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Considering the need to understand the fluid rheology, the aim of this paper was to study the rheological behavior of the following plant-based beverages: plant-based beverage made of Brazil nut and Baru (EHCBB) and nut-based beverage made of Brazil nut and Macadamia (EHCBM).

RESUMOO uso da radiação ultravioleta é um dos vários processos físicos que podem ser utilizados para a esterilização ou na higienização de superfícies que irão entrar em contato com alimentos. Objetivou-se, nesta pesquisa a avaliação da eficiência da radiação ultravioleta (UV) na esterilização de superfícies de embalagens para alimentos visando a redução da contaminação microbiológica. Tampas e filmes plásticos foram irradiados em uma fonte de ultravioleta emitindo comprimentos de ondas a 254 nm, no interior de uma câmara especialmente projetada para este estudo, através de um delineamento fatorial para testar as variáveis: tempo de exposição e intensidade de irradiação (distância da fonte). Avaliou-se o número de reduções decimais de esporos de Bacillus subtilis inoculados na superfície das embalagens. As reduções decimais obtidas não foram altas, variaram de 0,21 a 2,47, mas o uso da lâmpada UV foi altamente eficiente para tempo de exposição superior a 30 s e distância mínima de 20 cm da fonte, causando a redução total da carga microbiana inoculada. Termos para indexação:Radiação UV, esterilização, embalagens plásticas. ABSTRACTUltraviolet radiation is one of the major physical processes used to sterilize or to clean surfaces that will be in contact of foods. This research evaluated the efficiency of ultraviolet (UV) radiation to sterilize surfaces of plastic packaging materials based on the reduction of microbial counts. Plastic closures and films were irradiated by exposing them to lamps emitting UV radiation at 254 nm in an apparatus specially constructed for this study. Using an experimental design in order to investigate the effect of exposure time and distance from the source, the reduction number of Bacillus subtilis spores inoculated to the package surfaces were evaluated. The UV radiation efficiency was not high for short exposition time, presenting reduction number ranged from 0.21 to 2.47, but it was very efficient when exposed to more than 30 s at a distance of 20 cm.

a b s t r a c tThe sporicidal effect of hydrogen peroxide (H 2 O 2 ) in the sterilization of low density polyethylene film (LDPE) was evaluated using a Central Composite Design (CCD). The effects of contact time (5-19s), bath temperature (23e70 C) and concentration of H 2 O 2 (0e35%) in an immersion bath were investigated.A 16 cm 2 film surface was evenly inoculated with 100 mL of the test microorganism Bacillus subtilis var.globigii ATCC9372 spores. The effective H 2 O 2 sporicidal activity was demonstrated at concentrations from 18 to 35% and in a temperature range from 46 to 70 C, resulting in 2e7 decimal reductions of B. subtilis spores. A quadratic mathematical model representative of the action of H 2 O 2 on the B. subtilis spores was developed as a function of concentration, time and temperature. Test specimens sanitized with 28% H 2 O 2 at 60 C for 8 s showed 4 decimal reductions. In the same sterilization procedure, but extending the time to 16 s, this value increased to 7 decimal reductions, demonstrating the efficiency of H 2 O 2 as a function of contact time. The sterilization system tested showed satisfactory performance in the sterilization of LDPE films, being capable of reaching up to 7 decimal reductions of the bacterial spore population.

The aim of this work was to obtain Brazil-soluble Brazil nut extract on a pilot scale, to determine the physical-chemical, microbiological, sensory and rheological characteristics of the products obtained and to determine the microbiological, physical-chemical and physical stability of the extract in presence and absence light and preservatives. This is a quantitative study, carried out in the laboratory. Extracts were characterized in terms of physicochemical (proximate composition, mineral profile, pH, titratable acidity, color), rheological (apparent viscosity, flow index, consistency coefficient), microbiological (yeast and molds, Salmonella sp., coliforms at 35ºC and at 45ºC and coagulase positive Staphylococcus), and sensory (odor, color, taste, global impression, buying intention) parameters. Furthermore, the effect of the addition of preservatives (500 mg/L citric acid, 0.15% w:v sodium benzoate and 0.1% w:v potassium sorbate) and of the exposure to light on the physicochemical (pH, titratable acidity), physical (color variation) and microbiological stabilities throughout storage were assessed. The extracts had high energy content, due to its high protein and fat contents, besides being a valuable source of selenium. The extracts were characterized as non-Newtonian pseudoplastic fluids, and were well accepted in sensory analysis, with up to 60% of the consumers indicating willingness to buy the product. The presence of preservatives at least doubled the shelf-life of the products, from 9 to up to 21 days. The incidence of light had no effect in the stability of the extracts.

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De acordo com a legislação brasileira, chá pronto para consumo é a bebida obtida pela maceração, infusão ou percolação de folhas e brotos de várias espécies do gênero "Thea" (Thea sinensis e outras) ou de folhas, hastes, pecíolos e pedúnculos de erva-mate da espécie "llex paraguariensis" ou, ainda, de outros vegetais previstos nos padrões de identidade e qualidade. Admite-se, também, que outras substâncias de origem vegetal e açúcares sejam adicionados (BRASIL, 1997).Para ser considerada uma bebida de baixa caloria, o chá deve atender a algumas exigências, quanto ao teor de calorias e açúcares. Deve ser uma bebida não-alcoólica e hipocalórica e ter o conteúdo de açúcares normalmente adicionado na bebida convencional substituído por edulcorantes hipocalóricos ou não-calóricos, sejam eles naturais ou artificiais (BRASIL, 1999).Existem diversos trabalhos na literatura referentes a chá preto adoçado com diferentes edulcorantes. Cardello (2001) estudou a aceitação de chá preto em pó solúvel adoçado com aspartame, estévia e ciclamato/sacarina e sacarose por indivíduos que praticaram exercício físico antes de consumir o chá. Cardoso e Cardello (2003) avaliaram amostras adoçadas com aspartame, ciclamato/sacarina, estévia e sucralose através de terminologia descritiva, utilizando o Método de Rede -Kelly's Repertory Grid Method (MOSKOWITZ, 1983). Cardoso, Battochio e Cardello (2004) determinaram a equivalência de doçura e poder edulcorante de adoçantes em função da temperatura de consumo de bebidas preparadas com chá-mate em pó solúvel.Os objetivos deste trabalho foram: i) aplicar a Análise Descritiva Quantitativa para traçar o perfil sensorial de três amostras comerciais de chá gelado light sabor pêssego, adoçados AbstractIn this work, three different brands of light peach iced tea (A, B and C), purchased in a local market and packed in PET bottles were sensory analyzed. At first, Quantitative Descriptive Analysis (QDA) was conducted in order to obtain the sensorial profile, with eleven tasters, previously selected and trained. The product acceptance was evaluated by 33 consumers, representing the target public. The QDA results were submitted to ANOVA, Tukey's test and Principal Component Analysis (PCA). The sample A was mainly characterized by banana aroma and flavor; the sample B by artificial peach aroma and refreshment; while the sample C by sweetness and natural peach aroma. The acceptance test, analyzed by ANOVA and Tukey's test, showed a greater acceptance for the sample C. The colour of the samples was evaluated by the Cielab L*a*b* method and the sample C stood out by the red colour. Keywords: light tea; peach; sensory analysis; quantitative descriptive analysis; acceptance test. ResumoNo presente estudo foi determinado o perfil sensorial e a aceitação de três marcas comerciais de chá light sabor pêssego, denominadas A, B e C, acondicionadas em embalagem PET e adquiridas no comércio local. O perfil sensorial foi determinado por Análise Descritiva Quantitativa (ADQ) utilizando-se uma equipe de 11 provadores rigor...

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