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"Cajuina" is a very popular drink in the Brazilian northeastern region and is produced by clarifying cashew apple juice. To preserve "cajuina" from chancing, the clarified cashew apple juice is submitted to thermal treatment where a desired final color should be obtained. To optimize color formation while maintaining high vitamin C and low 5-hydroxymethylfurfural (5-HMF) concentrations the thermal treatment of "cajuina" needs to be studied and the non enzymatic mechanism should be better understood and controlled. In this work the effect of thermal treatment on "cajuina" (clarified cashew apple juice) was studied at temperatures from 88°C to 121°C. Changes in color were measured and the variation in vitamin C, 5-hydroxymethylfurfural (5-HMF) and sugar content were used to evaluate non enzymatic browning. The kinetic models were used to optimize the thermal treatment to produce "cajuina" with an absorbance at 420 nm of 0.023

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Production of lactic acid by hydrothermal conversion of glycerol is an option to add value to the large amounts of glycerol that is being generated during the production of biodiesel. This work aimed to separate lactic acid by ion-exchange resins in a fixed-bed column. Adsorption isotherms were obtained from the breakthrough curves using different initial concentrations of lactic acid (60-302 g/l) and temperatures (30, 40 and 60 °C). Maximum adsorption capacities were estimated by the Langmuir model. Adsorption and desorption cycles for a binary and a real mixture were performed. The methodology proposed for the separation of lactic acid in a fixed-bed column presented high values of adsorptive capacity for both Amberlite IRA-96 and Amberlite IRA-67 resins at 30 °C. Lactic acid was more strongly adsorbed by Amberlite IRA-96 than the IRA-67 resin with maximum adsorption capacity of 544 and 341 g/l, respectively. Chromatographic experiments for the singlecomponent solution (lactic acid), binary mixture (lactic acid and glycerol) and real mixture showed high values of recovery (29.2%, 31.3% and 23.5%, respectively) and productivity (3.14, 7.00 and 2.43 kg of lactic acid/kg resin. day).

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A simple method of quantification of liquid distribution efficiency was employed to characterize a packed column (diameter, 0.4 m; height, 1.8 m), on a pilot scale, operated with 1-in. plastic Pall rings. Two distribution efficiency factorsglobal and dispersionwere defined from a normal tridimensional surface. The global efficiency is derived from the amplitude, and the dispersion efficiency, from the distribution variance. Two series of tests were run. In the first series, just one pipe was employed to feed the column. In the second series, the tests were run with a pipe lateral distributor representative of commercial application. Without the packing, the distance between the distributor and the column base was varied. The greatest dispersion efficiency values from the first series were smaller than the smallest values from the second series, which showed that the packing per se does not promote good distribution. The efficiency values showed that the smaller the distance between the distributor and the packing surface, the better the initial distribution is.

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