Because the find more heat transfer occurs essentially by conduction and convection, conventional thermal technologies are not homogeneous, causing the product in direct contact with the hot surfaces to overheat. Therefore, the preservation of the quality and the nutritional parameters of heat-treated fruit represents a major challenge for the traditional processing techniques for fruit pulp and other products. Innovative technologies have been widely research as alternatives to traditional thermal processing.

Among these technologies are high pressure processing (Rawson, Brunton, & Tuohy, 2012; Verbeyst, Crombruggen, Van der Plancken, Hendrickx, & Van Loey, 2011), pulsed electric fields (Charles-Rodríguez, Nevárez-Moorillón, Zhang, & Ortega-Rivas, 2007; Plaza et al., 2011) and ohmic heating. Ohmic heating (OH) appear as

a solution to reduce thermal damage because it heats materials in a rapid and homogeneous manner. This technique may allow improved retention of vitamins, pigments and nutrients because this type of heating is rapid and uniform, resulting in less thermal damage to labile substances (Castro, Teixeira, Salengke, Sastry, & Vicente, 2003, 2004; Eliot-Godéreaux, Zuber, & Goullieux, 2001; Ruan, Ye, Chen, Doona, & Taub, 2002; Sarang, Sastry, & Knipe, 2008). Ohmic heating, also known as electroconductive heating, can be defined as a process in which foods LGK-974 price are heated by passing alternating electrical current (AC) through them. Most food products contain ionic constituents, such as salts and acids, that enable the conduction of electrical current (Palaniappan & Sastry, 1991). This process can be used to generate heat within the product, transforming electrical energy into thermal energy and

thus heating materials at exceptionally rapid rates without the need for a heating medium or surface (Sastry & Barach, 2000). Among ohmic heating applications in the food industry are blanching, evaporation, dehydration, pasteurization and extraction (FDA, 2000). The aim of this study was to analyze the effect of ohmic heating on blueberry pulp anthocyanins Celecoxib by applying a rotatable central composite design to identify the optimal processing conditions. A two-variable full factorial central composite and star design was employed to evaluate the influence of the applied voltage and the solids content (SC) on the level of anthocyanin degradation. Finally, the ohmic heating process was compared with conventional heating. Southern Brazil cultivars of highbush blueberries (Vaccinium corymbosum) were used in these experiments. The samples were purchased from Italbraz Company (Vacaria, Brazil) and kept at −18 °C until analysis. The blueberry pulp used in this study was prepared by grinding the fruits and diluting the resulting material to adjust the total solids content to five different values between 4 and 16 g/100 g. To prevent precipitation, 1 g/100 g xanthan gum (Hexus Foods, Portão, Brazil) was added to the mixture.