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The kinetics of anthocyanin degradation in blueberry juice during thermal treatment at 40, 50, 60, 70, and 80 degrees C were investigated in the present study. Anthocyanin degradation was analyzed up to the level of 50% retention using a pH differential method. The degradation of anthocyanin at each temperature level followed a first-order kinetic model, and the values of half-life time (t(1/2)) at temperatures of 40, 50, 60, 70, and 80 degrees C were found to be 180.5, 42.3, 25.3, 8.6, and 5.1 h, respectively. The activation energy value of the degradation of the 8.9 degrees Brix blueberry juice during heating was 80.4 kJ.mol(-1). The thermodynamic functions of activation (DeltaG, DeltaH, and DeltaS) have been determined as central to understanding blueberry degradation.

a b s t r a c tOsmotic dehydration of banana (Musa sapientum, shum.) was optimized with respect to temperature (25e55 C), salt (0e10 g/100 g) and sucrose (30e60 g/100 g) concentrations through response surface methodology. The solution of Fick's law for unsteady-state mass transfer in a cylindrical configuration was used to calculate the effective diffusivities of water, sucrose and NaCl. Analyses were conducted in triplicate for moisture, sugar and salt contents. Peleg's model was used to predict the equilibrium condition, which was shown to be appropriate for water loss and solute uptake. For the above conditions of osmotic dehydration, the effective diffusivity of water was found to be in the range of 5.19e6.47 Â 10 À10 m 2 s À1 , the sucrose effective diffusivity between 4.27e6.01 Â 10 À10 m 2 s À1 and that of NaCl between 4.32e5.42 Â 10 À10 m 2 s À1 . The working conditions that simultaneously optimize these 3 variables were the temperature of 25 C with a solution composed of 30 g/100 g of sucrose and 10 g/100 g of sodium chloride. This condition provided values of 4.80 Â 10 À10 m 2 s À1 for effective diffusivity of water, of 3.21 Â 10 À10 m 2 s À1 for effective diffusivity of sucrose and 4.49 Â 10 À10 m 2 s À1 for effective diffusivity of sodium chloride.

The aim of this study was to develop and compare the properties of edible films based on pinhão starch and pinhão flour. Seven formulations were developed by casting methodology: 5% pinhão starch with 0, 1, 1.5, and 2% glycerol, and 5% pinhão flour with 1, 1.5, and 2% glycerol. The films were evaluated and compared to each other for thickness, morphological analysis by Scanning Electronic Microscopy (SEM), glass transition temperature (T g), apparent porosity (Ø), water vapor permeability (WVP), tensile properties, color, opacity, and Fourier transform infrared analysis (FTIR). In

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