Determination of polycyclic aromatic hydrocarbons (PAHs) in water, sediment and tissues of five sturgeon species in the southern Caspian Sea coastal regions

Concentration levels of 16 polycyclic aromatic hydrocarbons (PAHs) consisting of naphthalene, acenaphthylene, acenaphthene, fluorine, phenantherene, anthracene, fluoranthene, pyrene, benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenzo(a,h)anthracene, indeno(1,2,3-cd) pyrene and benzo(g,h,i)perylene were measured in water and sediment samples collected from the southern Caspian Sea coasts at four stations of Noshahr, Freydoonkenar, Sari and Amirabad during autumn, winter and spring of 2005-2006. Also, tissue samples from five sturgeon species including stellate sturgeon, Persian sturgeon, beluga, Russian sturgeon and ship sturgeon were obtained. Samples were analyzed by gas chromatography after the extraction process and the obtained data were statistically analyzed using One-Way ANOVA analysis at confidence level 95%. The mean concentrations of PAHs in water and sediment samples were 0.004-2.946 mgl-1 and 0.024- 2.336 µg g-1, respectively. No significant difference was found in the mean concentrations of PAHs among stations and seasons of the examined samples. Also, mean concentration of PAHs in the liver, muscles,gills, kidney and gonads of five sturgeon species was 0.81-1.34 µgg-1. The results of this study show that the levels of PAHs in water, sediment and sturgeon organs were below the acceptable levels of PAHs proposed by USEPA and WHO

Impacts of whey protein edible coating on chemical and microbial factors of gutted kilka during frozen storage

The aim of the present study was to investigate the impact of whey protein coating on quality and shelf life of Kilka fish. Whey protein edible coating was prepared in three different concentrations, including 3, 7, 10 and 13%. Then gutted Kilkas were coated for 1h, packed in polyethylene dishes with cellophane blanket and stored at -18 °C. Total microbial count, total volatile nitrogen (TVN) and moisture evaluation were carried out within 0, 1, 2, 3 and 4 months (sample size: 75 packages, weighted 250 grams each). Results showed that there was no significant difference between total microbial count and total volatile nitrogen among samples (p>0.05). Moisture of coated samples with 13% concentration of whey protein had significant difference with other treatments (p<0.05) suggesting that whey protein edible coating with 13% concentrations can enhance quality and increase shelf life of Kilka fish in storage of freezing up to 4 months

Effect of whey protein coating on physico-chemical properties of gutted Kilka during frozen storage

The a im of th is paper was to study the effects w hey pro t e in c oat i ng on ch e m ic al a nd physic al properties of gut t ed K i l ka dur i ng f roz en stor a ge. Coating of Kilka has done by dipping in whey protein solution with different concentrations of 3, 7, 10 and 13%, for 1h. Then, after being packed in polyethylene dishes, they were covered in cellophane blanket and stored in -18°C. There were 125 testing and control packages, each of them weight 250grams. Heme iron, peroxide value, protein, lipid and pH has measured after 0, 1, 2, 3 and 4 months storage in freezer. R e s u l ts of h e me iron, p e roxi de v a l ue and lipid of control tr e at m ents h a ve s hown s i gni f icant difference among ex p e r i m ent al tr e at m ents (p0.05). Our results showed that coating process with di ff e r e nt whey pro t e in con c entrat i on leads to decrease in peroxide value and increases the iron content. 13% whey protein concentration was provided the most satisfactory results

Effects of different concentrations of sodium alginate as an edible film on chemical changes of dressed kilka during frozen storage

The aim of this study was to investigate the effects of sodium alginate edible coating with concentrations of 0/25, 1/25, 0/75 and 1/75% (W/V) on chemical changes of dressed Kilka during frozen storage. Prepared samples of Kilka fish have been coated for 1 h with the dipping method. Coated and uncoated samples have been packed in polyethylene dishes with selphon coverage (75 packs of 250 g). Chemical parameters (moisture, ash, protein, TVN and lipid) were examined in frozen storage at -18ºC for 4 months. SPSS Statistical Software was used for data analysis, using One Way ANOVA test. Significant reduction was found (P<0.05) in moisture value with increase of sodium alginate concentration during the study. Significant differences were found in TVN values during the third and fourth months but there were no significant differences (P<0.05) in ash and protein content. The highest content of TVN was found in control samples and use of sodium alginate edible coating affected the reduction of TVN, prevented the lipid oxidation, increased the shelf-life of Kilka and reduced the moisture