Production of Fig Juice Concentrate from Dried Fig Fruits (Sabz cultivar) and Evaluation of Color Changes

Fig juice was concentrated by various heating methods. Dried figs were soaked in water with three different temperatures and finally filtered. The final juice concentration of 65 ºBrix was achieved by heating in 10، 25 and 63 min using microwave، rotary vacuum and atmospheric heating processes، respectively. The color changes during concentration processes were investigated. Total color differences، Hunter L*، a* and b* parameters were used to estimate the extent of color loss. L* and b* parameters decreased with time but a* and total color difference increased. It was observed that the severity of color loss was lower in microwave heating process than the others. Different types of kinetic models were also applied to the changes in color parameters. The combined model fitted very well with all parameters.