Structuration of lipid bases zero-trans and palm oil-free for food applications.

This work evaluated structured lipids (SLs) through chemical and enzymatic interesterification (CSLs and ESLs). Blends of soybean oil and peanut oil 1:1 wt% were used, with gradual addition of fully hydrogenated crambe to obtain a final behenic acid concentration of 6, 12, 18, and 24 %. Chemical catalysis used sodium methoxide (0.4 wt%) at 100 °C for 30 min, while enzymatic catalysis used Lipozyme TL IM (5 wt%) at 60 °C for 6 h. Major fatty acids identified were C16:0, C18:0, and C22:0. It was observed that with gradual increase of hard fat, the CSLs showed high concentrations of reaction intermediates, indicating further a steric hindrance, unlike ESLs. Increased hard fat also altered crystallization profile and triacylglycerols composition and ESLs showed lower solid fat, unlike CSLs. Both methods effectively produced SLs as an alternative to trans and palm fats, view to potential future applications in food products.

The influence of conching time on the sensory profile and consumer acceptance of milk chocolates enriched with freeze-dried blueberry (Vaccinium spp.).

Conching is a processing stage of industrial chocolate manufacture that is essential to the development of the sensory and rheological properties of the finished product. It promotes the physicochemical changes leading to flavor, aroma, and flowability refinement by continuously heating, aerating, shearing, and homogenizing chocolate mass during an extended time length. Conching duration is a key processing parameter that depends on the type of chocolate, the quality of primary ingredients, the conche's configuration, and the desired sensory outcome in the chocolate. Shorter cycles are often beneficial to manufacturers, due to increased productivity and reduced energy consumption, but they may be insufficient to fully develop chocolate's desired sensory properties. The present study aimed to shed light on the trade-off between product quality and process efficiency by assessing if varying conching durations were associated with statistically significant differences in the sensory profile and consumer acceptance of milk chocolates with freeze-dried blueberry. Samples were produced under an alternative method of conching prior to ball mill refining, with times investigated being 6, 12, 24, 36, 48, and 72 h, and were subsequently submitted to Quantitative Descriptive Analysis and consumer acceptance test. No statistically significant differences in either sensory profiles or consumer acceptance ratings of samples were observed, with the exception of hedonic values for aroma, indicating that a 6-h conching cycle was already enough to develop the sensory properties of the milk chocolate with freeze-dried blueberry. The feasibility of shorter conching times suggests a potential for energy saving and increased productivity in the production of milk chocolates following the conching prior to ball mill refining concept.

Sensory Profile and Consumer Acceptability of Prebiotic White Chocolate with Sucrose Substitutes and the Addition of Goji Berry (Lycium barbarum).

Functional food is a product containing nutrients that provide health benefits beyond basic nutrition. The objective of the present study was to evaluate the descriptive sensory profile and consumers' acceptance of functional (prebiotic) white chocolates with and without the addition of an antioxidant source (goji berry [GB]) and sucrose replacement. The descriptive sensory profile was determined by quantitative descriptive analysis (QDA) with trained assessors (n = 12), and the acceptance test was performed with 120 consumers. The correlation of descriptive and hedonic data was determined by partial least squares (PLS). The results of QDA indicated that GB reduces the perception of most aroma and flavor attributes, and enhances the bitter taste, bitter aftertaste, astringency, and most of the texture attributes. The consumers' acceptance of the chocolates was positive for all sensory characteristics, with acceptance scores above 6 on a 9-point scale. According to the PLS regression analysis, the descriptors cream color and cocoa butter flavor contributed positively to the acceptance of functional white chocolates. Therefore, prebiotic white chocolate with or without the addition of GB is innovative and can attract consumers, due to its functional properties, being a promising alternative for the food industry.

The Influence of the Rebaudioside A Content of Stevia (Stevia rebaudiana Bertoni) on the Determination of Sweetness Equivalence in Bittersweet Chocolates, Using the Time-Intensity Analysis.

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.

Influência da adição de lecitina de soja e do poliglicerol poliricinolato nas propriedades reológicas do chocolate / Influence of addition of soy lecithin and polyglycerol poliricinolato the rheological properties chocolate

O objetivo deste trabalho foi avaliar o comportamento reológico de chocolate do tipo meio-amargo, variando-se os teores de lecitina e poliglicerol poliricinolato (PGPR). As amostras de chocolate foram preparadas adicionando-se de 0,3 a 1,4% (m/m) de lecitina e a combinação de lecitina/PGPR com PGPR constante de 0,2% e variando-se o teor de lecitina em 0,3, 0,5 e 0,8%. As análises reológicas foram realizadas nas temperaturas de 40ºC (início da temperagem) e de 31ºC (final da temperagem). No início da temperagem, até o percentual de 0,5% de lecitina houve redução na viscosidade plástica e aparente. O limite de escoamento apresentou aumento após a adição de 0,5% de lecitina. Para as amostras contendo lecitina e PGPR, o comportamento das curvas de viscosidade e o limite de escoamento foi semelhante ao das amostras contendo apenas a lecitina. A adição de diferentes teores de emulsificantes não interferiu nos parâmetros da temperagem.

Estudo cinético da secagem de banana-prata em secador de leito fluidizado e ajuste de modelos matemáticos aos dados experimentais / Kinetical study of \"prata\" banana drying in a fluidized-bed dryer and adjustment of the mathematical models to the experimental data

Estudou-se a cinéticade secagem de banana-prata em um processo à alta temperatura e curto tempo (HTST) em secador de leitofluidizado. As curvas de secagem foram levantadas nas temperaturas de 100C, 130C e 150C e os dados obtidos foram correlacinados com diversos modelos matamáticos existentes na literatura. Bons resultados foram obtidos com o modelo de Page e o modelo das Duas Resistências de Brunello. As umidades de equilíbrio foram obtidas pro meio de GAB (Guggenhein-Anderson-de Boer) que apresentou melhor ajuste à isoterma de sorçäo da fruta, levantada experimentalmente à temperatura de 25C.

Determinaçäo experimental do calor específico e densidade real de chocolate tipo cobertura / Experimental determination of the specific heat and true desnity of coating chocolate

O calor específico (Cp) e a densidade real(p)de chocolate tipo cobertura (ao leite, amargo e branco) foram determinados experimentalmente para três marcas comerciais de chocolate. O calor específico foi obtido utilizando-se um calorímetro de mistura e as medidas foram realizadas em duas faixas distintas de temperaturas de 25C a 50C. Os resultados experimentais de calor específico foram comparados com valores calculados por meio de modelos matemáticos já existentes em litaratura em funçäo das composiçöes químicas do chocolate, as quais foram previamente determinadas através de análises físico-químicas. Os valores de densidade real encontrados para diferentes tipos e marcas comerciais de chocolate apresentavam poucas variaçöes entre sí, tanto na fase líquida e os valores médios obtidos foram de 1,3g/cm3 e 1,2g/cm3 para amostras a 25 e 50C, respectivamente. Houve uma variaçäo significativa de calor específico, indicando uma dependência com a composiçäo química dos chocolates. Os valores médios de Cp encontrados foram de 0,290cal/(gC) e 0,334cal/(gC) para faixas de 5 e 20 a 60C, respectivamente. Os valores encontrados a partir da correlaçäo de OKOS foram substancialmente maiores do que os valores experimentais.

Determinaçäo experimental da difusividade térmica de chocolate tipo cobertura / Experimental determinationof thermal diffusivity of chocolate for coverings

A difusividade térmica de chocolate tipo cobertura foi determinada experimentalmente utiluzando-se um tubo de difusividade, conforme proposto por DICKERSON (1965) e os valores de condutividade térmica determinados indiretamente. Para a faixa de temperaturas de 5 a 25C foram encontrados valores de difusividade térmica de 1,9795x-7m2/s e condutividade térmica de 0,0495 cal/m.sC para chocolate amargo, 1,7905x10m2 e 0,0461 cal/m.sC pra o chocolate ao leite e 1,2905x10-7m2/s e 1,2905x10-7m2m/s e 0,450 cal/m.sC para o chocolate branco. Já a faixa de temperatura de 40 a 60C os valores de difusividade térmica e condutividade térmica foram de 1,4007x10-7m2/s e 0,1261 cal/m.sC para chocolate amarg, 1,4516x10-7m2e e 0,1240cal/m.sC pra chocolate ao leite e 1m3532x10-7m2/s e 0,1037cal/msc para chocolate branco. A etapa de teperagem teve uma leve influência na condutividade térmica do chocolate amargo. Os valores encontrados foram de 0,0869 cal/m.sC e 0,1053 cal/m.sC para chocolate temperado e näo temperado, respectivamente. O valor da difusividade térmica para chocolate amargo, obtido pelas correlaçöes de OKOS (1986), foi bastante diferente do obtido experimentalmente.

Propriedades reológicas de chocolates comerciais tipo cobertura / Rheological properties of chocolate coverings

As propriedades reológicas da massa de chocolate säo influênciadas por fatores como conteúdo de matéria graxa, umidade, presença de lectine e outros emulsificantes, tempo de conchagem, grau de temperagem, tamanho de partículas, temperatura entre outros. Alguns destes fatores estäo relacionados com a própria composiçäo do chocolate e outros referem-se a diferenças no processo de fabricaçäo. O chocolate é uma suspensäo de partículas näo-gordurosas, como açúcar e sólidos de cacau, em uma fase gordurosa contínua de manteiga de cacau, sendo caracterizado reologicamente como um fluído pseudoplástico. Através do modelo proposto por Casson, uma regressäo linear com os dados de tensäo de cisalhamento e taxa de deformaçäo fornece parâmetros limite de escoamento de Casson (tca) e viscosidade plástica de Casson (tca). O equipamento utilizado para as medidas experimentais foi um reômetro rotativo de cilindros concêntricos. Os resultados reológicos foram analisados e discutidos em funçäo da composiçäo química e física dos chocolates estudados.