الفهرس 
INTRODUCTION
Fish SaltingOnly 14 pages are availabe for public view
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Abstract
Part I: Nutritive value of commercially salted fish
The present study was performed to evaluate the nutritive value of 42 samples of commercially available Egypt salted fish products (Meloha) including 21 Hydrocynus forskalli and 21 Alestes baremose. The samples collected randomly from salted retail outlets in Assiut City.
Evaluation the nutritive value of commercially salted fish through determination the chemical composition of examined salted fish including moisture, fat, protein, Ash, carbohydrate, cholesterol and salt (Nacl) contents. In addition to determination the energy value of examined salted fish and determination the level of protein deterioration and lipid oxidation of commercially salted fish by determination of chemical indicates spoilage tests including Total Volatile Base Nitrogen (TVB-N) content and Thiobarbituric acid value.
Moisture percentage of Hydrocynus forskalli was 46.47% and 62.17% a minimum and a maximum with a mean value of 56.29 + 0.79%, and moisture percentage of Alestes baremose was 43.01 % as a minimum and 55.91 % as a maximum, with a mean value of 52.05 + 0.61%.
Fat percentage of Hydrocynus forskalli was 1.86 % as a minimum, and 8.37 % as a maximum with a mean value of 5.57 + 0.43%, and that of Alestes baremose was 3.92 % as a minimum and 15.45 % as a maximum with a mean value of 8.29 + 0.65%.
Protein percentage of Hydrocynus forskalli was 15.77% as a minimum and 28.2% as a maximum with a mean value of 22.228 ± 0.733%, and that of Alestes baremose was 18.92% as a minimum and 26.77% as a maximum with a mean value of 21.731± 0.429%.
Ash percentage of Hydrocynus forskalli was 12.8% as a minimum and 18.6% as a maximum with a mean value of 15.393 ± 0.301%, and that of Alestes baremose was 14.2% as a minimum and 19.95% as a maximum with a mean value of 17.393 ± 0.418%.
Carbohydrate percentage of Hydrocynus forskalli was 0.3% as a minimum and 0.77% as a maximum with a mean value of 0.438 ± 0.029%. In respect to Alestes baremose the carbohydrate percentage was 0.32% as a minimum and 0.63% as a maximum with a mean value of0.423 ± 0.017%.
Cholesterol content of Hydrocynus forskalli was 0.43 mg/100g as a minimum and 46.74 mg/100g as a maximum with a mean value of 14.134 ± 2.792 mg/100g and that of Alestes baremose was 1.578 mg/100g as a minimum and 70.526 mg/100g as a maximum with a mean value of 23.423 ± 5.487 mg/100g.
Sodium chloride content of the examined Hydrocynus forskalli was 12.285 % as a minimum and 18.42% as a maximum with a mean value of 14.541 ± 0.362%. In respect to Alestes baremose the Sodium chloride content was 14.04 % as a minimum and 23.11% as a maximum with a mean value of 17.564± 0.572%.
Energy value of Hydrocynus forskalli was 105.58 kcal/100g as a minimum and 184.9 kcal/100g as a maximum with a mean value of 140.71 + 4.35 kcal/100g. In respect to Alestes baremose the energy value was 124.32 kcal/100g as a minimum and 238.09 kcal/100g as a maximum with a mean value of 164.29 + 6.01 kcal/100gm.
The mean value of TVB-N content for the examined Hydrocynus forskalli was 233.8 mg/100g as a minimum and 499.8 mg/100g as a maximum with a mean value of 343.362 ± 17.874 mg/100g and that of Alestes baremose was 177.8 mg/100g as a minimum and 548.8mg/100g as a maximum with a mean value of 373 ± 15.616 mg/100g. There wasn’t significant difference between Hydrocynus forskalli and Alestes baremose in TVB-N content.
The TBA value of Hydrocynus forskalli was 0.007 mg/ MDA/Kg as a minimum and 0.228 mg/ MDA/Kg as a maximum with a mean value of 0.108 ± 0.016 mg/ MDA/Kg and that of Alestes baremose was 0.005mg MDA/Kg as a minimum and 0.432 mg/ MDA/Kg as a maximum with a mean value of 0.114 ± 0.024mg MDA/Kg. There wasn’t a significant difference between Hydrocynus forskalli and Alestes baremose in TBA value. There was a negative strong significant correlation between length and weight of Hydrocynus forskalli and TBA value.The results of TBA value within the acceptable limits.
Part II: Effect of salting process on experimental salted fish
Salted fish (Meloha) was prepared in the laboratory. The fish were salted in tin containers using a salt to fish ratio of 1.5:10(w/w) and held for ripening at room temperature (25±2 0C) .Evaluate the effect of salting process on fish along the time of salting from fresh fish till ripening at 50 day.
The effect of salting on moisture content of Hydrocynus forskalli and Alestes baremose showed that highly content of moisture of Hydrocynus forskalli and Alestes baremose registed at fresh fish was 67.3% and 64.76%, respectively. The lower value at 50th day was 51.82% and 50.6%, respectively. Moisture content decrease with the increase in time of salting storage days and in our study, the highest deficiency percent recorded at the end of experimental test (50th day). That clears; the 50th day is recommends time for consuming salted fish.
The effect of salting process on fat content of Hydrocynus forskalli and Alestes baremose showed that highly content of fat of Hydrocynus forskalli and Alestes baremose registed at fresh fish was 5.4% and 9.14%, respectively. The lower value at 20th day was 2.76% and 5%, respectively. The value at 50th day was 4.02% and 8.24%, respectively. With time aging of salted fish, the fat content decrease with time and reach a maximum deficiency percentage of fat at 20th day and a minimum deficiency percentage at 50th day and also decrease fat content with aging is limited specially when reach 50th day.
The effect of salting on protein content of Hydrocynus forskalli and Alestes baremose showed that highly content of protein of Hydrocynus forskalli and Alestes baremose registed at fresh fish was 24.97% and 24.11%, respectively. The lower contents at 20th day were 22.99% and 20.74%, respectively. The value at 50th day was 24.88% and 22.46%, respectively. With time aging of salted fish, the protein content decrease with time and reach a maximum deficiency percentage of protein at 20day in both fish species and then the deficiency percentage decline at 50day. The salting process have limited effect on protein content specially at 50th day of salting storage using a salt to fish ratio of 1.5 : 10(w/w) at room temperature.
The effect of salting on ash content of Hydrocynus forskalli and Alestes baremose showed that lowest value of ash content of Hydrocynus forskalli and Alestes baremose registed at fresh was 1.6% and 1.49%, respectively. The highest value at 20th day was 20.75% and 22.77%, respectively. The value at 50th day was 18.98% and 18.4%, respectively. With aging of salted fish, the ash content increase with time.
The effect of salting on carbohydrate content of Hydrocynus forskalli and Alestes baremose showed that highly content of carbohydrate of Hydrocynus forskalli and Alestes baremose registed at fresh fish was 0.73% and 0.5% respectively. The lower content at 50th day was 0.3% in the two fish species. With time aging of salted fish, the carbohydrate content decrease with time percentage and a maximum deficiency percentage of carbohydrate registed at 50th day in both fish species.
The effect of salting on cholesterol content of Hydrocynus forskalli and Alestes baremose showed that cholesterol content in fresh fish was 2.88 and 4.17 mg/100mg in Hydrocynus forskalli and Alestes baremose, respectively. The registed cholesterol content along time aging of salted fish at 2nd ,7th ,10th ,15th ,20th and 50th day was 2.44 , 0.96 , 3.85 , 5.8 , 5.1 and 1.2 mg/100mg, respectively in Hydrocynus forskalli and 4.49 , 0.32 , 3.2 , 3.8 , 2.5 and 4.8 mg/100mg, respectively in Alestes baremose. With time aging of salted fish, the cholesterol content not affect by time of salting storage. Mostly there was a significant difference in cholesterol content between the fish species within the time interval of salting storage process.
The effect of salting on sodium chloride content of Hydrocynus forskalli and Alestes baremose showed that the minimum content of sodium chloride of Hydrocynus forskalli and Alestes baremose registed at fresh fish was 0.585% and 0.95%, respectively. Then the sodium chloride begins to increase gradually till reach the maximum content 26.32% and 25.74%, respectively at 20th day. Then decrease to 23.4% in both fish species at 50th day. With time aging of salted fish, the sodium chloride content increase and that associated with decrease moisture percentage. Also at 50th day of salting storage the sodium chloride percentage nears the recommended percentage of Egyptian organization for standardization and quality control (2005).
The effect of salting on energy value of Hydrocynus forskalli and Alestes baremose showed that the highest content of energy value of Hydrocynus forskalli and Alestes baremose registed at fresh fish was 151.4 and 180.7 kcal/100g, respectively. The lowest value at 20th day was 118 and 131.18kcal/100g, respectively. While at 50th day reach 136.9 and 165.2 kcal/100g, respectively. With time aging of salted fish, the energy value decreased to some extend with time aging.
The effect of salting on TVB-N content of Hydrocynus forskalli and Alestes baremose showed that the TVB-N registed in fresh fish in Hydrocynus forskalli and Alestes baremose was 19.6 and 30.8 mg/100g, respectively. Then the TVB-N begins to increase gradually from zero day till reach 93.8mg/100g in both Hydrocynus forskalli and Alestes baremose at 50th day of salting process. With time aging of salted fish, the TVB-N steady increased. The result was within the acceptable limits of salted fish at 50th day of storage.
The effect of salting on lipid oxidation and thiobarituric acid value of Hydrocynus forskalli and Alestes baremose showed that the TBA increase in Hydrocynus forskalli and Alestes baremose from 0.08 and 0.15 mg malondialdehyde (MDA)/Kg, respectively in fresh fish to reach 0.2 mg MDA/Kg in Hydrocynus forskalli at 10th day and 0.26 mg MDA/Kg in Alestes baremose at 7th day, then decrease to 0.07 mg MDA/Kg in Hydrocynus forskalli at 15th day and 0.10 mg MDA/kg in Alestes baremose at 10th day after that become to increase to reach 0.31 and 0.38 mg MDA/Kg at 50th day in Hydrocynus forskalli and Alestes baremose, respectively. With time aging of salted fish, the TBA values is