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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Quince culture

Pratt, Benjamin Gildersleeve. January 1915 (has links)
"A research thesis for the Dept. of Pomology at Cornell University." / Bibliography: l. 32.
2

A study of the quince

Triggerson, Charles John, January 1910 (has links)
Minor thesis presented to the Dept. of Horticulture for the degree of Doctor of Philosophy. / Bibliography: leaves [33]-36.
3

An Analysis of Dominick Argento's "Peter Quince at the Clavier": the Music and Its Relationship to the Text

Gonzales, Cynthia I. (Cynthia Inez) 08 1900 (has links)
Dominick Argento (b. 1927) occupies an important position among American composers. This thesis discusses his 1980 choral work Peter Quince at the Clavier: Sonatina for Mixed Chorus and Piano Concertante. On the surface, the choral and piano parts of this four movement work often sound dissimilar. To create unity within this composition, Argento utilizes a small number of generative elements that govern the pitch, intervallic, and rhythmic dimensions of the composition. This thesis also discusses the relationship between the music and the text, a poem by Wallace Stevens (1879-1955).
4

Quince seed mucilage-based scaffold as a smart biological substrate to mimic mechanobiological behavior of skin and promote fibroblasts proliferation and h-ASCs differentiation into keratinocytes

Izadyari Aghmiuni, A., Heidari Keshel, S., Sefat, Farshid, Akbarzadeh Khiyavi, A. 22 February 2021 (has links)
Yes / The use of biological macromolecules like quince seed mucilage (QSM), as the common curative practice has a long history in traditional folk medicine to cure wounds and burns. However, this gel cannot be applied on exudative wounds because of the high water content and non-absorption of infection of open wounds. It also limits cell-to-cell interactions and leads to the slow wound healing process. In this study to overcome these problems, a novel QSM-based hybrid scaffold modified by PCL/PEG copolymer was designed and characterized. The properties of this scaffold (PCL/QSM/PEG) were also compared with four scaffolds of PCL/PEG, PCL/Chitosan/PEG, chitosan, and QSM, to assess the role of QSM and the combined effect of polymers in improving the function of skin tissue-engineered scaffolds. It was found, the physicochemical properties play a crucial role in regulating cell behaviors so that, PCL/QSM/PEG as a smart/stimuli-responsive bio-matrix promotes not only human-adipose stem cells (h-ASCs) adhesion but also supports fibroblasts growth, via providing a porous-network. PCL/QSM/PEG could also induce keratinocytes at a desirable level for wound healing, by increasing the mechanobiological signals. Immunocytochemistry analysis confirmed keratinocytes differentiation pattern and their normal phenotype on PCL/QSM/PEG. Our study demonstrates, QSM as a differentiation/growth-promoting biological factor can be a proper candidate for design of wound dressings and skin tissue-engineered substrates containing cell.
5

Estudio de prefactibilidad para la instalación de una planta de producción de agua de membrillo (Cydonia oblonga)

Barba-Claros, Gloria-Elena, Portal-Iberico, David-Emanuel January 2016 (has links)
El presente estudio de prefactibilidad evalúa la viabilidad comercial, técnica, económica y financiera de la instalación de una planta productora de agua de membrillo en la provincia de Lima. La demanda del proyecto para el año diez es 6.608.015 botellas de agua de membrillo, a un precio unitario de S/. 1,88. La planta estará ubicada en Lima Metropolitana, en el distrito de Santa Anita y tendrá una capacidad de 983 botellas por hora. / The present prefeasibility study evaluates the commercial, technical, economic and financial viability for the installation of a quince water factory in the province of Lima. The demand of the project for the tenth year is 6.608.015 bottles of quince water, with a price of S/. 1,88 per bottle. The factory will be located in Santa Anita district in Lima Metropolitana and it will have a capacity of 983 bottles per hour. / Trabajo de investigación
6

Uticaj osmotskog i konvektivnog sušenja na fizičkeosobine dunje (Cydonia oblonga Mill.) / Influence of osmotic and convective drying on thephysical properties of quince (Cydonia oblonga Mill.)

Radojčin Milivoj 19 May 2015 (has links)
<p>Važnost istraživanja fizičkih osobina ogleda se u tome, &scaron;to su neke od tih osobina prvo &scaron;to<br />se uočava na su&scaron;enom voću. Druge fizičke osobine spoznaju se tokom konzumiranja. Osim<br />toga, fizičke osobine su i od značaja prilikom projektovanja opreme za preradu<br />poljoprivrednih proizvoda. Predmet istraživanja doktorske disertacije su promene fizičkih<br />osobina dunje tokom osmotskog i konvektivnog su&scaron;enja. Istraživane su promene sledećih<br />osobina: vlažnosti, zapremine, mehaničkih osobina i boje. Kao dodatak osnovnim merenjima<br />obavljene su hemijska i senzorska analiza finalnog proizvoda. Eksperiment osmotskog<br />su&scaron;enja obavljen je kao dvofaktorni. Faktori eksperimenta su temperatura i koncentracija<br />osmotskog rastvora. U eksperimentu je kori&scaron;ćena dunja sorte leskovačka. Ovu sortu odlikuje<br />prijatna aroma, oblik i dimenzije pogodne za su&scaron;enje.<br />Disperzionom analizom rezultata merenja fizičkih osobina tokom eksperimenta<br />osmotskog su&scaron;enja potvrđeno je da izabrani nivoi temperature i koncentracije osmotskog<br />rastvora utiču na promenu vlažnosti dunje tokom 180 minuta osmotskog su&scaron;enja. U slučaju<br />povećanja mase suve materije disperzionom analizom potvrđen je statistički značajan uticaj<br />koncentracije i interakcije koncentracije i temperature na promenu ispitivane veličine.<br />Najintenzivnije promene vlažnosti i povećanja suve materije izmerene su u prvih 20 minuta<br />osmotskog su&scaron;enja.<br />Promena oblika dunje u formi kocke, do kojih dolazi tokom osmotskog su&scaron;enja je<br />anizotropna. Razlog anizotropnog skupljanja tkiva može biti orijentacija vlakana i<br />nehomogena struktura materijala. Promena zapremine izražena je zapreminskim skupljanjem<br />SV. Izvedena je jednačina kojom je utvrđena zavisnost promene zapremine od količine<br />razmenjene materije tokom osmotskog su&scaron;enja. Najveća promena zapremine izmerena je pri<br />osmotskom su&scaron;enju pri najvi&scaron;im vrednostima temperature i koncentracije osmotskog<br />rastvora.<br />Mehaničke osobine dunje tokom osmotskog su&scaron;enja predstavljene su sa dva pokazatelja,<br />otporno&scaron;ću na razaranje i modulom elastičnosti. Otpornost na razaranje je u ovoj tezi<br />originalno predstavljena parametrom f. Ovaj parameter predstvalja relativnu promenu sile<br />razaranja tokom osmotskog su&scaron;enja. Disperzionom analizom utvrđen je uticaj temperature<br />osmotskog rastvora na mehaničke osobine dunje. Osmotski rastvor temeperature 60oC<br />izaziva omek&scaron;avanje tkiva dunje. Međutim, omek&scaron;avanje tkiva dunje pozitivno utiče na<br />čvrstoću krajnjeg proizvoda. Kao drugi pokazatelj mehaničkih osobina upotrebljen je modul<br />elastičnosti. Promene modula elastičnosti slične su promenama f parametra. Na osnovu<br />promena oba pokazatelja mogu se doneti isti zaključci o uticaju faktora eksperimenta na<br />mehaničke osobine tkiva dunje.<br />Tkivo dunje je izloženo vazduhu tokom konvektivnog su&scaron;enja intenzivno menja boju. U<br />eksperimentu je upotrebljen sumpordioksid kao za&scaron;tita od tamnjenja tkiva. Ukupna promena<br />boje najveća je na uzorcima dunje koji su su&scaron;eni rastvorom koncentracije 65oBx. Međutim,<br />tokom konvektivnog su&scaron;enja ističe se pozitivan uticaj ovog tretmana na promenu boje dunje.<br />Veća količina saharoze koja se zadržava na povr&scaron;ini uzoraka dunje predstavlja barijeru<br />između između materijala i vazduha i spračava tamnjenje tkiva.<br />Regresionom analizom rezultata merenja promene vlažnosti, zapremine i boje pronađeni<br />su empirijski modeli koji opisuju merene veličine tokom osmotskog su&scaron;enja. Jednačine<br />odabrane za modelovanje promene vlažnosti pro&scaron;irene su uticajnim faktorima u<br />bezdimenzionalnom obliku. Pro&scaron;irenjem matematičkih modela stiče se njihova univerzalnost<br />u opsegu istraživanih vrednosti temperature i koncentracije osmotskog rastvora. Primenjeni<br />modeli mogu se uspe&scaron;no koristiti za predviđanje svih merenih veličina. Uspe&scaron;nost modela<br />potvrđena je visokim vrednostima koeficijenta korelacije i niskim vrednostima srednje<br />procentualne gre&scaron;ke.<br />Senzorskim analizama obavljenim panelnim ispitivanjem, uzorci tretirani osmotskim<br />rastvorom ocenjeni su kao kvalitetniji od onih koji su samo konvektivno osu&scaron;eni.<br />Poređenjem rezultata kvantitativnih i kvalitativnih analiza može se zaključiti da osmotsko<br />su&scaron;enje kao predtretman konvektivnom su&scaron;enju pozitivno utiče na kvalitet su&scaron;ene dunje kao<br />finalnog proizvoda.<br />&nbsp;</p> / <p>The importance of researching physical properties lies in the fact that some of these<br />properties are what we first notice about dried fruit. Other physical properties are<br />experienced during consumption. Moreover, physical properties are also important when<br />designing equipment for processing agricultural products. The subject of the research in this<br />doctoral dissertation is changes in physical properties of quince during osmotic and<br />convective drying. The investigation included changes in the following properties: moisture,<br />volume, mechanical properties and colour. Apart from the basic measurements, the research<br />also included chemical and sensory analyses of the final product. The experiment of osmotic<br />drying was performed as a two-factor experiment, while factors were the temperature and the<br />concentration of osmotic solution. The variety of quince used in the experiment was<br />&ldquo;Leksovačka&rdquo;, which is a variety with a pleasant aroma, and the shape and dimensions<br />suitable for drying.<br />Dispersion analysis of the measured results in the experiment of osmotic drying showed<br />that the temperature and concentration of osmotic solution affect the changes in moisture of<br />quince during 180 minutes of osmotic drying. In the case of the increased mass of dry matter,<br />analysis of variance pointed to statistically significant effect of concentration and interaction<br />of concentration and temperature on the change in the examined size. The most intense<br />changes in moisture and increase of dry matter were measured in the first 20 minutes of<br />osmotic drying.<br />The change of the shape of quince into the shape of a cube, which occurs during osmotic<br />drying, is anisotropic. The reason of anisotropic shrinkage of tissue can be fibre orientation<br />and inhomogeneous structure of the material. The volume change is expressed in volumetric<br />shrinkage SV. The equation derived was used to determine the dependence of the change in<br />volume on the amount of the matter exchanged during osmotic drying. The greatest change<br />in volume was measured during osmotic drying at the highest values of temperature and the<br />highest values of concentration of osmotic solution.<br />Mechanical properties of quince during osmotic drying were represented by two<br />indicators: resistance to rupture and modulus of elasticity. Resistance to rupture in this thesis<br />was originally presented by the parameter f. This parameter represents a relative difference of<br />force of rupture. Dispersion analysis determined the effect of the temperature of osmotic<br />solution on mechanical properties of quince. The solution temperature of 60oC causes<br />softening of the quince tissue. However, softening of the tissue has positive effects on<br />firmness of the final product. The other indicator of mechanical properties was modulus of<br />elasticity. The changes in the modulus of elasticity are similar to the changes of the<br />parameter f. The changes in both indicators lead to the same conclusions about the impact of<br />the factors of the experiment on the mechanical properties of quince tissue.<br />Quince tissue exposed to air changes its colour intensely. In this experiment, sulphur<br />dioxide is used as protection against darkening of the tissue. The total colour change was the<br />greatest in the quince samples dried using a solution with the concentration of 65oBx.<br />However, during convective drying one can see the positive impact of this treatment on the<br />colour change in quince. A larger amount of saccharose which is retained on the surface of<br />the samples acts as a barrier between the material and the air, preventing darkening of the<br />tissue.<br />Regression analysis of the measured results of the changes in moisture, volume and<br />colour, generated empirical models that describe the measured values during osmotic drying.<br />The equations selected for modelling of moisture changes were extended to include<br />influential factors in dimensionless form. What is achieved by extending the mathematical<br />models is universality of the models in the range of the investigated values of temperature<br />and concentration of osmotic solution. The used models can be successfully applied for<br />prediction of all of the measured values. The successfulness of the model is confirmed by<br />high values of the correlation coefficient and low values of the mean percentage error.<br />Sensory analyses performed using panel testing showed that the samples treated with osmotic<br />solution were evaluated to be of higher quality than the samples that were only convectively<br />dried. By comparing the results of quantitative and qualitative analyses, it can be concluded<br />that osmotic drying, as a pre-treatment to convective drying, positively affects the quality of<br />dried quince as a final product.</p>
7

Stanovení vitaminu C kapalinovou chromatografií v plodech jednotlivých odrůd méně známých druhů ovoce / Determination of C vitamin by HPLC in fruits of individual cultivars of less known kinds of fruits

Cetkovská, Jitka January 2009 (has links)
Diploma thesis deals with determination of vitamin C in various cultivars of sea buckthorn (Hippophae rhamnoides, L.) and quince (Cydonia oblonga, Mill.). In theoretical part, there are mentioned basic information about these less known fruit species, their medically significant substances and utilization of these fruits. Various methods for determination of vitamin C are discussed with focus on HPLC and extraction of vitamin C from the matrix. In experimental part, the most suitable column (Gemini C18, 150 x 4,6 mm; 5 m) was chosen from six various columns. Analysis of vitamin C in various cultivars of quince and sea buckthorn fruits were carried out on this column. The various types of matrix preparation and two different separation systems (method with oxalic acid and system with phosphate buffer and methanol as a mobile phases) were investigated too. Vitamin C was determined as an ascorbic acid.
8

Stanovení některých nutričních faktorů ve vybraných druzích ovoce / Determination of some nutrition factors in selected kinds of fruit

Smělá, Margita January 2011 (has links)
Diploma thesis is concerned with determination of some nutrion factors and vitamin C in various cultivars of apples (Pirus Malus, L.) and quinces (Cydonia oblonga, Mill.). In theoretical part there are described general characterization in selected kinds of fruits, their medically significant sunstances and utilization of these fruits. Main focus is paid to vitamin C. There are described its chemical properties and effect for human health. Various methods for determination of some nutrion factors with focus on determination of vitamin C by high-performance liquid chromatography. In experimental part, total of 27 various cultivars of aplles and 16 various cultivars of quinces were analyzed. These cultivars are from grower station Faculty of garden of Mendel university. For determitation vitamin C was used by high-performance liquid chromatography. Vitamin C was determination as an ascorbic acid. Some nutrion factors were analyzed in experimental part. There were analyzed dry matter, total flavonoids, total phenolics and titratable acid in various cultivars of apples and quinces. There were compared of some various cultivars after representation and content of significant substances as result. The last part of thesis was sensory analysis of apples.
9

ESTABELECIMENTO IN VITRO DE MARMELEIRO JAPONÊS (Chaenomeles sinensis Koehne) CV ANDRAMIG

Figueiredo, Geórgea Soares 06 March 2009 (has links)
Made available in DSpace on 2014-08-20T14:22:08Z (GMT). No. of bitstreams: 1 Dissertacao_Georgea_Soares_Figueiredo.pdf: 728913 bytes, checksum: b001e52b25d78faa26942f0b6de87631 (MD5) Previous issue date: 2009-03-06 / The Japanese quince (Chaenomeles sinensis Koehne) can be used as rootstocks for quince, pear, loquat trees and as cultivar canopy. The use of quince by seeds, as rootstocks for other quince species and cultivars, has been shown viable. However, the inconvenient in the sexual reproduction is obtaining of not uniform seedlings, since it is not desired in the commercial plantations establishment due gene segregation. The seedlings production technology for Japanese quince by vegetative propagation is not defined, due low percentage of rooting. Thus, the tissue culture presents as a viable alternative in the clonal orchards development or seedlings commercial production. Experiments were performed to determine a protocol of in vitro establishment this specie, where was tested the disinfectant with chlorine appropriate for vegetal material, as well as cytokinin, flask cover, salt concentration of culture medium, culture medium, BAP cytokinin concentration and light quality. It could be conclude that calcium hypochlorite disinfectant is effective in the explants disinfestations, and the BAP provides better results in the establishment than 2iP and Zea cytokinins. Sealed flasks with cotton instead aluminum, reduce the explant oxidation and the original salt concentration of MS medium promotes better explant establishment. The WPM medium showed higher results than MS medium and BAP at 1mg.L-1 or 2mg.L-1 concentration promotes an increase in the number and length of sprouting, as well as the use of red light instead white and green light. / O marmeleiro japonês Chaenomeles sinensis Koehne pode ser utilizado como porta-enxerto para marmeleiros, pereiras, nespereiras e também como cultivar copa. O uso deste marmeleiro via seminífera, como porta-enxerto para outras espécies e cultivares de marmelo, tem se mostrado viável, o inconveniente na reprodução sexual é a obtenção de plântulas desuniformes, o que não é desejado no estabelecimento de plantios comerciais, devido à segregação gênica. A tecnologia de produção de mudas para o marmeleiro Japonês por propagação vegetativa não está ainda definida, devido a baixa porcentagem de enraizamento, sendo assim a cultura de tecidos apresenta-se como uma alternativa viável na formação de pomares clonais ou produção comercial de mudas. Foram realizados experimentos a fim de determinar um protocolo de estabelecimento in vitro desta espécie, onde foi testado o desinfestante a base de cloro adequado a desinfestação do material vegetal, bem como o a citocinina, tipo de vedação dos frascos, concentração salina do meio de cultura, meio de cultura, concentração da citocinina BAP e qualidade de luz. A partir dos resultados obtidos pode-se concluir que o desinfestante hipoclorito de cálcio é eficiente na desinfestação dos explantes, e a citocinina BAP promove melhores resultados no estabelecimento, comparada as citocininas 2iP e Zea. Frascos vedados com algodão, ao invés de alumínio, reduzem a oxidação dos explantes e o meio MS na sua concentração salina original promoveu melhor estabelecimento dos explantes. O meio WPM demonstrou resultados superiores ao meio MS e a citocinina BAP na concentração de 1mg.L-1 ou 2mg.L-1 promove aumento no número e comprimento das brotações, assim como a utilização de luz vermelha quando comparada a luz branca e a luz verde.
10

Kinetika kombinovanog sušenja dunje (Cydonia oblonga Mill.) / Kinetics of combined dryingquince (Cydonia oblonga Mill.)

Stojanović Čedomir 25 June 2014 (has links)
<p>Su&scaron;enje dunje kao voćne vrste u praksi nije uobičajeno, zbog povi&scaron;ene vrijednosti<br />tvrdoće i čvrstoće. Prethodna istraživanja su&scaron;enja dunje, pokazala su da se osmotskim<br />su&scaron;enjem u okviru kombinovane tehnologije su&scaron;enja dobijaju povoljnije mehaničke<br />osobine su&scaron;enih proizvoda. Na osnovu plana obavljeni su eksperimenti osmotskog i<br />konvektivnog su&scaron;enja dunje u obliku četvrtina. Eksperiment osmotskog su&scaron;enja je<br />obavljen kao trofaktorni, gdje su uticajni faktori: temperatura rastvora, koncentracija<br />rastvora i vrijeme trajanja su&scaron;enja. TakoĎe, eksperiment konvektivnog su&scaron;enja je obavljen<br />kao trofaktorni, a uticajni faktori su: primjenjeni predtretman, temperature vazduha za<br />su&scaron;enje i brzina strujanja vazduha ispred sloja.<br />Na osnovu rezultata mjerenja eksperimenta osmotskog su&scaron;enja, zaključeno je da sa<br />porastom temperature i koncentracije rastvora postiže se veća brzina su&scaron;enja, &scaron;to se i<br />očekivalo. Disperzionom analizom osmotskog su&scaron;enja je ispitan uticaj faktora na brzinu<br />su&scaron;enja i zapreminsko skupljanje četvrtina dunje. Sa statističkom vjerovatnoćom od 99%<br />je dokazano da postoji uticaj svih faktora na brzinu su&scaron;enja uzoraka. Dokazano je sa<br />statističkom vjerovatnoćom od 99% da vrijeme trajanja osmotskog su&scaron;enja ima uticaj na<br />zapreminsko skupljanje četvrtina dunje, dok uticajni faktori temperatura i koncentracija<br />rastvora imaju uticaj sa statističkom vjerovatnoćom od 95%.<br />Analizom rezultata mjerenja veličina tokom eksperimenta konvektivnog su&scaron;enja<br />evidentno je da se sa vi&scaron;om temperaturom vazduha postiže brže sniženje vlažnosti<br />četvrtina dunje. Povećanjem vremena trajanja osmotskog predtretmana, smanjuje se<br />brzina konvektivnog su&scaron;enja. UtvrĎeno je da kori&scaron;ćenje osmotskog predtretmana sa<br />vi&scaron;om temperaturom rastvora i većom koncentracijom rastvora dovodi do smanjenja<br />brzine konvektivnog su&scaron;enja. Na osnovu disperzione analize konvektivnog su&scaron;enja sa<br />statističkom vjerovatnoćom od 99% dokazano je da postoje uticaji predtretmana i<br />temperature vazduha na brzinu su&scaron;enja i zapreminsko skupljanje četvrtina dunje. Uticaj<br />faktora brzine vazduha ispred sloja materijala nije dokazan disperzionom analizom, ali je<br />na osnovu kinetički krivih evidentan uticaj ovog faktora na brzinu su&scaron;enja, pri vi&scaron;im<br />vlažnostima materijala i vi&scaron;oj temperaturi konvektivnog su&scaron;enja. Najvjerovatniji razlog<br />ovakvih rezultata disperzione analize su male vrijednosti brzine vazduha za su&scaron;enje,<br />odnosno njihova mala razlika vrijednosti (0,5 m/s).<br />Kinetika prenosa mase tokom kombinovane tehnologije su&scaron;enja dunje u formi<br />četvrtine je matematički opisana, modelovanjem kinetike osmotskog su&scaron;enja i kinetike<br />konvektivnog su&scaron;enja. U okviru kinetike osmotskog su&scaron;enja četvrtina dunje, obavljeno je<br />matematičko modelovanje promjene vlažnosti u odnosu na suvu bazu i modelovanja<br />zapreminskog skupljanja. Za kinetiku konvektivnog su&scaron;enja četvrtina dunje, obavljeno je<br />matematičko modelovanje promjene vlažnosti u odnosu na suvu bazu tokom vremena<br />konvektivnog su&scaron;enja. Za svaku veličinu koja se modeluje usvojeno po tri matematička<br />modela, a modeli su pro&scaron;ireni uticajnim faktorima u bezdimenzionom obliku. Izvedeni<br />modeli su imali dobro slaganje sa eksperimentalnim rezultatima, &scaron;to pokazuju visoke<br />vrijednosti koeficijente korelacije. Primjena svih modela je jednostavna, gdje je uz pomoć<br />standardnih računara moguće brzo izračunavanje svih modelovanih veličina.<br />Primjenom osmotskog predtretmana u kombinovanoj tehnologiji su&scaron;enja dunje,<br />dobijaju se neke pozitivne osobine su&scaron;enog proizvoda. Smanjenje zapremine je manje<br />izraženo, nego primjenom samo konvektivnog su&scaron;enja. Vlažnost u voćnom tkivu je<br />ravnomjernije rasporeĎena i manje je presu&scaron;ivanje spoljnjih slojeva voćnog tkiva.<br />Stvaraju se manji unutra&scaron;nji naponi izmeĎu slojeva tkiva, uslijed čega nastaju manje<br />deformacije oblika. U povr&scaron;inskom sloju voćnog tkiva postoje adsorpcione veze vlage,<br />rastvorka i suve materije, a ove veze utiču na povećanje vrijednosti vlažnosti pri kojima<br />se osu&scaron;eni proizvod bezbjedno skladi&scaron;ti.</p> / <p>Drying of the quince as a fruit species is not common in practice due to its increased hardness<br />and firmness. Previous researches on quince drying have indicated that osmotic drying, within<br />the combined drying technology, enables favourable mechanical properties of dried products.<br />Planned experiments of the osmotic and convective drying of quince quarters were conducted.<br />The osmotic drying experiment was based on three significant experimental factors: the<br />temperature of osmotic solution, the concentration of osmotic solution, and the duration of<br />osmotic drying. The convective drying experiment was also based on three experimental<br />factors entailing the applied pretreatment, the temperature of drying air and the velocity of<br />drying air in front of material layers.<br />The measurement results obtained during the osmotic drying experiment indicate that an<br />increase in the temperature and the concentration of osmotic solution accelerates the drying<br />process, as expected. A dispersion analysis of the osmotic drying indicated the effects of<br />experimental factors on the drying speed and the volume shrinkage of quince quarters. With a<br />statistical probability of 99%, it was proven that all factors influence the speed of drying.<br />Moreover, with a statistical probability of 99%, it was proven that the duration of osmotic<br />drying influences the volume shrinkage of quince quarters, whereas the significant factors such<br />as the temperature and the concentration of osmotic solution exert influence with a statistical<br />probability of 95%.<br />The analysis of measurement results obtained during the convective drying experiment shows<br />that an increase in the air temperature accelerates a decrease in the moisture content of quince<br />quarters. An increase in the duration of osmotic pretreatment decelerates the convective drying<br />process. It was determined that the application of the osmotic pretreatment with higher<br />solution temperature and concentration decelerates the convective drying. On the basis of a<br />dispersion analysis of the convective drying with a statistical probability of 99%, it was proven<br />that the pretreatment and the air temperature affect the speed of drying and the volume<br />shrinkage of quince quarters. The effects of the air velocity in front of the material layer was<br />not determined by means of the dispersion analysis, nevertheless kinetic curves indicate the<br />influence of this factor on the drying speed, especially in the instance of higher moisture<br />content of the material and higher temperature of the convective drying. The most probable<br />causes of such dispersion analysis results are low values of the drying air velocity, i.e. a slight<br />difference in the values (0.5 m/s).<br />The kinetics of mass transfer during the combined drying of quince quarters was<br />mathematically described by means of the modelling of the kinetics of osmotic drying and the<br />kinetics of convective drying. The kinetics of osmotic drying of quince quarters was expressed<br />via the mathematical modelling of moisture content change in relation to dry basis and the<br />modelling of volume shrinkage. The kinetics of convective drying of quince quarters was<br />expressed via the mathematical modelling of moisture content change in relation to dry basis<br />during the convective drying. Three mathematical models were established for every modelled<br />value, and the models were extended by significant non-dimensional experimental factors. The<br />developed models had a good fit with the experimental results, which was indicated by the<br />high values of the correlation coefficient. The application of all models is simple and standard<br />personal computers can be used for rapid calculations of modelled values.<br />The application of the osmotic pretreatment in the combined quince drying enables<br />favourable properties of dried products. Volume shrinkage is slighter in comparison with the<br />convective quince drying. The moisture content in the fruit tissue is more evenly distributed<br />and the dehydration of the outer layers of the fruit tissue is lower. The tension between the<br />layers of the tissue is reduced thus reducing the shape defects. Within the surface layers of fruit<br />tissues, the adsorption bonds of moisture, solute and dry matter are formed. These bonds<br />increase the moisture content value, which enables the safe storage of dry products.</p>

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