Nectars are formulated beverages with a fruit juice or pulp as its main component. A blend of fruits can also be used, with the advantage of combining sensory and nutritional properties of different fruits. The beverages may be added with some energetic component, as caffeine, known by its stimulating effect on central nervous system. The objective of this study was to develop mixed nectar of cashew apple, papaya, guava, acerola fruit and passion fruit added caffeine. The beverage was prepared with 35% juice blend and 10% sugar, added with 100 mg of caffeine L )1 and 60 mg of sodium metabisulfite (SO 2 ) L )1 and 500 mg of sodium benzoate L )1 as preservatives, packed in cleaned pasteurised bottles and heat processed at 90°C for 30 s. Physicochemical, microbiological and sensory analyses of the beverage were performed initially (time zero) and during 6 months of storage at room temperature (about 25°C). The products were microbiologically stable during storage. The vitamin C content decreased significantly throughout storage time, although it has remained relatively high. The product presented good sensory acceptance, which suggests its potential for market.

Resumo: Países tropicais, como o Brasil, são depositários de uma grande variedade de fontes de polissacarídeos vegetais conhecidos e outros ainda não explorados que possuem grande potencial em aplicações industriais. Alguns estudos reportam a possibilidade de aplicação industrial da goma exsudada do cajueiro em substituição à goma arábica devido à semelhança estrutural e química. Neste estudo propôs-se caracterizar comparativamente algumas propriedades destas duas gomas, antes e após dois tratamentos de extrusão termoplástica. Nos resultados de composição centesimal as amostras de goma de cajueiro in natura e processadas destacaram-se pelo alto teor de fibra solúvel. Por outro lado, apresentaram menor teor de minerais que a goma arábica. Por meio da análise de viscosidade rápida, foi observado que este parâmetro aumentou nas amostras de goma arábica processadas, enquanto nas amostras processadas de goma de cajueiro houve redução. Nos resultados da análise de difração de raios X predominou-se a conformação amorfa das cadeias poliméricas de ambas as amostras. A partir dos parâmetros avaliados, a goma de cajueiro poderia ser indicada como substituta da goma arábica. Palavras-chave: Goma de cajueiro, goma arábica, extrusão. Cashew Gum (Anacardium occidentale): Evaluation of Chemical and Physical Changes by Thermoplastic ExtrusionAbstract: Tropical countries such as Brazil are rich in a great variety of plant sources of polysaccharides, some of which are not known or explored yet and could have great potential in industrial applications. Some studies report the possible industrial application of cashew gum as substitute for Arabic gum owing to their structural similarity. This study aimed at comparing properties of these gums before and after two treatments of thermoplastic extrusion. The cashew gum raw and processed was found to possess high content of soluble fibers and low ash content, also exhibiting a lower content of minerals in comparison with Arabic gum. The rapid viscosity increased upon processing for Arabic gum, while it decreased for cashew gum. With x-ray diffraction we confirmed the amorphous conformation of the polymer chains of both samples. From the parameters evaluated, we conclude that cashew gum could be used as a replacement for Arabic gum.

The purpose of this work was to develop energy drinks from mixed tropical fruit nectars with added caffeine or guarana. The nectars were formulated from puree blends, consisting of cashew apple, acerola, papaya, passion fruit and guava. Firstly, a mixture design was carried out by varying the puree proportions, in order to establish the most accepted formulation of the mixed nectar. Higher proportions of guava and papaya purees resulted in better acceptance scores, while passion fruit puree impaired the product acceptance. The most accepted formulation was that with the following puree contents: passion fruit, 3.9%; papaya, 5.7%; guava, 5.7%; and acerola, 5.7%. This formulation was defined as the control for the difference-from-control sensory tests, conducted to compare the control added with energy components (guarana or caffeine) with the control itself. Although both energy drinks were significantly different from the control, they were well accepted, indicating their potential for being commercialised.

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Bacterial cellulose (BC), which is usually produced as pure membranes (sheets) by some bacteria, has been widely studied as a nanomaterial with unique properties for a variety of applications, but it has been actually used mostly for biomedical applications. There are many potential food applications that have not been adequately explored, nata de coco being virtually the only food product from BC on the market. Food applications have usually been considered as less economically feasible, but several studies had demonstrated the suitability of cost-effective fermentation media for producing BC, widening its scope of applications. BC may be used in foods as intact membranes impregnated with other components, or after disintegration or hydrolysis to produce bacterial cellulose nanofibrils or nanocrystals. Abrief overview of actual and potential applications of bacterial cellulose in food industry is presented.