تاثير استفاده از كلينوپتيلوليت (زئوليت) بر مجموع ازت هاي فرار (TVN) آرد ماهي كليكا در طول نگهداري

Effect of using clinoptilolite (Zeolite) on total vlatile nitrogen (TVN) of Kilka fish meal

Fish meal is the best source of animal protein in aquatics nutrition. Because fish meal contains many nutritive compounds, it may be spoiled more than other sources. Some methods using additives were employed to keep its quality. This study was conducted to investigate the clinoptilolite (zeolite) effects as an additive on total volatile nitrogen (TVN) of Kilka fish meal in summer 2008. Four types of treatments which included fish meals containing 2, 4 and 6 percent clinoptilolite and control (fish meal without clinoptilolite) with 6 replicates per treatment were used in this experiment. Clinoptilolite was heated and mixed exactly with Kilka fish meal, and then they were stored in tight plastic bags. Total volatile nitrogen was measured by AOAC (2000) method immediately after it was mixed and this process was repeated 4, 6, 8, 10 and 12 weeks after combination respectively. The data were analyzed by MSTATC (version 1) statistics package and one-way (CRD) ANOVA method, and averages were compared by Duncanʹs test. The results showed that different levels of clinoptilolite (zeolite) decreased TVN of Kilka fish meals significantly (P<0.05). The minimum and maximum amount of TVN were observed in treatment consisting of Kilka fish meal ehich was mixed 4 percent clinoptilolite and control treatment respectively (54.83 vs 76.53 mg/l00g).