Background : Peroxide is the first compound that is produced after fats and oils are oxidated. Whenever peroxide concentration reaches to a certain amount, different changes occur and volatile essences are created which make unfavoured odour and flavour in oils and fats. The present article is a report of evaluation of peroxide concentration in Zoolbia and Bamieh which was planned and applied in kashan city in 2003-2004.

Materials and methods : The research was accomplished by a descriptive study on 57 samples of Bamieh and 36 samples of Zoolbia during 2 years. In this study, firstly, certain amount of sample oil was extracted by Suxeleh method, and then the amount of available peroxide in the oil was measured by titration (Sodium thiosulfate 0.02 Normal). To determine the amount of peroxide, the sodium thiosulfate consumption was measured and calculated by related formula. Statistical analyses were accomplished by use of test.

Results : From total 57 samples of Bamieh, 42 samples (73.7 %) were consumable and 15 samples (26.3 %) were inconsumable. Also 19 samples of total 36 samples Zoolbia samples (52.8 %) were consumable and 17samples (47.2 %) were inconsumable. The maximum peroxide level in Zoolbia and Bamieh samples were 65 and 38.3, respectively.

Conclusions : The results of this study show that most of Zoolbia and Bamieh samples had been inconsumable . According to high amount of peroxide in the most samples and also to dangerous effects that peroxide have on the health it seems that the presentation of continuos planning and practical approaches will be necessary by regional health professional.