Protein and lipid changes of FPC produced from Caspian Sea kilkas in VP and MAP during storage at different temperatures

Fish Protein Concentrate (FPC) is a healthy, sustainable and high nutritive product that produced from fish and protein and other nutrients are more concentrated than in the fresh fish. The aim of this research is to study the sustainability of FPC produced from Kilka (combination of three Caspian Sea Kilka species, Clupeonella engrauliformis, C. grimmi and C. cultriventris which were not identified and processed separately) in VP (Vacuum Packaging) and MAP (Modified Atmosphere Packaging) at different temperatures during six months of storage. According to result of chemical analysis performed, protein content was evaluated 91.2%, lipid 0.5%, ash 3.6%, moisture 2.3%, TVN 10 mg/100g and peroxide 5 meq/kg in the produced FPC before packing. Amino acids and fatty acids were also determined. Lipid amount in FPC after 6 months at 35°C in VP changed from 0.50 to 0.45 and in MAP (combined of 60% CO2, 30% N2 and 10% O2), decreased from 0.50 to 0.36. It was also detected that increase in temperature leads to more decrease in lipid content but it was not significant (P>0.05). Protein content of FPC has changed from 91.2% to 73.6% during six months at 35°C in VP and 69.4% in MAP. But at 5°C, protein contents were changed from 91.2% to 88.4% and 81.2% in VP and MAP, respectively; these changes were significant (P<0.05) but the decrease in MAP was again more than VP

Determination of nutrient values of the bivalve Anodonta cygnea in Selkeh area of the Anzali Lagoon during autumn and spring

Anzali Lagoon is one of the most important aquatic ecosystems of Iran which was registered as a Ramsar Convention site in 1999. This valuable ecosystem is located in the south west shores of the Caspian Sea, in Guilan Province. We randomly collected 30 and 20 samples of the bivalve Anodonta cygnea in autumn 2004 and spring 2005 respectively. The Selkeh area was chosen for the sampling because of its availability during autumn. The area receives water from the southern part of the lagoon basin. Nutrient content of the soft tissue of the bivalve was measured. Live sampled bivalves were transferred to laboratory and their length, width, height; total body weight and wet weight of the internal soft part were measured. Moisture, ash, protein, T.V.N, lipid and amino acid contents in soft tissue were also determined. Moisture content in spring and autumn samples were 84.84% and 83.6%, respectively. Ash content in autumn samples was higher than spring samples, being 4% and 2.32%, respectively. Assessment showed protein content in the autumn samples to be 12% while in spring samples this was 10.5%. T.V.N content in autumn and spring samples were 0.031 and 0.003% respectively. Measurements showed that autumn bivalves had 4% lipid content whereas this value in spring samples was 3%. We found Sixtheen amino acids, including seven essential ones in the samples

The effect of different methods on fatty acid composition of Tilapia, Oreochromis niloticus, fillets

Tilapia, a perch fish from Cichlidae family has witnessed a vast and fast growth in artificial culture due to simple and inexpensive procedures for the practice. One of the most important farm species is considered to be the Nile Tilapia (Oreochromis niloticus). The effects of different cooking methods on fatty acid composition and nutritional value of Tilapia fish fillet were evaluated. The cooking methods included: Red off, microwave, oven cooking, barbecue, boiled water and raw treatment. The protein content was assessed using the Kjeldahl method, moisture was evaluated through dry method, fat and ash through Soxhlet and electric furnace methods. To measure the composition of fatty acids, Gas-chromatography method (GC) was applied, and the Bligh and Dyer method of extraction and identification of fatty acids was implemented. The results showed that applying different curing methods caused moisture loss of 1-9%, 2-12% increase in protein content, fat reduction of 0.2-4.2% (excluding the red off treatment in which fat increased by about 0.5%), increase in ash of 0.7-0.15%, reduction of Mono Unsaturated Fatty Acids between 1-6% and increase in Poly Unsaturated Fatty Acids between 0.5-14%. The rate of saturated fatty acids showed an increase of 0.6-1.6% in all treatments with the exception of baking and red off treatments. The results indicated the lowest change (about 0.2%) in EPA, in the microwave and grilled fillet treatments and the highest change (0.7%) in the red off fillets compared to raw samples. The minimum change in DHA was observed in the oven-cooked fillets (0.45%) and the maximum change (2.5%) in the red off fillets. The highest EPA and DHA were found as 1.33 and 3.32% in samples cooked in oven. Results showed that the ratio of 6/ 3 increased in the red off samples compared to other treatments

Comparison of qualitative characteristics of fish paste produced from minced kilka (Clupeonella cultriventris) and silver carp (Hypophthalmichthys molitrix)

The aim of this study was to determine the qualitative characteristics of ready-made fish paste made from minced meat (Clupeonella cultriventris) and silver carp (Hypophthalmichthys molitrix) and its shelf-life at a refrigerated temperature.This compilation was performed in five treatments including amounts 100, 75, 50 and 25 percent of processed fish meat were cured. The treatments were packed in heat-resistant glass after pasteurization. Samples were stored at 4oC for 40 days.The amount of TVB-N in the experimental treatments during the course of the change was increased that this factor varied between15.25-31.25 mg/100 g of meat in experimental treatments. This factor was in the 100% rolled silver carp treatment until the end of the shelf life in the standard range. The amount of tybarbibacteric acid increased during storage period varied between 0.13- 2.11mg malondialdehyde/1000g in experimental treatments, but this factor was in the 100% treatment of silver carp paste after the end of the maintenance period in the standard range (less than 1.8 mg/100gr), in other treatments, after 30 days, was more than standard limitation. The pH changes in treatments did not significantly decrease (P>0.05), this factor varied between 5.05 to 5.93 in the experimental period. Total bacterial counts, psychrophilic bacteria and coliform and molds were not observed in experimental treatments during storage period. Microbial contamination was not observed during the storage period in the refrigerator in the experimental treatments. The taste and texture in silver carp treatment (100%) were better than other treatments. The ash, protein and fat in 5 treatments did not significantly change during storage (p>0.05). The moisture content was not significantly increased in all five treatments during storage (p>0.05). Results showed treatment of processed carp (100%) was better than other treatments (p<0.05)