Investigation on the Changes in Color Parameters and Turbidity of Cornelian Cherry (cornus mass L) Produced by Microwave and Conventional Heating

Background and Objectives: Red colored fruits such as cornelian cherry (Cornus mas L) are recognized as being healthy. The color of these fruits is an important sensory property in assessment of product quality therefore, minimizing the loss of color in the process is very important. Materials and Methods: In this study, comparison of the color, turbidity, degradation rate of anthocyanin, and rate of evaporation in cornelian cherry (cornus mass L) juice produced from microwave and conventional heating at different operational pressures (12, 38.5 and 100 K Pa) was investigated. Results: The final brix juice 42  was obtained in 137, 125, and 93 min by conventional heating at 100, 38.5 and 12 K Pa, respectively. Applying microwave energy decreased the required times to 115, 90 and 75 min at 100, 38.5 and 12 K Pa, respectively. In both methods, the heating temperature at pressures of 12, 38 and 100 K Pa was 50, 75 and 100 ° C, respectively. The results also showed that hunter lab values (L, a, and b) were decreased with increasing the time of process, turbidity, and degradation rate of anthocyanin. Conclusions: The heating method affects the color, degradation rate of anthocyanins and evaporation rate of cornelian cherry concentrate. Also the results indicated that temperature and time of process are higher in conventional heating than in microwave. Degradation of anthocyanins and color of cornelian cherry juice was more evident in rotary evaporation as compared to microwave heating method. Thus according to the results, microwave energy could be successfully used in production of cornelian cherry juice concentrate.