Fruits are natural sources of vitamins, minerals, carbohydrates and other nutrients. Tropical fruits are consumed and appreciated all over the world due to the taste and flavour. This work aims to evaluate the physicochemical composition of fermented pineapple beverages, study associated fermentation kinetics and optimize fermentation conditions through the use of multiple linear regression and surface response analysis. Pineapple juice was characterized physiochemically using measures of soluble solids (brix), acidity, density and pH. It was determined that a fermentation temperature of 25 °C, pH between 3.0 and 4.0, and inoculum quantity of 4–5 g·L-1 resulted in a high-quality fermented beverage with 8.1% (v/v) ethanol content. A kinetic study was performed on the alcoholic fermentation process, monitoring the following variables: Brix, acidity, density, and alcohol content. The results showed that higher concentrations of yeast results in higher productivity and was possible to optimize the processes to maximize the results. This process is technically viable and can yield a value-added product that can generate revenue as well as other significant economic benefits for the beverage market.

Corrosion of buried pipelines is a matter of concern to the oil and gas industry since the time when carbon steel began to be widely used in these pipelines for the transportation of fluids. The microbial communities associated with biofilms promote modification in the surrounding environment and may accentuate the degradation of oil and gas pipelines causing leaks or even accidents. This work aimed to evaluate corrosion and biofilm formation in carbon steel API 5LX60 coupons buried in clayey soil from an industrial region in northeastern Brazil. The average corrosion rates were determined by gravimetric test and the quantification of bacteria and fungi were using the Most Probable Number (MPN) and Colony Forming Units (CFU) techniques respectively. The results showed a great influence of clayey soil on corrosion rates and time of adherence for microorganisms on metal surfaces.

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Aluminum oxide and titanium oxide are widely used as catalytic support. Due to their characteristics and properties, they have several applications such as chemical processes, photocatalysis and pollution control. In this work, the catalytic supports of Al 2 O 3 and TiO 2 were impregnated with 2% of copper oxide by the method of impregnation. The catalysts were characterized by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Brunauer-Emmett-Telle (BET) surface area and Infrared Spectroscopy techniques (FTIR). The results of XRD analysis presented the Cu/TiO 2 catalyst with high degree of crystallinity where the peaks corresponding to the phases anatase, rutile and CuO are easily found, while the Cu/Al 2 O 3 catalyst presented low degree of crystallinity. The samples morphology is in the form of agglomeration, the specific surface area was higher when copper metal was impregnated to the supports and the highest values was obtained with Cu/Al 2 O 3 catalyst. FTIR analysis allowed the visualization of the main vibrations of the functional groups presents in the catalysts samples. According to the results, it was observed that the incorporation of copper oxide did not affect significantly the crystalline structure of TiO 2 and Al 2 O 3 and that at the calcination temperature of 500°C it is possible to obtain a high specific surface area and a more active phase resulting in a good characterization which is suitable for various industrial applications.