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In this study, for the first time in Iran, the effect of edible coating of sodium alginate and whey protein in combination with innclulated cultivation of Pediococcus acidilactici and Lactobacillus plantarum bacteria on rainbow trout fillets was studied. Accordingly, chemical indicators such as pH, TVB-N, TBA and microbial laod at 0, 7, 14 and 21 days of refrigeration storage at 4C were investigated. Results showed that in all samples pH, TVB-N and TBA increased over time. In terms of microbial parameters, probiotic coating could reduce the number of TVC in coated fillets on day 21 compared to control treatment. However, the TVC level in all treatments at the end of the storage period was higher than the allowable range for human consumption (P<0.05).  The number of LAB also increased during the storage period and there was a significant difference in coated treatments compared to control (P<0.05).  The highest changes were observed in control treatment and the lowest changes were related the coated treatments. Overall, using higher percentages of sodium alginate containing probiotic bacteria can be recommended for better preservation of the fillet during the refrigerated storage. 

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Aims: The aim of this study was to investigate the effect of cooking (frying and microwave), chitosan additive and freezer storage on the fish fillet in terms of sensory and color evaluation and weight changes.
Methodes: Cultivated fish fillets, frozen at -18 ° C for 4 months. They were then transferred to the Fisheries Processing Laboratory of the Faculty of Fisheries, Gorgan University of Agricultural Sciences and Natural Resources, in the shortest possible time (day 0, day 2 and month 4). The fillets were frozen and cooked in a pan and microwave. The experiment was designed in 4 treatments: T₁ (fried sample without chitosan), T₂ (fried sample containing 1% acid-soluble chitosan), T₃ (microwave cooked sample without chitosan), T₄ (Microwave cooked sample containing 1% acid-soluble chitosan). Fillet weights were measured before and after cooking. Sensory evaluation and colorimetric evaluation of fillets were also performed after cooking.
 
Findings: The use of 1% acid soluble chitosan had no significant effect on sensory parameters and colorimetric factors (p> 0.05). Weight changes in fried fillets increased over time but decreased in microwave-cooked fillets over time.
Conclusion: The use of natural additives such as acid soluble chitosan 1% had no significant effect on the sensory indeces compared to the control group. In terms of colorimetric factors, chitosan had a positive effect on yellowness index. In terms of cooking and having a safe product, it is very important that the weight factor of the microwave cooked fillets is more favorable than the fried fillets.

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The aim of this study was to investigate the effect of chitosan as a natural preservative. Farmed fish were washed and filleted. In this study, 3 types of chitosan were investigated: acid-soluble chitosan, water-soluble chitosan and oligosaccharide chitosan. The fillets were immersed in the above solutions for 30 seconds, and then removed, and after 2 minutes, the immersion was repeated. Control samples were uncovered. The fillets were then placed at room temperature (20 °C) for 2 hours to form a coating on the fillets. 192 pieces of 100 g fish fillets were divided into 4 treatments and each treatment was divided into 4 times: treatment one as a control (without preservative), the second treatment containing 1% acid-soluble chitosan, the third treatment containing 1% water-soluble chitosan and the fourth treatment containing 1% Chitosan oligosaccharides. All samples were stored in refrigerator at 4±1 °C and their chemical parameters (Peroxide, pH, Thiobarbituric acid, Total Volatile Nitrogen) were measured on (0, 4, 8 and 12) days. All the indices of treatments had increasing trend over time. Only in the pH index of 1% acid-soluble chitosan had an irregular trend. 1% acid-soluble chitosan had the most positive effect in all treatments. Due to increase in chemical indices in all treatments, the addition different of chitosans to fish fillets could prevent or reduce them.

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The main focus for this study was to compare and evaluate the quality changes and to determine the shelf life of frozen Scomberomorus commerson fillet using quick and slow freezing methods. Scomberomorus commerson fillets were frozen by slow and quick freezing methods and kept in the freezer at -18°C for 180 days. Then proximate analysis, chemical test (Total volatile base nitrogen; TVN, Thiobarbituric acid; TBA), drip loss, fatty acids profile and sensory analysis were assessed. Generally, Ash content, TBA, and TVN, drip loss, SFA values were significantly increased during storage time where as the moisture, protein, fat, PUFA and MUFA were significantly decreased (P<0.05). The ratio of TVN, TBA and drip loss was found to be higher in slowly as against quickly frozen fish. The PUFA (19.71), MUFA (23.40) and ω3 (14.69) of the quick samples was higher than that of the slow samples (16.99, 22.64, 12.34%, respectively). Regarding sensory analysis, both samples were in acceptable condition but the quality of quick samples was better than slow frozen samples. The quick freezing method was generally much more influent on quality parameters than slow freezing method.

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Citrus peel is a natural source of antioxidants and the use of its natural extracts to improve the quality of fish is increasing. The effect of orange peel extract on the chemical and sensory properties of Huso huso fillet when refrigerated (4±1 °C) was investigated. In this study, fish fillets with aqueous solutions of ethanolic extract of orange peel (w / w 5%) or (5 ml of extract in 100 ml of solvent), orange peel extract (w / w 6%) and orange peel extract (w / w 7%) were tested as natural preservatives for 30 minutes. Control samples were immersed in distilled water for 30 minutes. Control and treated samples were packed with ethanolic extract of orange peel and stored for 15 days. Samples are then taken at regular intervals for chemical properties of pH, free fatty acid (FFA), peroxide (PV), thiobarbituric acid (TBA), total volatile nitrogen bases (TVB-N) and sensory evaluation (texture, color, odor and acceptance) were studied. Analysis of the results of chemical tests and sensory evaluation showed that orange peel extract maintains good quality characteristics and increases the shelf life of fish samples during storage at refrigerator temperature. 7% orange peel extract and then 6% and 5% orange peel extract significantly (P <0.01) delayed the oxidation and hydrolysis of fat in the samples that treated with the Orange peel extract.

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This study was designed and performed to evaluate the effect of using the active edible coating of sodium alginate containing different levels of rosemary extract on physicochemical and microbial properties of silver carp-chicken fillet mixed burger during storage. 5 treatments including uncoated burgers (control) with sodium alginate coating enriched with levels of 0, 0.5, 1 and 1.5% of rosemary extract were considered. Burgers were stored at -18 ° C for 3 months. Results showed that the use of sodium alginate coating significantly decreased the percentage of burger cooking drop. Enrichment of sodium alginate coating with different levels of rosemary extract improved its performance (P<0.05). The lowest total microbial count, psychrophilic bacteria count, TVN, PV and TBA were observed in coated burgers containing 1.5% of rosemary extract (P<0.05). There was no statistically significant difference in the performance of coatings containing levels of 1 and 1.5% of rosemary extract in decreasing TBA. Thus it is possible to use the active edible coating of sodium alginate containing 1.5% of rosemary extract to delay bacterial and oxidative spoilage of silver carp-chicken fillet burgers during a 3-month storage period at -18 ° C used.

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Supplying fresh fish and sea products is accompanied with the problem of their rapid spoilage and short shelf life. Therefore, solutions which help increase this shelf life have always been valued. Accordingly, the aim of this study was to evaluate the effect of whey protein coatings containing four different concentrations (100,200,400 and 800 IU/gr) of nisin in perch fillet for storage in refrigerator temperature. Humidity tests, Peroxide Value, Thiobarbituric acid Index, microbial load, water activity and pH were performed over coated and uncoated samples. The results indicated that increasing the shelf life in all treatments led to an increase in peroxide value, Thiobarbituric acid Index, the load of bacteria, pH and water activity, this increase was less in coated samples than the uncoated ones. On the other hand, the findings showed that whey protein and nisin coating with the of concentration 400 IU/gr of perch fillet can add 16 days to increase the shelf life in refrigerator temperature in comparison with the uncoated samples. Based on our findings, it can be concluded that using whey protein coating containing nisin with the concentration of 400 IU/gr of perch fillet as edible coating  can increase the shelf life in the refrigerator temperature.

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The aim of this study was to investigate the antioxidant effect of cucumber hydrolyzed protein (Holothuria leucospilota) and its effect on microbial and chemical properties of silver carp (Hypophthalmichthys molitrix) at refrigerator temperature. Enzymatic digestion of cucumber muscle was performed using alkalase enzyme (1.5% of weight of raw material, 55 °C and 4hr). Surimi was prepared from silver carp fillet and added to it at two concentrations of 0.5 and 0.1 mg/ kg of hydrolyzed protein. Antioxidant activity, peroxide value (PV), total volatile nitrogen bases (TVB-N), thiobarbituric acid (TBA), pH, volatile fatty acids (FFA), aerobic mesophilic bacterial count and psychrotroph bacteria on 0, 3, 6, 9, 12 and 15 days were performed. The rate of free radical scavenging by cucumber hydrolyzed protein at 0.5 and 0.1 mg/ kg was 92.24% and 62.11%, respectively, which showed a higher value than the commercial antioxidant BHT (p< 0.05). The amount of peroxide in the treatment was 0.1 mg/ kg until the ninth day and in the treatment of 0.5 mg/ kg until the twelfth day was within the allowable range. The results of TVB-N, TBA, FFA, aerobic mesophilic bacterial and psychrophilic bacteria in both treatments and on the days of the study did not exceed the allowable limit. This study showed that cucumber hydrolyzed protein is able to control bacterial load and oxidation process in silver carp surimi. Treatments containing cucumber hydrolyzed protein could increase the shelf life of surimi for 9 days compared to the control treatment.

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The aim of this study was to investigate the antioxidant and antibacterial effect of green bell pepper essential oil for qualitative comparison of silver carp sausage with meat sausage during refrigeration and also to replace some of the nitrite sodium (NaNO2) used in meat products. The essential oil was extracted from green bell pepper by the Clevenger method and ascorbic acid, phenolic compounds, free radical scavenging (DPPH) tests were performed to determine the antioxidant and antibacterial power. The essential oil extracted in three concentrations of 0, 2, and 4% was added to sausage samples prepared from silver carp and meat. Samples were stored at 4 ° C for 30 days. Chemical tests (pH, TBA, and TVN) and microbial evaluation (TMC, PTC, coliform, and mold and yeast) were performed at intervals of 5 days for 30 days in 3 replications. Results of pH, TBA (mg MDA / Kg fat), TVN (mg N / 100g Flesh), TMC, Pseudomonas, coliform and mold and yeast (CFU/g) on ​​day 30 for control treatment of fish sausage (minimum shelf-life) were 7.63, 3.4, 45.3, 11.6, 11, 2.5, and 1.5, respectively, and meat sausage treatment containing 4% of green bell pepper essential oil (maximum shelf -life) were 7.35, 1.86, 34.5, 5.3, 4.9, 0.62, 0, respectively. The results showed that 4% green bell pepper essential oil can be used as a suitable natural preservative in meat and fish sausages.

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In addition to health effects, plant extracts can be used as natural preservatives with antioxidant and antimicrobial properties in the food industry. In this study, effect of antioxidant and antimicrobial properties of ethanolic extracts of watercress on the chemical and microbial quality of rainbow trout fillet at refrigerator temperature for 12 days was investigated. After drying the leaves at darkness and room temperature extract was extracted with 45, 65, 75 and 96% ethanol solvents for 24 hours at 65 °C. The results showed a significant difference (P≤0.05) in yields and phenolic content, 0.1 mg /ml of extract 65% with an extraction efficiency of 20% the highest amount of total phenol (88.60 ± 2.46%), DPPH (84.73 ± 0%); and ABTS (83.83 ± 0.06%) were. Also, the growth inhibition of the pathogenic bacteria Listeria monocytogenes, Escherichia coli, Staphylococcus aureus and Salmonella enteritidis in sample extracted with 65% ethanol had a significant difference with other extracts (P≤0.05). Rainbow trout fillet samples in 65% ethanol extract showed lower levels of TVB-N, PV and TBA to the control treatment during storage (P≤0.05). Rainbow trout fillet samples in 65% ethanol extract showed lower levels of TVB-N, PV and TBA indices of fillets compared to control treatment during storage (P≤0.05). Talking about bacterial index, the amount of total and pseudomonas bacteria in the treatment containing the extract did not reach the maximum allowable limit (10⁶ cfu /g^-1) by the twelfth day, Indicates the effectiveness of the extract on increasing the shelf-life of fillets compared to the control.
 

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Aims: The aim of present study was production of Fatir bread fortified with rainbow trout and silver carp meats and evaluation of its quality attributes during room temperature storage.
Materials & Methods: Different concentrations of cooked rainbow trout and silver carp meat (5, 10, 15, 20 and 25%) were added to the Fatir bread and sensory properties of prepared bread were measured. Then, selected treatments were stored for 9 days at room temperature and during this time the quality attributes were evaluated. 
Findings: Results of initial sensory evaluations were showed that the Fatir bread containing 5% of rainbow trout and 10% of silver carp were accepted. Results also demonstrated that the protein, lipid and moisture content of the bread were increased with addition of the fish meat. Fatir bread fortified with fish meat had higher TVB-N, peroxide and total viable bacteria during room storage period. In terms of flavor index, the control Fatir bread was acceptable until the end of the storage period, however, the breads fortified with fish meat were within the acceptable range until day 5.
Conclusion: Can be concluded that although fortified breads showed higher nutritional value, they had lower shelf life than control bread. Between fortified breads, the quality changes were lower in the bread containing rainbow trout meat.