Mohammad Vahedi Torshizi; Mohsen Azadbakht; Mahdi Kashaninejad
Abstract
Given that color is one of the appearance characteristics of food products for customer selection and marketability, in this study, an ohmic heating system had made in three input voltage gradients (8.33, 10.83, 13.33 V/cm) and three percent weight loss (10, 20 and 30%) of the total weight in the heating ...
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Given that color is one of the appearance characteristics of food products for customer selection and marketability, in this study, an ohmic heating system had made in three input voltage gradients (8.33, 10.83, 13.33 V/cm) and three percent weight loss (10, 20 and 30%) of the total weight in the heating process. After the heating process, the color change was analyzed using Image J software and the factors L *, a *, b *, BI, C, TCD were measured and the results were analyzed using the response surface method. The results showed that for L *, b *, browning index, chroma index and TCD had the highest estimation coefficient for weight loss percentage and for a * value of process voltage had the highest estimation coefficient. Also, except for the factor a *, where the quadratic model is suitable for the two model factors, for the other factors, the linear model is obtained against the mean of the appropriate model by the response surface. In the analysis of response surface diagrams, the L * and a * factor had the highest value in the voltage range of 50 to 65 volts and the weight loss percentage of 20%, and for b *, the browning index and TCD had the highest values at voltages of 70 and above and a weight loss of 25%.
