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Summary This study investigated the effects of processing and storage on the physicochemical properties and retention of antioxidant compounds of no‐added sucrose chewy candies (NASC) incorporated with differently processed açai (frozen pulp, spray‐dried and freeze‐dried powders). NASC containing freeze‐dried açai had the highest softness and recoveries of total phenolic (TP) and total anthocyanin (TA) immediately after production. Colour parameters and antioxidant capacity by ABTS and ORAC assays had no significant differences after 6 months of NASC storage, except for ORAC in NASC containing spray‐dried açai, whereas DPPH• in all samples significantly increased. Water activity and hardness also increased after storage, whereas TP and TA contents decreased, despite presenting good retentions (approx. 72–78% TP and 84–99% TA). This study suggests that açai has a great potential to be used as a natural pigment and antioxidant source in candy manufacturing, meeting consumption trends towards healthier products.

SummaryThis work aimed to verify the influence of prior homogenization and storage temperature on the crystallization of honey. Honeys from Campos Gerais, PR Brazil, were used for the experiments. The samples were subjected to homogenization at 0, 180, 360 and 540 rpm for 15 minutes and stored at 15 °C or 25 °C. Crystallization was monitored by the colour, absorbance at 660 nm and moisture analysis. At the end of the experiment, the crystal sizes were determined by optical microscopy and laser diffraction. It could be observed that the samples kept at 15 °C and homogenized by agitation at 360 or 540 rpm showed crystal formation after 7 days of storage, while all the samples stored at 25 °C showed crystal formation after 20 days. It was also observed that the effect of temperature was much more pronounced than that of mechanical agitation during homogenization. All the samples stored at 15 °C developed crystals that were smaller than 20 μm.Key words: Size distribution; Crystals; Honey. ResumoO objetivo deste trabalho foi verificar a influência da homogeneização prévia e da temperatura de armazenamento na cristalização do mel. Mel da região dos Campos Gerais/PR (Brasil) foi usado para os experimentos. As amostras foram submetidas a homogeneização sob agitação de 0, 180, 360 ou 540 rpm por 15 minutos e armazenadas a 15 °C ou 25 °C. A cristalização foi monitorada por meio de análises de cor, absorbância a 660 nm e umidade. Ao final dos experimentos, o tamanho dos cristais formados foi determinado por microscopia ótica e difração a laser. Pode-se observar que as amostras mantidas a 15 °C homogeneizadas sob agitação de 360 e 540 rpm apresentaram formação de cristais após 7 dias de armazenamento, enquanto todas as amostras armazenadas a 25 °C formaram cristais após 20 dias de armazenamento. Observou-se que a temperatura teve um efeito mais pronunciado na cristalização do que a agitação durante a etapa de homogeneização. Todas as amostras armazenadas a 15 °C apresentaram cristais menores que 20 μm.Palavras-chave: Distribuição de tamanho; Cristais; Mel.

ResumoO mel é um dos edulcorantes mais antigos utilizados pelo homem, sendo composto principalmente de monossacarídeos, como a glicose e a frutose, responsáveis em parte pela sua cristalização. A cristalização varia segundo diversos fatores, como a concentração de açúcares, o teor de água na sua composição natural, a procedência floral do néctar, o manuseio durante seu processamento, bem como as condições de estocagem. O presente trabalho teve como objetivo avaliar o efeito da temperatura e da incorporação de cristais de mel na cristalização do mel utilizando como parâmetro de acompanhamento a cor, por meio da determinação do Índice de Brancura (IB) e variação da luminosidade (∆L*), e a atividade de água. Utilizou-se um delineamento experimental fatorial 2 2 , tendo-se como variáveis o percentual de cristais de mel adicionado e a temperatura de armazenamento. Apenas as amostras armazenadas à temperatura de 11 e 21 °C cristalizaram, sendo mais evidente a cristalização da amostra armazenada em 11 °C, que foi adicionada de 5% de cristais de mel. O aumento da atividade de água e o aumento no Índice de Brancura (IB), assim como o ∆L*, foram correlacionados com a cristalização das amostras. A maior variação obtida para os valores de ∆L* encontram-se na região de temperatura de armazenamento de 11 °C, na qual as amostras cristalizaram mais rapidamente. Palavras-chave: Mel; Cristalização; Cor; Temperatura; Atividade de água. SummaryHoney is one of the oldest sweeteners used by man, composed mainly of monosaccharides such as glucose and fructose, partially responsible for its crystallization. Honey crystallization depends on several factors, such as the sugar concentrations, natural percentage of water, the floral origin of the nectar, handling during processing and the storage conditions. The present work aimed to evaluate the effect of temperature and of the incorporation of honey crystals on honey crystallization, using the colour (as determined by the Whiteness Index -WI and changes in the brightness -∆L* and the water activity as the parameters to accompany the changes. A 2 2 factorial experimental design was used, the variables being: percentage of honey crystals added and storage temperature. The samples stored at 11 and 21 °C were shown to crystallize, this being more evident in the sample stored at 11 °C with the addition of 5% honey crystals. The increase in water activity and in the Whiteness Index, as well as in the ∆L* were correlated with crystallization of the samples. The luminosity parameter L* and the Whiteness Index (WI) were higher at the temperature of 11 °C, where the samples crystallized faster.

This study examines the inclusion of a quaternary ammonium salt, an alkyl-dimethyl-benzyl ammonium chloride (Dodigen), on a green clay to evaluate its performance as an organophilic adsorbent in the oil/water separation process. The samples were characterized by X-Ray Diffraction, Differential Thermal and Thermogravimetric Analyses, Infrared Spectroscopy, Cation Exchange Capacity, Adsorption Capacity and the Foster Swelling test. The results indicated that the quaternary ammonium salts were intercalated between the layers of clay. A 2 2 -factorial design was conducted with three central points in finite bath tests to determine the rate and capacity of oil removal by the organophilic clays. Values as high as 94.54 % of removal efficiency and 37.57 mg/g of removal capacity were reached in the assays, thus indicating that the use of organophilic clay has great potential in the oil/water separation process.