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1
Shi, Xun. "Effect of Processing and Formulations on Cocoa Butter". The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1420772706.
Testo completo
2
Sonwai, Sopark. "The effect of shear on the crystallisation of cocoa butter". Thesis, University of Cambridge, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.619626.
Testo completo
3
Talhat, Amanda Makhpal. "Polymorphic forms of cocoa butter as a function of origin and processing conditions". Thesis, University of Cambridge, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708422.
Testo completo
4
di, Bari Vincenzo. "Large deformation and crystallisation properties of process optimised cocoa butter emulsions". Thesis, University of Birmingham, 2015. http://etheses.bham.ac.uk//id/eprint/6305/.
Testo completoAbstract (sommario):
The objectives of the research presented in this thesis were: (1) optimise the processing conditions for the production of water-in-cocoa butter emulsions; (2) understand the role of water droplets on the large deformation behaviour and crystallisation properties of emulsified systems. Results showed that a scraped surface heat exchanger could be used to produce tempered emulsions with a small average droplet size (~3 µm). In all systems stability was provided by the emulsifier and fat crystals forming a network both in the bulk and at the interface of the water droplets. Characterisation of the large deformation properties of emulsions showed that the elastic behaviour remained constant at low aqueous phase percentages while the strength at fracture decreased. This result suggests that water droplets act as stress-concentrator elements, which is probably due to their partial sintering with the bulk network. Results of crystallisation experiments have shown that the effect of droplets on kinetics of crystallisation depends on the degree of supercooling: only at relatively high temperatures (15, 20 °C) the dispersed droplets increased the kinetics of crystallisation compared to bulk cocoa butter (CB). With respect to polymorphic evolution, emulsified systems evolved faster toward more stable forms than bulk CB at all temperatures.
5
Wei, Daijing. "Effect of emulsifiers on the crystallization kinetics of triglycerides and cocoa butter /". For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2005. http://uclibs.org/PID/11984.
Testo completo
6
Fevola, Martina. "Quality evaluation of cocoa beans produced by smallholder cocoa farmers in Ghana". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
Cerca il testo completoAbstract (sommario):
Il cacao (Theobroma cacao L.) è un’importante coltura a livello mondiale. La sua produzione è alla base dell’economia della maggior parte dei paesi produttori e dei profitti di molte industrie dolciarie.
Attualmente, circa il 70% delle fave di cacao nel mondo è raccolto in Africa. Il Ghana è il secondo paese produttore dopo la Costa d’Avorio. La maggior parte del cacao proviene da piccoli agricoltori che spesso usano sistemi di coltivazione obsoleti e poco organizzati.
La crescente domanda di cacao nel mercato mondiale ha aumentato l’attenzione su una produzione sostenibile attraverso una serie di miglioramenti per la coltivazione e i processi post-raccolta. Questa tesi fa parte di un progetto che ha come obiettivo a lungo termine quello di incrementare la produzione di cacao di alta qualità da parte di piccoli coltivatori in Africa occidentale.
Per questo lavoro sono state esaminate fave di cacao prodotte da 30 piccoli agricoltori di sei regioni del Ghana. I campioni sono stati analizzati e comparati sotto forma di fave di cacao intere, in polvere e liquore di cacao.
I risultati hanno rilevato alcuni difetti nel processo di fermentazione evidenziati dai bassi livelli dell’ indice di fermentazione e dalla presenza di Ocratossina A. Dai risultati si evince anche che le fave di cacao prodotte in Ghana hanno grandi dimensioni, alto contenuto di grassi e presentano note aromatiche fruttate.
7
Moraes, Ingrid Franco de Oliveira 1986. "Avaliação e adequação do comportamento de gorduras equivalentes de manteiga de cacau para chocolates". [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254677.
Testo completoAbstract (sommario):
Orientador: Lireny Aparecida Guaraldo GonçalvesDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
Made available in DSpace on 2018-08-21T23:51:40Z (GMT). No. of bitstreams: 1 Oliveira_IngridFrancode_M.pdf: 12512639 bytes, checksum: 63474efdec388007cba17547f09ce8c9 (MD5) Previous issue date: 2013
Resumo: Gorduras equivalentes de manteiga de cacau (CBEs) são utilizadas nas formulações de chocolates, substituindo parte da manteiga de cacau (MC). Embora as CBEs sejam compatíveis com a MC é importante um estudo detalhado a fim de se conhecer as propriedades de cristalização, fusão e estabilidade dos cristais, uma vez que as mesmas alteram a qualidade dos chocolates. Este estudo objetivou aumentar o conhecimento sobre CBEs e propor alteração do comportamento de fusão e cristalização de uma CBE escolhida. Sendo assim, foram caracterizadas quatro CBEs, com base em uma MC usada como padrão. As análises utilizadas para a caracterização foram índices de qualidade e de identidade, composição em ácidos graxos, índice de iodo, índice de saponificação, ponto de fusão, teor de sólidos por Ressonância Magnética Nuclear (RMN), isoterma de cristalização a 17,5°C por RMN, eventos de cristalização por Calorimetria Diferencial de Varredura (DSC), eventos de fusão por DSC em quatro tempos de armazenamento a 25°C (0, 4, 8 e 24 horas) e análise por difração de Raios-X. Adicionou-se 0,3% de triestearato de sorbitana (STS) às CBEs e o efeito do STS foi avaliado por meio de isotermas a 17,5°C, eventos de fusão por DSC em quatro tempos de armazenamento a 25°C (0, 4, 8 e 24 horas) e análise por difração de Raios-X. Ao final do estudo, foram elaboradas três formulações de chocolate: chocolate com 12% de MC, chocolate com 12% de CBE e chocolate com 12% de CBE com adição de 0,3% STS. Os chocolates foram avaliados quanto à viscosidade plástica, limite de fluidez, evento de fusão, tensão de ruptura (snap test) e microscopia eletrônica de varredura (MEV). A MC e as CBEs estudadas apresentaram-se dentro dos padrões de qualidade e identidade e os teores de ácidos graxos e triacilgliceróis analisados individualmente diferiram, destacando que as CBEs apresentaram maiores discrepâncias nos teores de POP (1, 3 palmitoil oleoil glicerol) e SOS (1,3 estearoil oleoil glicerol). As amostras apresentaram diferentes comportamentos de fusão, cristalização, estabilização e polimorfismo. O uso de STS promoveu elevação das curvas de cristalização a 17,5°C acarretando em perfis mais similares ao da MC em duas CBEs, embora não tenha alterado o polimorfo final das amostras após a estabilização. O uso de 0,3% STS em chocolate promoveu elevação do snap, embora não tenha sido verificada alteração na viscosidade plástica e no limite de fluidez dos chocolates. Diferentes estruturas foram visualizadas nas imagens realizadas em MVE
Abstract: Cocoa butter equivalent (CBEs) are used in chocolate formulations, replacing part of the cocoa butter (CB). Although there is compatibility between CBEs and cocoa butter, it is important a detail study that aims to know the properties of crystallization, melting and stability of the crystals, once it modifies the quality of the chocolate. This study intends to increase knowledge of CBEs and modify the melting and crystallization behavior of a selected CBE. Present study characterized and differentiated four CBEs and a standard CB. Analyzes used for the characterization and differentiation were free fatty acids, peroxide value, fatty acid composition, iodine value, saponification value, melting point, solid fat content by Nuclear Magnetic Resonance (NMR), isothermal crystallization at 17.5 ° C by NMR, crystallization events by Differential Scanning Calorimetry (DSC), fusion events by DSC during storage in four times at 25 ° C (T0 ¿ 0 hour, T1 ¿ 4 hours, T2 - T3 and 8 hours - 24 hours) and analysis by X-rays diffraction. It was added to CBE 0.3% tristearate sorbitan (STS) and the effect of STS addiction was evaluated by isotherms at 17.5 ° C, fusion events by DSC at four times of storage at 25 °C (T0 ¿ 0 hour, T1 ¿ 4 hours, T2 - 8 hours and T3 - 24 hours ) and analysis by X-rays diffraction. At the end of the study, three formulations of chocolates were prepared: chocolate with 12% CB, chocolate with 12% CBE and chocolate with 12% CBE and 0.3% STS. Chocolates were evaluated by plastic viscosity, shear stress, fusion event, texture (snap test) and scanning electron microscopy (SEM). The CB and CBEs studied were within the standards of quality and identity and fatty acids and triacylglycerols analyzed individually differed, emphasizing that the CBEs had differences in the levels of POP (palmitoil oleoil glycerol) and SOS (stearoyl oleoyl glycerol). The samples showed different behaviors melting, crystallization, stabilization and polymorphism. The use of STS caused increase of the crystallization curves at 17.5 ° C resulting in profiles most similar to the CB in two CBEs, although not changed polymorph end of the samples after equilibration. The use of 0.3% STS in chocolate increased the snap, though not verified change in plastic viscosity and fluidity limit of chocolates. Different structures were visualized in the images of SEM
Mestrado
Tecnologia de Alimentos
Mestra em Tecnologia de Alimentos
8
Wang, Hao Wang. "Oil Diffusion in Different Cocoa Butters Using Magnetic Resonance Imaging". The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1461239233.
Testo completo
9
McGauley, Sara Elizabeth. "The relationship between polymorphism, crystallization kinetics, and microstructure of statically crystallized cocoa butter". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ61926.pdf.
Testo completo
10
Ladd, Parada Marjorie. "The effects of pressure and thermal history on the crystallisation of cocoa butter". Thesis, University of Leeds, 2018. http://etheses.whiterose.ac.uk/22114/.
Testo completo
11
Silva, Thais Lomonaco Teodoro da 1989. "Gorduras alternativas no comportamento de cristalização da manteiga de cacau e do chocolate". [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254702.
Testo completoAbstract (sommario):
Orientadores: Lireny Aparecida Guaraldo Gonçalves, Renato GrimaldiDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: A manteiga de cacau (MC) é uma gordura natural extremamente importante para formulação de chocolate, mas devido à dificuldade em seu acesso e volatilidade de seus preços outras gorduras alternativas têm sido estudadas e produzidas a fim de substituí-las, como as gorduras equivalentes (Cocoa Butter Equivalent-CBE) e as substitutas (Cocoa Butter Substitutes-CBS). Entretanto as características de cristalização e sensoriais da MC promovidas no chocolate são muito peculiares, além disto, pode ocorrer uma incompatibilidade entre as gorduras sucedâneas o que ocasionará defeitos no chocolate como o fat bloom. O objetivo desse trabalho foi estudar a cristalização da MC, CBE, CBS, bem como entre estas misturas, a fim de se obter uma fração o mais semelhante possível à MC pura para elaboração de chocolates amargos, e a partir da avaliação destes chocolates, estudar a influência dessas gorduras na formação do fat bloom. As misturas elaboradas foram baseadas no teor total de MC presente no chocolate (MC adicionada e do liquor) e as concentrações estudadas variaram de 5%, 10%, 15%, 20% e 37,5% da CBE ou CBS na MC. As matérias-primas e as misturas foram caracterizadas mediante composição em ácidos graxos, composição triacilglicerólica, isotermas de cristalização, teor de sólidos, microestrutura, comportamento térmico, polimorfismo, consistência e ponto de fusão. Para verificar o efeito da adição dessas gorduras na qualidade do chocolate e resistência ao fat bloom amostras produzidas foram armazenados sob duas condições, 100 dias por 20°C e seis ciclos de 48h com 24h a 20°C e 24h a 33°C, sendo periodicamente avaliados quanto ao, índice de brancura, tensão de ruptura, configuração visual, polimorfismo e comportamento térmico. As misturas entre CBS e MC apresentaram grandes alterações na cristalização e plasticidade à medida que se aumentou o teor de CBS, e o principal efeito desta foi a formação de uma mistura eutética entre as duas gorduras. Já misturas entre CBE e MC são completamente compatíveis e poucas alterações são encontradas para estas misturas mesmo em altas concentrações de CBE. Por isso foi possível utilizar concentrações de até 20% de CBE e 10% de CBS, na produção dos chocolates. Os chocolates armazenados a 20°C apresentaram ótima resistência ao fat bloom e nenhum apresentou sinais da ocorrência deste defeito após 100 dias. Dentre os chocolates submetidos a flutuações de temperatura, após 3 ciclos o chocolate padrão apresentou alterações polimórficas e visuais características de fat bloom que foram intensificadas à medida que os ciclos foram prosseguindo. Os demais chocolates não sofreram influência da variação de temperatura, principalmente o chocolate com CBE que não apresentou nenhuma alteração visual ou estrutural característica de fat bloom, e o com CBS apenas após o sexto ciclo apresentou os primeiros sinais deste fenômeno. Através destes resultados foi possível concluir que apesar da incompatibilidade entre CBS e MC observada pelo estudo da cristalização destas misturas, esta incompatibilidade não foi determinante para acelerar a formação de fat bloom nos chocolates com esta gordura, sendo estes mais resistentes do que o chocolate padrão. A utilização de CBE em chocolates além de não ocasionar alterações de cristalização significativas ainda aumenta a resistência do chocolate ao fat bloom
Abstract: Cocoa butter (CB) is an extremely important natural fat for chocolate formulation, but due to the difficulty access and volatility of its price, alternative fats have been studied and produced to replace them as the Cocoa Butter Equivalent (CBE) and Cocoa Butter Substitutes (CBS). However, the crystallization and sensory characteristics that CB promoted in chocolate are very singular. Moreover, there may be an incompatibility between the alternative fats and CB which will cause defects in chocolate as fat bloom. The aim of this work was study the crystallization of CB, CBE, CBS, and their mixtures, in order to obtain a fraction as similar as possible to the pure CB for the preparation of dark chocolates, and study the influence of these fats on fat bloom formation. The mixtures were prepared based on the total content of CB on chocolate (CB added and CB inside the liquor), and the studied concentrations ranging from 5%, 10%, 15%, 20% and 37.5% of the CBE or CBS on CB. Raw materials and mixtures were characterized by fatty acid composition, triacylglycerol composition, isothermal crystallization, solid fat content, microstructure, thermal behavior, polymorphism, consistency and melting point. To check the effect of the addition of these fats in chocolate quality and resistance to fat bloom, the samples were produced and stored under two conditions, 100 days at 20° C and by temperature cycling for six cycles of 48h, 24h at 20°C and 24h at 33°C, periodically evaluated for, whiteness index, snap, microstructure, polymorphism and thermal behavior. The mixtures between CBS and CB showed large changes in the crystallization and plasticity as the CBS content was increased and the main effect is the formation of an eutectic mixture between the two fats. CBE and CB mixtures are fully compatible and little changes on crystallization of these mixtures are found even at high concentrations of CBE. Therefore it was possible to use 20% of CBE and 10% of CBS in chocolate production. All chocolates stored at 20°C showed excellent resistance to fat bloom and showed no signs occurrence of this defect during the 100 days. Nevertheless, the chocolate standard under temperature cycling, after 3 cycles showed modifications polymorphic and visual characteristics of fat bloom, and these characteristics were enhanced as the cycles were proceeding. Other chocolates were not so influenced by the variation of temperature, especially chocolate with CBE that showed no visual change or structural feature of fat bloom, and with CBS only showed after the sixth cycle the first small signs of this phenomenon. Through these results was concluded that despite the incompatibility between CBS and MC observed in the study of crystallization of these mixtures, this incompatibility was not decisive to accelerate the formation of fat bloom in chocolates with this fat, which are more resistant than standard chocolate. The addition of CBE on chocolates did not result on significant crystallization changes and also increased the resistance of chocolate to fat bloom
Mestrado
Tecnologia de Alimentos
Mestra em Tecnologia de Alimentos
12
Ray, Joydeep. "Production and characterisation of cocoa butter equivalents from high oleic sunflower oil by enzymatic rearrangement". Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/13880.
Testo completoAbstract (sommario):
Cocoa Butter (CB) is one of the most expensive and widely used raw materials in the chocolate and confectionery industries. Due to the rise in the cost of CB in recent years, the variability in quality and the uncertainty in supply, the development of speciality fats with similar triacylglycerol (TAG) compositions to CB with full compatibility has been encouraged. Desirable TAG compositions in a fat can be efficiently achieved via rearrangement of the TAG structure of liquid vegetable oils with selected fatty acids by lipase-catalysed reactions. The main aim of the work presented in this thesis is to produce and formulate different Cocoa Butter Equivalents (CBEs) via enzymatic acidolysis of High Oleic Sunflower Oil (HOSO). This was carried out using a 1,3 regiospecific lipase (Rhizopus oryzae) with 11 different stearic-palmitic acid mixtures at an oil:acid ratio of 1:1.3 (w/w), to produce specialised fats with a high disaturated monounsaturated TAGs (Sat-O-Sat). Diacylglycerols (DAG) were also formed (~7-10%) as a by-product. The TAG and DAG compositions of the acidolysed fat samples were measured using High Resolution Gas Chromatography (HR-GC) and High Performance Liquid Chromatography (HPLC). A probability model was developed which efficiently predicted the final conversions of the major TAGs in the reactions. The variation of TAG composition with time was used to study the reaction kinetics using two different reaction schemes including all possible acidolysis reactions of TAGs with Stearic, Palmitic and Oleic acids at the 1 and 3 TAG positions and as well as reactions involving DAGs with different rate constant assumptions. The later scheme with equal rate constants for equivalent reactions of palmitic and stearic acid produced the best fits for this particular reaction system. Hard stearin fractions with high StOSt content were then isolated from the acidolysed HOSO via removal of free fatty acids by short path distillation (SPD) followed by single stage acetone fractionation. The HOSO hard stearin samples contained varying amounts of StOSt (69-84%) and POSt (4.5-21%), and with overall Sat-O-Sat levels of approximately 90%. This is comparable with commercial Shea stearin which is widely used in CBE formulations. The crystallisation and polymorphic behaviour of the HOSO stearins was studied and compared with Shea stearin. However, the HOSO stearin fractions contained significant amounts of oxidised glycerides (OX) and DAGs particularly of 1,3-StO and so further comparisons were performed on samples which were subjected to an additional silica treatment to remove these minor components. A multi-methodological approach was used for characterization of the samples which included Differential Scanning Calorimetry (DSC) melting, isothermal crystallisation and stop-and-return experiments, X-Ray Diffraction (XRD), pulsed Nuclear Magnetic Resonance (p-NMR), Polarised Light Microscopy (PLM) and Raman microscopy. Four major polymorphs previously found with pure StOSt, α, γ, β', and β were detected in the HOSO stearin and Shea stearin samples. An evidence for a fifth (δ) polymorph was found in DSC experiments, but not via XRD or Raman spectroscopy. The effect of varying StOSt and POSt content in the HOSO stearins was significant, in that crystallisation (at 20°C) speeded up as the StOSt level increased and the POSt level decreased. The main crystallisation event was generally faster for samples with higher StOSt levels (lower POSt levels). The removal of minor components via silica treatment generally speeded transformations to higher polymorphs (γ, β' and β). This was consistent with higher SFC values (similar to Shea stearin). The results suggested that the silica treated HOSO stearins could potentially replace Shea stearin in CBE formulations. CBEs were then formulated by blending the HOSO stearins with Palm oil Mid Fraction (PMF) maintaining a constant StOSt level (~30%) (with varying amounts of POSt and POP). These were compared with CB and standard CBEs (formulated using both untreated and silica treated shea stearins) in terms of composition, crystallisation, polymorphism and compatibility. The CBE blends displayed three major polymorphs, α, β' and β when crystallised isothermally at 20°C or crystallised non-isothermally and remelted. In contrast, transformation to the higher polymorph (β polymorph) was not observed for CB. The main isothermal crystallisation event was generally faster for CBE blends with higher POSt levels (lower POP levels). The CBE blends with higher POP levels as well as trisaturated TAGs tended to transform faster to the β polymorph, though complete transformation was not achieved even after 7 days of storage at 20°C. The overall SFC values of the CBE blends were also generally higher than CB. Mixtures of CBEs with CB (85:15) and Butter fat (BU) (85:15:15) in similar proportions to the fat phase of dark and milk chocolate showed similar crystallisation and melting behaviour to pure CB. Microstructures and XRD patterns of the mixtures of the CBEs with CB and as well as BU, showed evidence of the β polymorph similar to CB after 7 days of storage at 20°C. Iso-solid phase diagrams of mixtures of CBEs with CB in different proportions showed satisfactory compatibility with no eutectic behaviour. Thus the CBEs formulated from the HOSO stearins and PMF can be successfully used to replace CB partially in confectionery applications. Finally, the isothermal crystallisation of CB and selected CBE blends was studied by Hot Stage Microscopy in conjunction with image analysis using a novel image processing algorithm. These were compared with experiments with pure StOSt, POSt and POP and their ternary mixtures. It was possible to visualise and analyse the entire growth history of individual crystals (nucleation and growth kinetics) of these fat samples at different temperatures and polymorphic forms. Nucleation and growth rates of the CB β' crystals were found to vary approximately exponentially with decreasing temperature. The growth of β crystals could be studied by first generating small β crystals using melt mediated transformation from the β' form. These showed constant growth rates. In some cases, the nucleation and growth rates of the Sat-O-Sat crystals were found to increase initially and then decrease with increasing isothermal temperature, due to the impingement effects from the other polymorphs. The Ternary system displayed shorter induction time and faster crystal growth than that of the naturally derived fat samples, presumably due to the absence of other components. The final solid fat content (crystallised fraction) of all the fat samples was found to decrease with increasing temperatures as expected in a fat system.
13
Sirbu, Diana [Verfasser], Nikolai [Akademischer Betreuer] Kuhnert, Nikolai [Gutachter] Kuhnert, Matthias [Gutachter] Ullrich e Frédéric [Gutachter] Depypere. "Comprehensive Analysis of Cocoa Lipidomics – unraveling the unknown chemistry of cocoa butter / Diana Sirbu ; Gutachter: Nikolai Kuhnert, Matthias Ullrich, Frédéric Depypere ; Betreuer: Nikolai Kuhnert". Bremen : IRC-Library, Information Resource Center der Jacobs University Bremen, 2018. http://d-nb.info/1166950743/34.
Testo completo
14
Le, Reverend Benjamin Jean Didier. "Modelling of the phase change kinetics of cocoa butter in chocolate and application to confectionary manufacturing". Thesis, University of Birmingham, 2010. http://etheses.bham.ac.uk//id/eprint/1030/.
Testo completoAbstract (sommario):
Efforts have been devoted over the last decades towards modelling phase change kinetics of fats in chocolate. The fats in chocolate have a number of crystal forms and manufacturers must deliver a product with the right polymorph to the consumer. In this work a simplifed mathematical model was developed that clusters six polymorphs into two, namely stable and unstable, depending on their Differential Scanning Calorimetry (DSC) and X-Ray Diffraction (XRD) characteristics. This simplification allowed the phase change kinetics to be estimated from a set of DSC experiments conducted at different cooling and heating rates. The phase change reactions were coupled with the heat transfer equation and used to model temperature profiles and concentration of polymorphs in a model geometry. The model was able to predict both the temperature profiles measured by thermocouples (\(\pm\)2\(^\circ\)C ) and the fat crystals concentration as measured using XRD (\(\pm\)10%) at various locations in a chocolate slab. The model was applied to the recently developed processes using very high cooling rates such as the FrozenCone process, to explain their capabilities to produce "good" chocolate in spite of the high cooling rates used. Such modelling was not possible with existing models, which usually deal with either heat transfer or isothermal crystallisation kinetics. The main outcomes of this work are (i) the coupling of the reactions kinetics with heat transfer which can be expanded to other processes, (ii) the novel XRD method and (iii) the application to fast cooling processes and their explanation.
15
Miller, Marina Maria. "The effect of applied fields on crystallisation". Thesis, Brunel University, 2000. http://bura.brunel.ac.uk/handle/2438/9216.
Testo completoAbstract (sommario):
The thesis provides a background on crystallisation, the effects of applied fields and summarises the techniques used for characterisation and analysis. The study of applied magnetic fields was carried out on three crystallising systems (a) sucrose, (b) lactose and (c) cocoa butter. Both sucrose and lactose were crystallised from aqueous solutions in incubators at 50°C in applied magnetic fields and the resulting crystals compared to the those obtained under zero field conditions. The results for the sucrose study where the magnetic treatment was carried out under static, dynamic pumped and dynamic syphoned conditions domonstrated that changes in phase, crystallinity, morphology and microcrystallinity were a result of the applied magnetic fields and additional strongly bound water was found to be present within the sucrose crystals most likely to be sucrose hydrates. The resulting sucrose crystals were dependant on the type of field applied, the purity of the sucrose solution and the residence time within the applied field. The lactose study under static conditions provided similar results concluding that applied fields resulted in a more controlled crystallisation resulting in increased crystal size, increased crystallinity and changes in morphology. Crystallisation of cocoa butter from the melt, under normal production conditions in applied fields, resulted in changes in morphology and the time taken to reach optimum tempering which were dependant on the type of applied field and the residence time in the applied field.
16
Wye, Steven Matthew. "Polymorphic transitions in cocoa butter studied by time-resolved small-angle and wide-angle x-ray scattering using synchrotron radiation". Thesis, Keele University, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.590678.
Testo completoAbstract (sommario):
X-ray diffraction is a non-destructive technique which may be used to reveal information about the structure of materials, and is already a widely used tool in the study and determination of the polymorphic nature of cocoa butter and associated triacylglycerols which comprise cocoa butter. Simultaneous wide-angle x-ray scattering (WAXS) and small-angle scattering (SAXS) using synchrotron sources has been carried out on cocoa butter and cocoa butter containing selected additives. Conventional WAXS in a SAXS/\VAXS set up gives information on the cocoa butter atomic distances in the range of 3 - 8 angstroms (A), i.c. packing of cocoa butter chains, and is a familial' and powerful technique in enabling the identification of the polymorphic form of cocoa butter. Whereas SAXS provides information on length scales of 50 - 500 A, i.e. the layout of whole molecules in the form of layers. By using synchrotron sources and the associated high brilliance x-rays, it is possible to study the crystallisation in real-time. Whereas WAXS patterns can take a long time to develop, the associated SAXS patterns evolve before any peaks are observed in the WAXS and are concerned with the onset of crystallisation as well as changes in the pre-crystalline structure and pre-cursors prior to the onset of crystallisation which can determine the final characteristics and properties of the product. Similarly, during melting, the SAXS is the last to survive, in some cases long after the WAXS patterns have disappeared. By recording the SAXS patterns in real-time and using a suitably fast time resolution it is possible to observe the formation of the different polymorphic forms of cocoa butter. As well as transitions between polymorphs via intermediate phases which were observed, including the transition from form I to form III via an intermediate phase, and the formation of form V from the melt phase via an intermediate phase. SAXS studies also provided the ability to study cocoa butter systems containing additives such as sucrose, which itself produces a very strong pattern, making it impossible to identify cocoa butter using the conventional WAXS. It was observed that the addition of sucrose to cocoa butter at the onset resulted in a faster crystallisation rate and a shorter induction time. Other additives were used including silica particles of size 7 and 14 nm which provided a large surface area and also resulted in an increased crystallisation rate and a shorter induction time, seen to depend on surface area. The effect of stearic acid, which is one of the fatty acids present in the many triacylglyccrols of cocoa butter, was also observed in the following two situations: i) stearic acid present and already largely crystallised ii) stearic acid itself crystallising rapidly. It was found that cocoa butter crystallised at higher temperatures with stearic acid present, which promoted nucleation in particular.
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Boock, Kauê Pace. "Desenvolvimento e avaliação da estabilidade fisica de emulsões contendo cristais líquidos e ativos hidratantes à base de manteiga de cupuaçu \'Theobroma grandiflorum\' ou cacau \'Theobroma cacau". Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/60/60137/tde-17092008-092123/.
Testo completoAbstract (sommario):
O desenvolvimento de formulações cosméticas multifuncionais tem sido cada vez mais crescente na indústria cosmética. A elaboração de uma formulação que contém diferentes ativos com propósitos diferentes podendo agir sinergicamente, muitas vezes, confere resultados cosméticos eficazes e até mesmo terapêuticos ao usuário. Nesta pesquisa foram desenvolvidas emulsões cosméticas apresentando formação de fases líquido cristalinas à base de manteiga de cupuaçu (Theobroma grandiflorum), manteiga de cacau (Theobroma cacau), o agente hidratante Hidraskin? e aditivos estabilizantes tais como álcool cetoestearílico, lanolina polietoxilada e carbômero. O desenvolvimento das formulações deu-se pelo método de inversão de fases. Estas foram caracterizadas quanto à formação de mesofases líquido cristalinas e avaliadas quanto à estabilidade física. Foram selecionadas quatro emulsões, duas com manteiga de cupuaçu (com e sem Hidraskin?) e duas com manteiga de cacau (com e sem Hidraskin?) que apresentaram maior estabilidade física e formação de fases líquido-cristalinas mais abundante. A adição do ativo hidratante (Hidraskin?) não alterou as características morfológicas das fases líquido cristalinas, identificadas como fase lamelar e a adição de lanolina polietoxilada como aditivo estabilizante promoveu maior estabilidade fisico-química das emulsões, principalmente quando submetidas à temperaturas em torno de 40ºC também sem alteração das fases líquido cristalinas.Development of multifunctional cosmetic formulations has been growing each day in cosmetic industry. Elaboration of formulations, which presents many actives with different purposes acting together, many times give good and therapeutic results to customers. In this research cosmetic emulsions with liquid crystals were developed based on cupuaçu (Theobroma grandiflorum) or (Theobroma cacau) butter, Hidraskin? as a moisturizer active and actives for stabilization such as cetostearil alcohol, poliethoxilated lanolin and carbomer. Formulations were prepared by the Emulsion Phase Inversion method and characterized on the liquid crystal assembly and evaluated for physical stability. Four emulsions were chosen, two formulated with cupuaçu butter (one with and the other without Hidraskin?) and two with cocoa butter (one with and the other without Hidraskin?), which presented the highest amount of liquid crystals. Addition of Hidraskin? did not change the morphological aspects of liquid crystals, identified as lamellas. Also addition of polyethoxilatted lanolin increased the physical stability of all emulsions prepared, especially when they were submitted to increase of temperature (40ºC).
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Shtay, Rasha [Verfasser], Karin [Akademischer Betreuer] Schwarz e Regina [Gutachter] Scherließ. "Preparation of solid lipid nanoparticles from cocoa butter: Chacaraterization and applications in food sector / Rasha Shtay ; Gutachter: Regina Scherließ ; Betreuer: Karin Schwarz". Kiel : Universitätsbibliothek Kiel, 2017. http://d-nb.info/1233986600/34.
Testo completo
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Miyasaki, Eriksen Koji 1986. "Avaliação da adição de emulsificantes do tipo lecitinas modificadas na cristalização de manteiga de cacau e de chocolate amargo". [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266605.
Testo completoAbstract (sommario):
Orientadores: Theo Guenter Kieckbusch, Valdecir LuccasDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
Made available in DSpace on 2018-08-24T05:00:36Z (GMT). No. of bitstreams: 1 Miyasaki_EriksenKoji_M.pdf: 5704488 bytes, checksum: 8c68d44e4acedc12c047e6f34e53701d (MD5) Previous issue date: 2013
Resumo: As lecitinas modificadas de soja estão sendo introduzidas no processamento de chocolates como alternativa à lecitina padrão para melhorar as propriedades reológicas e de cristalização. A influência da adição de 0,2 a 0,8% (m/m) de lecitinas hidrolisada enzimaticamente, hidroxilada, em pó e acetilada na cristalização da manteiga de cacau foi avaliada. No chocolate, foram adicionadas as lecitinas hidrolisada enzimaticamente e hidroxilada nas concentrações de 0,1 a 0,3% (m/m). Os resultados, para ambos os casos, foram comparados com as amostras contendo lecitina padrão. Para quantificar o efeito destes aditivos foram determinadas as propriedades de fusão e de cristalização por DSC, as características reológicas utilizando um reômetro, a cinética de cristalização usando um Espectrômetro de Ressonância Magnética Nuclear, e o temper index por meio de um temperímetro. Barras de chocolate foram armazenadas a 25°C por 62 dias com o monitoramento dos eventos de fusão por DSC, de textura por texturômetro, das transformações polimórficas por difração de Raios-X e do desenvolvimento de fat bloom por Microscopia Eletrônica de Varredura. A adição de emulsificantes na manteiga de cacau e no chocolate promoveu uma aceleração da cristalização, mas apenas nas concentrações mais baixas. A adição de lecitinas modificadas à manteiga de cacau diminuiu a temperatura máxima de fusão e aumentou a entalpia de cristalização e de fusão. O uso de lecitinas modificadas no chocolate não apresentou vantagens em termos reológicos, se comparadas ao de lecitina padrão. No armazenamento, algumas amostras com lecitinas modificadas foram capazes de retardar a transição polimórfica e a forma VI foi obtida apenas na amostra contendo 0,2% de lecitina padrão. No geral, a transição polimórfica foi antecipada usando maior concentração de lecitina padrão e de lecitina hidrolisada, e retardada com maior quantidade de lecitina hidroxilada. As propriedades de fusão não apresentaram uma tendência definida ao longo do tempo e com a variação de concentração dos emulsificantes. A tensão de ruptura aumentou em chocolates com menores concentrações de lecitinas e uma diminuição significativa desta resistência foi observada a partir de 21 dias de armazenamento nos chocolates com maiores concentrações de emulsificantes. O desenvolvimento do fat bloom não apresentou uma causa única, ocorrendo com e sem transição de fases, e não foi encontrada correlação definida com o tamanho médio de partículas e o índice de temperagem.
Abstract: Modified soy lecithins are being introduced in chocolates processing as an alternative to standard lecithin to improve the rheological characteristics and the crystallization patterns. The influence of the amount added (0.2 to 0.8% (w/w)) and the types of these new additives (hydroxylated, enzymatically hydrolyzed, acetylated, defatted or powder lecithins) on cocoa butter was evaluated. In dark chocolate, enzymatically hydrolyzed and hidroxilated lecithin were added at concentration of 0.1 to 0.3%(w/w) to evaluate mass crystallization. The results in both cases were compared to samples containing standard lecithin. The influence of the addition of lecithins was quantified by determining the melting and crystallization events with a DSC, the rheological characteristics using a rheometer, the crystallization kinetics using a Nuclear Magnetic Resonance Spectrometer, the temper index using a temperimeter. Chocolate bars were stored for 62 days at 25°C, monitoring their melting properties by DSC, texture properties with a texturometer, the polymorphic events by X-rays diffraction and the fat bloom development by Scanning Electron Microscopy. The addition of the emulsifiers to cocoa butter and chocolate accelerated the fat crystallization rates, but only at the lower concentrations. The use of modified lecithins in cocoa butter decreased the maximum melting temperature and increased the crystallization and melting enthalpies. No rheological improvements were detected with the use of modified lecithins in chocolates, compared to the addition of standard lecithin. During the storage period, some chocolates with modified lecithins were able to restrain polymorphic transitions and the polymorphic form VI was only achieved in chocolates containing 0.2 % of standard lecithin. As a general trend, increasing concentrations of standard or hydrolyzed lecithins in dark chocolates anticipate the polymorphic transitions and increasing amount of hydroxylated lecithins delayed these events. No correlation was found between the melting properties with the storage period and with the emulsifier's concentration. Increasing values of mechanical resistance (snap test) were detected in chocolates with the lowest lecithin concentrations and a significant decrease was observed in chocolates with the highest lecithin concentrations after 21 days of storage. The fat bloom development showed no single cause, occurring with and without phase transitions, and there was no clear correlation with the mean particle size and the temper index.
Mestrado
Engenharia de Processos
Mestre em Engenharia Química
20
Oliveira, Glazieli Marangoni 1979. "Influência da adição de hardfats sobre as propriedades tecnológicas do óleo de palma visando a aplicação em chocolates". [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266881.
Testo completoAbstract (sommario):
Orientadores: Theo Guenter Kieckbusch, Ana Paula Badan RibeiroDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
Made available in DSpace on 2018-08-19T03:57:53Z (GMT). No. of bitstreams: 1 Oliveira_GlazieliMarangoni_M.pdf: 37166380 bytes, checksum: d530fd83010bcc0c3c08c7f68ff9ac52 (MD5) Previous issue date: 2011
Resumo: A palma (Elaesis guineensis) e uma das principais fontes de óleos vegetais, sendo o óleo de palma amplamente utilizado na industria de alimentos, como por exemplo, na produção de chocolates. Entretanto, sua utilização para este fim e limitada por seu polimorfismo ß' preferencial, lenta cristalização e formação de grandes aglomerados cristalinos na etapa de pós-processamento. Como alternativa de adequações destas propriedades para aumentar a compatibilidade com a manteiga de cacau, esta pesquisa avaliou a adição de gorduras totalmente hidrogenadas (hardfats) a amostras comerciais de óleo de palma. Os hardfats apresentam composição triacilglicerólica homogênea e bem definida, com triacilgliceróis (TAGs) de alto ponto de fusão, desejável na obtenção de chocolates de boa qualidade. Alem disso, os hardfats podem atuar como moduladores do processo de cristalização, agindo como núcleos preferenciais no processo de ordenação da rede cristalina e como indutores de hábitos polimórficos específicos. O presente trabalho estudou cinco distintos hardfats no óleo de palma, são eles: palmiste (PMTH), palma (PATH), algodão (AGTH), soja (SJTH) e crambe (CRTH). Misturas com 1%, 3% e 5%, de cada hardfat, originaram quinze diferentes combinações de gorduras. Os resultados obtidos por analises de composições de ácidos graxos e triacilgliceróis, assim como as isotermas de cristalização e teor de sólidos obtidos por RMN e, as analises térmicas, realizadas por intermédio de um Calorímetro Diferencial de Varredura (DSC), indicam que o uso de hardfats com cadeias alquilas similares ao do óleo de palma, como PATH e AGTH, proporciona maior compatibilidade na estrutura cristalina e consequentemente melhor empacotamento. A adição de hardfats, que apresentam na composição química, ácidos graxos de cadeias maiores, como a SJTH e CRTH, influenciaram significativamente na aceleração da cristalização do óleo de palma e na redução do tamanho dos cristais, proporcionando maior dureza destas formulações. Todas as misturas mostraram preferência de cristalização de hábitos cristalinos ß', mas as misturas com os SJTH e CRTH, entretanto formaram uma miscelânea de Cristais ß'+ß. A adição destes hardfats provavelmente aumentara a resistência térmica de chocolates. Tomando-se por base este conjunto de resultados, sugere-se a aplicação dos hardfats de algodão e soja, na proporção de 5% e o hardfat de crambe na proporção de 1%, no óleo de palma visando a aplicação em chocolates por meio da substituição parcial da manteiga de cacau
Abstract: Palm threes (Elaesis guineensis) are one of the main sources of industrial vegetable oils. Palm oil, extracted from the pulp of the fruit is widely used in the food industry, as for instance, in the production of chocolates. However, in many applications the amount of palm oil added is restricted by its preferential ß'- polymorphism, slow crystallization rates and formation of large crystalline clusters in the stage of postprocessing. In this research the addition of fully hydrogenated vegetable oils (hardfats) to industrial palm oil samples was evaluated aiming the adjustment of those attributes in order to increase the compatibility with cocoa butter. Hardfats can behave as modulators in the crystallization process and are able to induce specific polymorphic habits due to their homogeneous triacylglicerols profile. Five different hardfats were added to palm oil, in the proportion of 1%, 3% and 5%: palm kernel (FHPKO), palm (FHPO), cottonseed (FFHCO), soybean (FHSO) and crambe (FHCR), rendering fifteen fat mixture formulations. Results obtained through GC analyses for the fatty acids and triacylglycerols profiles, as well as crystallization isotherms and solid fat content by NMR and also thermal analysis using a Differential Scanning Calorimeter (DSC) indicate that the use of hardfats like FHPO and FHCO that have carboxylic chain lengths similar to palm oil implements the compatibility of their mixture with cocoa butter. The addition of hardfats with longer chains like FHSO and FHCR showed significant effect on the increase of the rate of crystallization of palm oil and in the reduction of the crystals size inducing higher hardness to these formulations. All the mixtures showed a preference for the ß'-polymorphism, except for the mixtures with FHSO and FHCR, which produced an assortment of ß'+ ß crystal habits. The addition of these hardfats will probably increase the thermal resistance of chocolates. It is suggested the application of hardfats of cottonseed and soybean in the proportion of 5% and hardfat of crambe in the proportion of 1% in palm oil aiming the application in chocolate by partial substitution of cocoa butter
Mestrado
Engenharia de Processos
Mestre em Engenharia Química
21
Ольшевська, С. С. "Розробка харчових жирів з підвищеною біологічною цінністю". Thesis, Чернігів, 2020. http://ir.stu.cn.ua/123456789/22818.
Testo completoAbstract (sommario):
Ольшевська, С. С. Розробка харчових жирів з підвищеною біологічною цінністю : дипломна робота : 181 – Харчові технології / С. С. Ольшанська ; керівник роботи В. М. Челябієва ; НУ "Чернігівська політехніка", кафедра харчових технологій. – Чернігів, 2020. – 85 с.Розробка харчових жирів з підвищеною біологічною цінністю - це сучасна інновація у сфері харчової промисловості, а використання з цією метою нетрадиційної рослинної сировини – перспективний інноваційний напрям розвитку харчових жирів. Традиційною сировиною для виробництва харчових жирів є саломас та жир-сирець. З метою збагачення харчових жирів необхідними нутрієнтами необхідно розробляти та впроваджувати у масове виробництво рецептури рослиннижирових сумішей з додаванням біологічно активних речовин, що у свою чергу сприятиме удосконаленню асортименту та підвищенню попиту споживачів на вітчизняні рослинно-жирові суміші. Під час виконання випускної кваліфікаційної роботи використані такі методи як: евристичні (органолептичні) та вимірювальні (фізиико-хімічні) методи аналізу. За результатами роботи встановлено, що додавання куркуми та імбиру не впливає на органолептичні та фізико хімічні показники, але уповільнює розвиток МАФАМ, надає продукту привабливого вигляду та визначено, що куркума підвищує терміни зберігання масла вершкового за показником пероксидного числа. Додавання до рослинно-жирових суміші пектину та какао масла не дало значних відхилень від норм стандарту.
Development of edible fats with high biological value is a modern innovation in the food industry, and the use of non-traditional vegetable raw materials for this purpose is a promising innovative direction in the development of edible fats. Salomas and raw fat are traditional raw materials for the production of edible fats. In order to enrich food fats with the necessary nutrients, it is necessary to develop and implement in mass production recipes of vegetable-fat mixtures with the addition of biologically active substances, which in turn will improve the range and increase consumer demand for domestic vegetable-fat mixtures. During the final qualification work such methods were used as: heuristic (organoleptic) and measuring (physico-chemical) methods of analysis. The results showed that the addition of turmeric and ginger does not affect the organoleptic and physicochemical parameters, but slows down the development of MAFAM, gives the product an attractive appearance and determined that turmeric increases the shelf life of butter in terms of peroxide value. The addition of pectin and cocoa butter to the vegetable-fat mixture did not deviate significantly from the standards.
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Juneau, Véronique. "Chronically Elevated Corticosterone Levels, via Cocoa Butter Injections of Corticosterone, Do Not Affect Stress Response, Immune Function, and Body Condition in Free-living Painted Turtles (Chrysemys picta)". Thesis, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/31817.
Testo completoAbstract (sommario):
Chronic stress can result in elevated circulating levels of glucocorticoid hormones in vertebrates, which can affect their stress response, their immune function, and eventually their fitness. I tested the effect of chronic corticosterone (CORT) elevation on the acute stress responsiveness, immune function, and body condition of free-living painted turtles (Chrysemys picta) in Gatineau Park, using slow-release exogenous CORT administration. While Silastic implants did not predictably elevate circulating CORT concentrations in painted turtles, injections of CORT-laden cocoa butter kept circulating levels elevated for up to 3 weeks, to concentrations likely physiologically and ecologically relevant for the species. I measured the acute CORT stress response, parasitaemia, heterophil-to-lymphocyte ratios, and total leukocyte counts after 1 week and 3 weeks, and determined body condition after 1 week, 3 weeks, and 1 year. Compared to sham and control turtles, I observed no effect of treatment on these hormonal, immune, and body condition metrics of stress, possibly because CORT mediates resource allocation only in the presence of additional immune or energy challenges, because of the masking effect of extrinsic factors, or because free, not total, CORT appears to be biologically active.
23
Masuchi, Monise Helen 1985. "Efeito da adição de monoésteres de sorbitana e de estearina da manteiga de cacau como modificadores de cristalização na produção de chocolate". [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266110.
Testo completoAbstract (sommario):
Orientadores: Theo Guenter Kieckbusch, Renato GrimaldiTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
Made available in DSpace on 2018-08-24T21:39:34Z (GMT). No. of bitstreams: 1 Masuchi_MoniseHelen_D.pdf: 6912499 bytes, checksum: 9de5d80a5396749936d252cf9e809a70 (MD5) Previous issue date: 2014
Resumo: O comportamento de cristalização da manteiga de cacau (MC) é um importante parâmetro estrutural no desenvolvimento de chocolates com significativa resistência à formação do fat bloom ¿ um defeito comum em chocolates, caracterizado pela superfície com aparência esbranquiçada e perda de brilho devido à recristalização lipídica local. Com o objetivo de controlar e estabilizar a formação cristalina da MC em chocolates, neste trabalho avaliou-se a influência da adição de monoésteres de sorbitana (monolaurato, monopalmitato, monoestearato e monooleato) e de estearina da manteiga de cacau (obtida por fracionamento da MC com solvente) no comportamento de cristalização e consistência, assim como na microestrutura e no polimorfismo da MC. Monoésteres de sorbitana em três diferentes concentrações (0,5; 1,0 e 1,5% m/m) foram adicionados em MC e seus possíveis efeitos como modificadores de cristalização foram avaliados. O monoestearato de sorbitana (SMS) apresentou-se como o estruturante mais efetivo entre todos os emulsificantes testados, cuja atuação foi atribuída a sua solubilidade em meio orgânico e capacidade de auto-montagem. A adição de 0,5% de SMS em MC promoveu aumento relevante na temperatura de início de cristalização da MC (de 19,3 para 21,6°C) e de 60% na consistência a 10°C, e o típico comportamento de cristalização isotérmica da manteiga de cacau na forma de um plateau foi atenuado. Em paralelo, o fracionamento da manteiga de cacau realizado a 17°C com adição de acetona (MC:solvente = 1:7) produziu uma estearina rica em triacilgliceróis monoinsaturados simétricos, que foi adicionada à MC em três diferentes proporções (95:5, 90:10 e 80:20, m/m) e seus principais atributos físico-químicos determinados. Comparada à MC pura, a mistura 80:20 apresentou aumento de 67% na consistência à 10°C e taxa de cristalização consideravelmente maior. MC contendo 0,5% de SMS e misturas de 80:20 de MC e sua estearina foram usadas na produção de barras de chocolate amargo. As barras foram caracterizadas por avaliação comparativa visual, teste de ruptura, Índice de Brancura, observações por MEV, comportamento de fusão por DSC e polimorfismo por difração de Raios-X. Após o monitoramento sob duas condições de armazenamento - isotermicamente a 20°C e sob ciclos de 24h entre 20 e 32°C - a formação de fat bloom foi significativamente desacelerada em ambas as formulações com uso dos modificadores de cristalização estudados, em comparação com a formulação padrão. A transição polimórfica da Forma V para a Forma VI - que representa o mecanismo mais aceito para a formação do fat bloom em chocolates armazenados sob temperaturas abusivas - pode ser correlacionada com o começo do desenvolvimento do fat bloom superficial
Abstract: The crystallization behavior of cocoa butter (CB) is the crucial structuration issue in the development of chocolate products with significant resistance to fat bloom - a common defect in chocolates, characterized by a whitish appearance and loss of surface gloss due to local lipid re-crystallization. To control and strengthening the crystallization patterns of CB in chocolates processing, in this work it was evaluated the influence of the addition of sorbitan monoesters (monolaurate, monopalmitate, monostearate and monooleate) and cocoa butter stearin (obtained by solvent fractionation of CB) in the crystallization and consistency behaviors as well as on the microstructure and polymorphism of CB. Sorbitan monoesters at three different concentrations (0.5, 1.0 and 1.5% w/w) were added to CB samples and their possible functioning as crystallization modifiers were evaluated. Sorbitan monostearate (SMS) pointed out as the most effective structurant among all emulsifiers tested, a performance attributable to its solubility in organic medium and the ability of self-assembling. Adding 0.5% of SMS to cocoa butter promoted a sharp increase in the onset of the crystallization temperature (from 19.3 to 21.6°C) and a 60% increase in the consistency at 10°C, and the classic two-step isothermal crystallization behavior was smoothed out. In parallel, CB fractionation runs conducted at 17ºC using acetone (CB:solvent = 1:7) produced a symmetric monounsaturated triacylglycerol-rich stearin that were added to cocoa butter at three proportions of CB:stearin (95:5, 90:10 and 80:20, w/w) and main physical-chemical attributes of these mixtures were determined. Compared to pure cocoa butter, the 80:20 mixture showed an increment of 67% in the consistency at 10°C and considerable higher crystallization rates at 17.5°C were found. CB containing 0.5% of SMS and the 80:20 mixture of cocoa butter and cocoa butter stearin were used in dark chocolate bars production. The bars were characterized by visual comparative ratings, snap test, whiteness index, SEM microstructure observations, DSC melting behavior and polymorphism by X-ray diffraction. Storage tests under normal and accelerated conditions confirmed a considerable deceleration in the fat bloom formation rate in samples containing the crystallization crystallization modifiers. The polymorphic transition from Form V to Form VI - which is the most acceptable mechanism for fat bloom formation in chocolates stored under abusive temperature conditions - could be correlated with the onset of surface bloom
Doutorado
Engenharia Química
Doutora em Engenharia Quimica
24
Howard, Brandon Daniel. "Shear and Composition Effects on Porous Network Properties and the Permeability of Lipid Films". The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1593680466745792.
Testo completo
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Quast, Leda Battestin. "Estudo do efeito da adição de gorduras alternativas na cristalização da manteiga de cacau". [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266281.
Testo completoAbstract (sommario):
Orientadores: Theo Guenter Kieckbusch, Valdecir LuccasTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
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Resumo: A influência da incorporação de gorduras alternativas low e zero trans na cristalização da manteiga de cacau foi avaliada através da caracterização física de misturas binárias de manteiga de cacau com gordura de cupuaçu, gordura CBR low trans e gordura CBS, nas proporções de 5, 10, 15, 20, 25 e 30 %. O processo de pré-cristalização (temperagem) foi realizado em um reator encamisado de escala piloto dotado de um agitador e com capacidade para 700 mL. As amostras foram caracterizadas através da curva de sólidos, tensão de ruptura (snap test), calorimetria diferencial de varredura e difração de raios-X. A melhor condição de pré-cristalização da manteiga de cacau pura (taxa de resfriamento de 1,8 ºC/min, cristalização à 24 ºC por um tempo de 8 minutos) também foi utilizada nos ensaios com as misturas, com exceção das amostras com 20, 25 e 30 % de CBR e CBS que foram pré-cristalizadas a 23 ºC por 10 minutos. A manteiga de cacau apresentou um perfil de fusão de gordura na boca, DS(25ºC-35ºC), de 59,2 %, que sofreu apenas pequenas alterações com a adição de até 20 % de cupuaçu e até 30 % de CBR. A curva do conteúdo de sólidos sugere a formação de um eutético entre a manteiga de cacau e a gordura CBS. A tensão de ruptura para a manteiga de cacau foi de 2,48 kgf/cm2 e a adição das gorduras tende a diminuí-la, sendo que com 30 % de cupuaçu e 30 % de CBR esse valor foi 1,90 kgf/cm2 e 1,81 kgf/cm2, respectivamente. Para a amostra com 30 % de CBS a tensão de ruptura baixou para 0,39 kgf/cm2. Observou-se uma diminuição do ponto de fusão das misturas quando comparadas à da manteiga de cacau pura. A difração de raios-X identificou a forma cristalina b como predominante para a manteiga de cacau e para a gordura de cupuaçu enquanto que para as gorduras CBR e CBS a principal forma cristalina é a b'. A incorporação de apenas 10 % das gorduras CBR e CBS à manteiga de cacau promoveu interferências na estruturação cristalina das amostras. O estudo indicou ser possível adicionar até 30 % de gordura de cupuaçu ou CBR e até 10 % de gordura CBS sem alterar de forma sensível os atributos físicos da manteiga de cacau
Abstract: Physical properties of pre-crystallized cocoa butter with the addition of alternative low and zero trans fats were studied. Binary mixtures of cocoa butter were conducted using cupuassu fat, CBR low trans and CBS at 5, 10, 15, 20, 25 and 30 % (w/w) levels. Pre-crystallization was carried out using a lab scale jacket vessel (700 mL) whit stirring system. Samples were evaluated by means of solid fat content, snap test, differential scanning calorimetry and X-Ray diffraction. The better condition for plain cocoa butter pre-crystallization was determined as follows: cooling rate (1,8 ºC/min), crystallization time (8 minutes), crystallization temperature (24 ºC). These conditions were also used for mixtures precrystallization (tempering). Mixtures with 20, 25 and 30 % of CBR and CBS were pre-crystallized at 23 ºC for 10 minutes. Regarding to solid fat content, cocoa butter fusion profile DS(25ºC-35ºC) was 59,2 %. Similar values were obtained for mixtures with up to 30 % of cupuassu and up to 30 % of CBR fats. Mixtures with CBS fat indicated eutectic effect. Snap value for crystallized cocoa butter was 2,48 kgf/cm2. The snap values decreased with the increase of the alternative fats proportion. Mixtures containing cupuassu fat or CBR have similar trend regarding to snap values profile. For mixtures with 30 % of cupuassu and CBR the snap values were 1,90 kgf/cm2 and 1,81 kgf/cm2, respectively. CBS 30% have the lowest snap value (0,39 kgf/cm2). Similar trend was observed regarding to melting point. Alternative fats incorporation decreased the melting point of the mixtures. Regarding to X-Ray diffraction, cocoa butter and cupuassu fat patterns results showed the formation of ß phase. For CBS and CBR patterns, there are evidence of ß¿ phase formation. The addition of 10 % CBR and CBS fat to cocoa butter was detected by X-ray diffraction patterns. The addition of up to 30 % cupuassu or CBR fat, and up to 10 % CBS butter showed no significant differences of physical properties when compared to cocoa butter
Doutorado
Engenharia de Processos
Doutor em Engenharia Química
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Guthrie, Sarah. "Physical Properties of Shear Oriented Cocoa Butter". Thesis, 2008. http://hdl.handle.net/10012/3557.
Testo completoAbstract (sommario):
Cocoa butter is a highly complex system of triacyglycerides which has been shown to crystallize in a markedly different fashion under the application of shear. A rheometer insert was developed to enable the intact extraction of sheared samples for study of melting properties, crystal orientation and breaking stress. Samples were created by ramping from 50°C at three different cooling rates (0.5, 1 and 2°C/min) to three different end point temperatures (16, 18 and 20°C), creating nine different temperature sets. Viscosities of the cocoa butter samples under shear were recorded during sample creation and large jumps in viscosity were identified as form II and form V crystallization. Comparison of crystallization times for the nine different temperature profiles allowed for the conclusion that over a shear range of 90 – 1000 s^-1 there was no further appreciable shear acceleration of the form V transformation for the 16 and 18°C temperatures and only a slight increase up to 500 s^-1 for the 20°C temperature. Sheared samples were also examined with differential scanning calorimetry. Samples were examined for peak melting temperature on each of day 0, day 1, day 7 and day 28. Six of the nine different temperature conditions examined yielded a critical shear rate, above which the melting points of the samples were dramatically different than for low shear and no shear samples. For the day 0 and day 1 samples, above 500 s^-1 the melting temperatures were ~2°C higher than for 360 s-1 and below. For the day 7 and day 28 samples, above 500 s^-1 the peak melting temperatures were ~2°C lower than for the lower shear and no shear samples. The orientation of sheared samples was also examined using x-ray diffraction. In all of the nine temperature sets, orientation was present for shear rates of 360 s^-1 and higher. Breaking stress measurements were performed on sheared and non-sheared samples. These tests showed results remarkably similar to those seen in the DSC tests, with a critical shear rate existing in six of the nine temperature sets, above which an increase in the breaking strength occurs. Examination of samples on either side of the critical shear rate with x-ray diffraction yielded two distinct x-ray patterns leading to speculation that the application of high shear rates causes a change in the crystallization of cocoa butter leading to selective crystallization and the formation of a compositionally different form V crystal with fewer defects than its lower/no shear counterparts.
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Bystrom, Cory. "Evaluation of milk fat fractionation and modification techniques for creating cocoa butter replacers". 1993. http://catalog.hathitrust.org/api/volumes/oclc/32517047.html.
Testo completoAbstract (sommario):
Thesis (M.S.)--University of Wisconsin--Madison, 1993.Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 148-155).
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Wan, Yuen-Ting, e 溫婉婷. "Production of alternative cocoa butter via solvent fractionated and enzymatically modified tilapia viscera oil". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/44755806702144285486.
Testo completoAbstract (sommario):
碩士國立臺灣海洋大學
食品科學系
103
Tilapia viscera are one of the by-products during “Taiwan Tilapia” fillet processing. It contains large amount of palmitic acid and oleic acid which is similar to the fatty acid compositions of cocoa butter. The objective of this research was to produce alternative cocoa butter from refined viscera oil using solvent fractionation and enzymatically modification. The slip melting point of solvent fractionated oil (46.17-54.00℃) was high than cocoa butter (25.67±1.53℃). However, the yield of the fractionated oil was too low because of lacking saturated triglycerides in refined viscera oil, meaning that solvent fractionation is not suitable for producing alternative cocoa butter. Refined viscera oil was converted to cocoa butter replacer by enzymatically modification with 5% lipase, oil: Stearic acid 50 was 1:1.5 at 50℃ for 1 hour. The main fatty acid compositions of cocoa butter replacer were palmitic acid (21.65±1.84%), oleic acid (19.05±1.16), stearic acid (11.20±0.89%) and linoleic acid (10.59±0.70%). The cocoa butter replacer contained 12.06 ± 0.32% 1,3-dipalmitoyl-2-oleoyl glycerol (POP) with melting point 32.43℃ which is similar to melting point of cocoa butter (30.51℃) and without lauric acid. Cocoa butter replacer can replaced 40% (w/w) of cocoa butter in chocolate without affecting the texture.
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Metin, Serpil. "Crystallization behavior and kinetics of blends of cocoa butter and milk fat or milk fat fractions". 1996. http://catalog.hathitrust.org/api/volumes/oclc/37026944.html.
Testo completoAbstract (sommario):
Thesis (Ph. D.)--University of Wisconsin--Madison, 1996.Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 306-319).
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Ransom-Painter, Kelly L. "Incorporation of milk fat, milk fat fractions, and cocoa butter into palm kernel oil based compound coatings". 1995. http://catalog.hathitrust.org/api/volumes/oclc/33182745.html.
Testo completoAbstract (sommario):
Thesis (M.S.)--University of Wisconsin--Madison, 1995.Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 153-165).
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Williams, Sara D. "Phase behavior of mixtures of palm kernel oil with cocoa butter, milk fat and milk fat fractions". 1996. http://catalog.hathitrust.org/api/volumes/oclc/36269266.html.
Testo completoAbstract (sommario):
Thesis (M.S.)--University of Wisconsin--Madison, 1996.Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 209-218).
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Ko, Chi-Hua, e 柯淇鏵. "Thermal Properties and Crystal Growth of Cocoa Butter and Chocolate by Temperature History Method and Melt Crystalllization". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/b977tw.
Testo completoAbstract (sommario):
碩士國立中央大學
化學工程與材料工程學系
107
Cocoa butter is one of the components of chocolate. It is the key factor of affecting the polymorph of chocolate. In this research, we used temperature history method (T-history method) to calculated the thermal properties of cocoa butter and chocolate and compared the polymorph of two samples which made by T-history method. Otherwise, we used the thermal properties which calculated by T-history method to predict the crystal layer thickness of samples of melt crystallization and also analyzed polymorph of two samples. For melt crystallization, we investigate the crystal layer growth versus time curve of samples and compared with the theoretical calculation. We use low temperature differential scanning calorimetry (LT-DSC) to determine the melting point and the equilibrium state and combine with X-ray diffraction to characterize the polymorph of cocoa butter and chocolate. By using T-history method, thermal properties of cocoa butter are: melting point (Tm) = 287.3 ± 0.3 K, heat capacity of liquid state (Cpl) = 3.46 ± 0.34 kJ kg-1 K-1, heat capacity of solid state (Cps) = 7.35 ± 1.47 kJ kg-1 K-1, liquid-solid enthalpy change (ΔHls) = 30.1 ± 1.7 kJ kg-1 K-1, and thermal conductivity (ks) = 0.173 ± 0.07 W m-1 K-1 and the thermal properties of chocolate are: Tm = 290.9 ± 0.3 K, Cpl = 2.92 ± 0.94 kJ kg-1 K-1, Cps=6.39±0.52 kJ kg-1 K-1, ΔHls = 12.3 ± 2.6 kJ kg-1 K-1 and ks = 0.215 ± 0.006 W m-1 K-1. The LT-DSC and X-ray diffraction showed that the cocoa butter and chocolate made by T-history are both form IV and form V, respectively. Melt crystallization showed the crystal layer of samples would increase as time went on. The layer thickness of cocoa butter from melt crystallization was between 0.05 cm and 0.13 cm, and would produce the Form V crystal, which was the most ideal form for chocolate manufacturing. The layer thickness of chocolate made by the same process was between 0.46 cm to 1.27 cm which was ten times larger than cocoa butter. However, it generated the Form II, Form III and Form V crystals. In this research, we investigated the possibility of the application of commercial manufacturing of chocolate without the annealing process.
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Chen, Szu-Lan, e 陳似蘭. "Studies on the Preparation of Raw Materials for Chocolate Making – from Cacao Pod to Cocoa Powder and Butter". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/76033725178268868246.
Testo completo
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Tietz, Russell Allen. "The effects of milk fat minor lipids on the crystallization of milk fat-cocoa butter blends and bloom formation in chocolate". 1998. http://catalog.hathitrust.org/api/volumes/oclc/41933705.html.
Testo completoAbstract (sommario):
Thesis (M.S.)--University of Wisconsin--Madison, 1998.Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 168-174).
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Jovica, Fabiola. "Lipase-catalyzed synthesis of omega-3 vegetable oils". 2010. http://hdl.handle.net/10222/12999.
Testo completoAbstract (sommario):
The effects of temperature, reaction time, and substrate concentration on the incorporation of decanoic acid (DA) and alpha-linolenic acid (ALA), into cocoa butter, were compared, using an immobilized enzyme derived from Rhizomucor miehei. All variables had an effect on incorporation of DA and ALA into cocoa butter but effects were not equivalent for the two fatty acids. Thus, DA was not an adequate model fatty acid for the incorporation of ALA into cocoa butter. The highest ALA incorporation achieved was 77.3±1.3. Samples with ALA incorporated were prepared as “pure” and “blends”, and these exceeded the milk and dark chocolate Canadian Food and Drug Regulation guidelines for products making omega-3 fatty acid content claims. The highest %TAG content, 97.3±1.0%, was achieved for the 11.9wt% “blend” sample. Differential scanning calorimetry suggested that both “pure” and “blend” samples contained mainly form IV and V, with much smaller quantities of form II polymorphs.
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WENG, RUI-GUANG, e 翁瑞光. "Study on hydrogenation of rice bran oil and acetone fractionation of partially hydrogenated rice bran oil for the preparation of cocoa butter substitute". Thesis, 1989. http://ndltd.ncl.edu.tw/handle/64405668195351388307.
Testo completo