate to produce the information of horses quality, capacity and breeding value. Moreover it can be concluded that there are genetic relationships between conformation and performance in Finnish Warmblood riding horse population. These discovered relationships can be used when breeding traits that have low heritabilities, such as the mechanic of movement in the walk or rideability. Furthermore, these results can be used to improve the judging methods in RHQT and other performance tests.
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(2007)The literature review deals with the composition of rye flour and the significance of en-zymes and sourdough in rye flour processing. The operational principles of twin screw extruders, the extrusion of grain based materials and the formation of aroma during grain based extrusion are also reviewed. The aim of this study was to determine the influence of the amount of powered rye sourdough and extrusion cooking parameters on the structure and properties of rye extrudate. Three process parameters were varied: content of rye sourdough powder, process temperature during the final stages of extrusion and revolution speed of the extruder's screws. A Box-Behnken's experimental design was used with 3 levels of dried sourdough powder content (0, 20 and 40%), 3 screws revolution speeds (200, 350 and 500 rpm) and 3 exit temperatures (120, 150 and 180°C). Feed rate was set at 4.0 kg/h and the moisture of the feed was 17.4%. A total of 15 experiments were perfomed. Pasting properties, acidity, acid value and D- and L-lactic acid concentration of full grain rye flour, dried rye sourdough flour and ground extrudate powder were determined. Acetic acid concentration of dried rye sourdough powder was also determined. Moisture content, expansion, texture, bubble sizes and colour of extrudate were determined. Extrusion cooking produce very different types of rye extrudates and the effect of process parameters on structure of extrudate was significant. When the pressure at the die was 30–40 bar, structure of extrudates were porous. Freeze dried extrudates were harder than extru-dates stored for one day at room temperature. Young's modulus decreased with increasing screws speed and processing temperature. Extrudate’s expansion increased as a function of increased revolution speed of screws and decreased processing temperature. As the content of dried sourdough increased, the bubble sizes of extrudate increased and also yellow (a) and red (b) colour and acidity of extrudates became stronger. Lightness (L) was statistical significantly higher when temperature was higher. As expected, the concentration of D- and L-lactic acid increased with increasing dried sourdough content. Decreased content of dried rye sourdough and slower revolution speed of screws increased cold peak viscosity signifi-cant. Peak and hold viscosities increased with slower revolution speed of the screws and decreased content of dried sourdough. Final viscosity and setback value increased signifi-cantly with slower revolution speed of the screws. The optimal extrudate, which was crispy and had a good flavour, was obtained when the content of dried sourdough powder was 20%, revolution speed of the screws was 500 rpm and processing temperature was 120°C.
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(2016)A range of different factors affect the composition of a sausage. The main objectives of this thesis were to research and define which factors have an impact on the firmness of the gel in sausages and to develop a method to define the composition of a warm sausage. Anchoring agents and fillers are added into sausages to improve the composition and flavour and to decrease the manufacturing costs. Most of the anchoring agents are proteins, however starch is also used. Starches are very viable anchoring agents. Gelatinised starches absorb or bind water and make it possible to have more water in a sausage. The research was composed of two phases in which the variables were the ingredients of the sausages. The factors that have an impact on the composition of sausages were analysed using statistical tests and variance analysis. In the first phase of the research a method to measure the firmness of a warm sausage was developed. The density of the gel was measured by sensory analysis and by Instron mechanical testing using the research method. The method was based on raising the core temperature of sausages above 49 °C to make the solid collagen soluble. Using a double boiler the core temperatures of the samples were adjusted to the desired level after which the samples were placed in the Instron mechanical tester in a styrox mold to limit the heat conduction. In addition to the mechanical tests a consumer survey to define the optimal eating temperature was included in the development of the research method. The results obtained by using the research method and the results from the sensory test had a correlation. In the future it is possible to skip sensory testing and use only this method to define the composition of a warm sausage. The method was used in the second phase of the research when studying the effects of different ingredients on the firmness of the gel in sausages. The results indicated that the composition of a sausage does undergo changes when heated.
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