The polymorphic phases of natural fat extracted from cupuassu beans were studied by performing in situ temperature-dependent X-ray scattering experiments and differential scanning calorimetry (DSC) using synchrotron radiation. Cupuassu (Theobroma grandiflorum) is a native plant of the Theobroma species originally found in Brazil's Amazon region, with a great potential for utilization in the chocolate industry. The experiments and data analysis were performed using as a reference the known polymorphic phase behavior of cocoa butter. The results led to the identification of cupuassu fat polymorphic crystalline phases. Using the nomenclature generally found in the literature for triaceylclycerols (TAGs) systems, these phases were labeled γ, R, β 0 , and β in increasing order of melting temperature and stability. Differential scanning calorimetry measurements of fusion temperatures indicated the existence of two β states in cupuassu fat. These phases were labeled β 2 and β 1 , following the aforementioned nomenclature. In spite of the different melting points, the existence of a β 2 f β 1 transition could not be proven, due to the great deal of structural similarity of the corresponding X-ray patterns obtained in our experiments. A comparison of our results with those reported for several pure compounds and ternary mixtures of TAGs indicated that these components are mainly responsible for the cupuassu fat phase behavior. This study provided the first experimental results of an in-situ follow-up of the polymorphic phase transitions and crystallization of fat from Brazilian cupuassu beans, an industrially important natural product.

Summary Physical characteristics of precrystallised binary mixtures of cocoa butter (CB) and 5, 10, 15, 20, 25 and 30% (w/w) cocoa butter replacer (CBR) or cocoa butter substitute (CBS) were determined. The lipid composition was obtained by chromatography and the solid fat content (SFC) by nuclear magnetic resonance. Tempering was carried out using a lab‐scale agitated jacket vessel reactor. Bars made with tempered samples were submitted to X‐ray diffraction and rupture tests. Snap values of crystallised mixtures decrease with an increase in the amount of alternative fat. X‐ray diffraction patterns confirmed the predominant formation of the beta polymorph habit for CB and beta prime form for CBR and CBS. Mixtures of CB and CBR exhibit chemical compatibility. The knowledge of the snap values and of the variation of SFC with temperature proved to suffice to adequately anticipate the influence of the addition of alternative fats on chocolates physical attributes.

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Análises térmicas da gordura de cupuaçu natural (Theobroma grandiflorum Schumann) proveniente de Manaus, AM, realizadas com um Calorímetro Diferencial de Varredura (DSC), indicaram um comportamento polimórftco semelhante ao da manteiga de cacau. Quando submetidas ao processo de temperagem tradicional utilizado para a manteiga de cacau, ambas as gorduras mostraram preferência de cristalização nasFormas rv e V. As composições em ácidos graxos e triglicerideos, obtidas por cromatografia, assim como a curva de sólidos da gordura de cupuaçu, obtida em RMN, sugerem o uso de frações específicas da mesma, misturadas com frações do óleo de palma, para a obtenção de gorduras alternativas à manteiga de cacau (CBA's) com boas características de fusão, para uso na fabricação de chocolate e/ou produtos análogos.Gordura de cupuaçu natural foi neutralizada e submetida a um processo de fracionamento térmico a seco em um reator de cristalização, com capacidade para 3 fitros.Aplicou-se um Planejamento Fatorial (3 1 x 2 1 }, com a temperatura de cristalização variando em três níveis (26, 28 e 30°C} e a velocidade de agitação variando em dois níveis (10 e 20 rpm), envolvendo seis tratamentos com repetição, totatizando 12 ensaios.A fração estearina com propriedades mais adequadas foi a E30/20, obtida na temperatura de cristalização de 300C e com uma rotação do agitador de 20 rpm, com tempo total de fracionamento de 11 horas e 15 minutos. Misturas de E30/20 com uma fração média de palma desodorizada conduziram a três gorduras, classificáveis como Gorduras Equivalentes à Manteiga de Cacau (CBE's), segundo os critérios analíticos estabetedctos pela União Européia (UE}. Foram desenvolvidas 18 formulações de chocolate (ao leite, amargo e branco), variando-se a composição da fase gordurosa através da substituição de 16% da manteiga de cacau pelas gorduras alternativas, e 6 formulações padrões de chocolate, utilizando-se manteiga de cacau pura. Os resultados das avaliações físicas, químicas e sensoriais dos chocolates demonstraram não haver diferenças entre os chocolates produzidos com e sem o uso das CBA's.Palavras-chave: cupuaçu, Theobroma grandiflorum, chocolate, fracionamento térmico, polimorfismo, gorduras alternativas à manteiga de cacau, CBA, CBE.

Due to the attack of cacao (Theobroma cacao L.) plants by the fungus Moniliophthora perniciosa which caused witches' broom disease in the state of Bahia, Brazil, resistant clonal material with elevated productivity and superior physical characteristics has been selected for use in the genetic improvement program and by the cocoa producers themselves. The present study aimed to characterize the cocoa butter and chocolates produced from nine cacao varieties and also from the Amelonado cacao produced in the same region (denominated as Common), with a view to quality improvement. The cocoa butter was characterized for its solid fat content and triacylglycerol composition, and the chocolates for their moisture and protein contents, maximum particle diameter, pH value, acidity, rheological properties and instrumental texture, as well as a sensory test for acceptability with 50 consumers. A relationship was found between the triacylglycerol composition and solid fat curves of the cocoa butters and the instrumental texture of the chocolates, the highest values for the latter parameter being observed for the varieties with greater amounts of symmetrical triacylglycerols and greater solid fat contents at the temperatures evaluated. From a sensory point of view, it was shown that overall acceptance and buying intention were mainly determined by the attributes of ''astringency,'' ''bitterness,'' ''acidity'' and ''chocolate flavor.'' It was also shown that chocolates produced from varieties descendent from the Trinitario group were differentiated from those descendent from the Forastero group, showing the preference of consumers for these materials and the possibility of a gain in quality in the genetic improvement of cacao by including varieties descended from the Trinitario and Criollo groups in the crossing programs, associating disease resistance with product quality.