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.

RESUMENPropiedades físicas de mezclas pre-cristalizadas de manteca de cacao y grasa de cupuassu.Se han determinado las características físicas de mezclas binarias pre-cristalizadas de manteca de cacao (mezcla de Bahia + Indonesia) con 5, 10, 15, 20, 25 y 30 % (m/m) de grasa de cupuassu. La pre-cristalización se ha efectuado a escala de laboratorio utilizando un reactor de vidrio con camisa (700mL) con agitación. Las muestras fueron analizadas mediante calorimetría diferencial de barrido, difracción de rayos-X, contenido en grasa solida y tensión de ruptura. Los valores de tensión de ruptura de las mezclas pre-cristalizadas disminuyeron con la incorporación de grasa de cupuassu, siendo este comportamiento observado también para el punto de fusión. Después de la pre-cristalización, manteca de cacao y grasa de cupuassu confirmaron la presencia de polimorfismo β, por medio de análisis de difracción de rayos-X. La adición de hasta 30% de grasa de cupuassu en la manteca de cacao no afecta de modo significativo en las propiedades físicas cuando son comparadas con la manteca de cacao pura. PALABRAS CLAVE: Atemperado o pre cristalización -Contenido de gordura sólida -Difracción de rayos-X -Grasa de cupuassu -Manteca de cacao -Mezcla binaria de grasas -Tensión de ruptura. SUMMARY Physical properties of pre-crystallized mixtures of cocoa butter and cupuassu fat.The physical characteristics of pre-crystallized binary mixtures of cocoa butter (Bahia + Indonesian blend) and 5, 10, 15, 20, 25 and 30% (w/w) cupuassu fat were determined. Precrystallization was carried out using a lab-scale agitated jacket vessel reactor (700 mL). Samples were submitted to differential scanning calorimetry and X-Ray diffraction. The solid fat content and rupture force were also quantified. The snap values of the crystallized mixture decreased with an increase in the amount of alternative fat. A similar trend was observed with respect to the melting point values. The cocoa butter and cupuassu fat X-ray diffraction patterns confirmed the predominant formation of the β polimorph. The addition of up to 30% cupuassu fat did not significantly affect the values of the physical properties when compared to pure cocoa butter. KEY-WORDS: Binary mixture of fats -Cocoa butterCupuassu fat -Snap test -Solid fat content -Tempering -X-ray diffraction.

Modified soy lecithins are introduced in chocolate processing as an alternative to standard lecithin to improve rheological characteristics and the fat crystallization process. The influence of the type of these additives (hydroxylated, enzymatically hydrolyzed, acetylated, and defatted lecithins) as well as the amount added (0.2, 0.5, 0.8% [w/w]) to cocoa butter was evaluated. The results were compared to samples containing standard lecithin and polyglycerol polyricinoleate (PGPR). The influence of emulsifier addition was investigated measuring the melting and crystallization properties by differential scanning calorimetry (DSC) and the crystallization kinetics using a Nuclear Magnetic Resonance (NMR) spectrometer. The addition of modified lecithins to cocoa butter increased fat crystallization rates, mainly at the lowest concentration evaluated. The isothermal crystallization of the emulsifiers suggests that lecithins may act as co-crystallizers in cocoa butter crystallization. Thus, the acceleration of the crystallization events can be attributed to presence of the high melting point phospholipids and also to solids present in lecithins. Pure PGPR did not crystallize and did not influence the cocoa butter crystallization. The use of modified lecithins in cocoa butter decreased the maximum temperature of melting (T max ) and increased the crystallization (DH c ) and melting (DH m ) enthalpies. Practical application:The modified soy lecithins may be used as alternatives to expand the range of applications of phospholipids containing emulsifiers like standard soybean lecithin. These new commercial emulsifiers may act as crystallization agent, anti-bloom agent, to control polymorphism and as improver of rheological properties of chocolate or the like. Our results showed that the effects of modified lecithins were more prominent than standard lecithin on crystallization process, mainly in low concentration, so that their use can significantly reduce costs in industrial chocolate processing and produce more appealing products.

The consumption of diet products has increased greatly in recent years. The objectives of the study were to develop a bittersweet chocolate added inulin and stevias with different rebaudioside A contents (60%, 80%, and 97%). Five chocolate samples were formulated with different sucrose concentrations to determine the ideal sucrose concentration for bittersweet chocolate. The use of just-about-right scale identified an ideal sucrose concentration of 47.5% (w/w). The sweetness equivalence in sugar-free bittersweet chocolates was determined by the time-intensity method by 14 selected and trained judges. The data collected during each session of sensory evaluation furnished the following parameters in relation to the sweet stimulus: Imax (maximum intensity recorded), Timax (time at which the maximum intensity was recorded), Area (area of time × intensity curve), and Ttot (total duration time of the stimulus). The time-intensity analysis indicated that the percentages of rebaudioside A did not interfere with the sweetness intensity of the sweetener stevia in bittersweet chocolate and there was no significant difference in the concentrations tested (0.16%, 0.22%, 0.27%) of each stevia, in relation to the parameters evaluated. In addition, the reduction in fat content did not alter the perception of the sweetness intensity of the samples. These results showed important information to research and development of chocolate products. Therefore, the use of the lowest stevia concentration tested (0.16%) is the most indicated for use, since this quantity was sufficient to reach the ideal sweetness of the product, so there was no point in adding more.