جستجوی مقالات مرتبط با کلیدواژه "physicochemical factors" در نشریات گروه "زیست شناسی"

Nowadays, brown macroalgae are considered to be a source of various nutritional and pharmaceutical compounds. In addition, fish roe is very susceptible to spoilage due to its high amount of protein and unsaturated fatty acids. In order to postpone the deterioration of roe-related products, salt and preservatives are utilized. Natural preservatives are recommended because of the adverse effects of chemical additives. Thus, different concentrations of pure alginate (0.1%, 0.2%, 0.3%, 0.4%, 0.5%) were chose and then the 0.2% alginate was selected on the basis of the sensory evaluation of the results. Moreover, the treatments including control (salt-alginate-free), A1 (containing 2.5% salt) A2 (containing 0.2% alginate), A3 (containing 2.5% salt and 0.2% alginate) were used to investigate their preservative effects on fish roe. The quality of rainbow trout roe was assessed within 0, 15, 30, 45 days at refrigerated storage. The treatment A3 showed significant differences in microbial, chemical and sensory results compared with other treatments (p≤0.05). According to the results, salting 2.5% and alginate 0.2% method gave good flavor and increased shelf life to the roe.

In order to investigation of water quality of the Choghakhor wetland by use of WQI, ten stations were selected. Sampling was done every 45 days since April 2010 until March 2011 with 3 replications at each station. Water Quality Index (WQI) was calculated using nine water quality parameters (Nitrate, Nitrite, Alkalinity, Hardness, Turbidity, Conductivity, Dissolved Oxygen, pH and Biochemical Oxygen Demand). For this propose, the relative weight assigned to each parameter ranged from 1 to 4 based on the importance of these parameters for aquatic life and their role in use of water resource for human life. The results of analyses of variance (ANOVA) showed a significant difference between different stages (p