with the increasing population of the world, and it is necessary to pay attention to increasing. In this project, by adding limon juice, thyme and sour orange juice to coated fish fillets, in order to change the taste of fish, a comparison is made to increase the shelf life in the freezer through the chemical index of total volatile bases, Trimethyl amine, Tiobarbitoric acid and also in refrigerator was performed in terms of total volatile bases.

First, the fish was filleted and washed, then the fish coating mixture was prepared by increasing the extract of limon, sour orange and thyme by 6% of weight to wheat flour, salt and sodium carbonate, and a sample was prepared as a control without extract. Then the prepared mixture was mixed with water in a ratio of 1: 1.5 The fish was immersed in this mixture and remained in this mixture for 5 minutes, then it was kept in the freezer to check the shelf life at -18°C and the quality changes during 6 months were examined and in refrigerator was kept for 7 days and total volatile bases were studied. The amount of volatile bases respectively in the samples containing limons juice, sour orange juice and thyme after 6 months were 21.45, 24.05, 26.75 were lower compared to the control 35.8. Trimethylamine respectively 1.1, 1.25, 1.35 compared to the control 2.5, they had lower values. Thiobarbiotric acid also respectively 0.5, 0.4 and 0.75 were close to or less than the control value. So the shelf life of the products was in limon, sour orange and thyme respectively. at the end section total volatile bases were studied for fish fillets for 7 days and results showed that TVB for control reached to 42 after 7 days and respectively for limon, sour orange and thyme were23.52, 32.5 and 33. So the shelf life of the products was in limon, sour orange and thyme respectively.