عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Paste of big head carp fish was prepared based on three formulas and was selected base on organoleptic properties test results. The product was then divided into three portions of: sample 1 (control), sample 2 (containing 0.01% Butylated Hydroxy Anisole BHA antioxidant) and sample 3 (containing 0.02% antioxidant BHA). To determine the shelf life, the samples were frozen and kept in cold storage of -18 ?C. During the certain time intervals of 0, 15, 30, 60 and 90 days microbial tests were performed, and peroxide value Total Volatile Nitrogen (T.V.N), and fatty acids profile determined. TVN of the control sample reached from 11.2 to 25.48 mg/100g respectively at zero time and after 60 days of being kept in cold storage. As for the sample containing antioxidant BHA of 0.01% concentration, the content of TVN reached 25.9 mg/100g after a lapse of 90 days. In the sample containing antioxidant BHA of 0.02% concentration, TVN content reached 25.34 mg/100g after 90 days. Therefore, based upon TVN as the most important index to determine the paste's shelf life, and compared with the shelf life of the control sample, the samples containing BHA with concentrations of 0.01 and 0.02 percent acquired shelflives of 60 and 90 days respectively. Change in peroxide value in the control sample equaled to 0.9 (meq of O2/kg) in zero time. It reached 1.4 meq of O2/kg after 15 days, and 0.5 meq of O2/kg after 30 days, but it reached 0 meq of O2/kg after being kept for 60 days in cold storage -18 ?C. Peroxide value in the sample containing BHA with the concentration of 0.01% reached 2.6 meq of O2/kg and in the sample containing BHA with the concentration of 0.02 percent reached 2.2 meqO2/kg after 90 days. During the 90 days of being kept in cold storage, the saturated fatty acids increased slowly in both control and the sample containing 0.02 percent BHA; the mono unsaturated fatty acids decreased while the poly unsaturated fatty acids increased. Omega-6 fatty acids increased swiftly, while the omega-3 fatty acids did so slowly. All the results from the statistics point of view are significant at (p?0.05) level.