الفهرس 
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Abstract
Carp fish species are the most widely cultured species in Egypt, due to its fast growth rate, easy cultivation and high feed efficiency ratio however,they have low consumer preference and hence limited market, this is due to the presence of intramuscular bones. Grass carp fish (Ctenopharyngodon idella) samples were obtained from local market (El-Obour, Fish Market, Egypt) during May 2021. They were transported using ice box to Fish Technology and Processing Lab., Elkanater Elkhairia Station for Fish Research, National Institute of Oceanography and Fisheries. Samples were carefully washed using tap water, beheaded, eviscerated, skin removed, manually filleted, washed again, drained (yield of edible part was 42.85 %), cooked in autoclave and then dried in the oven at 50⁰ until completely dry for 48h. It was grinded with excluding some impurities (the small and dark parts were removed) for preparing fish powder.
Recipe ingredients:-
The following treatments were made.
1) Control Sample
It composed of 1 kg flour (½ kg wheat flour + ½ kg Corn flour). 2% Sodium chloride and 1 gm Zaater (dried thyme) were blended with 550 ml water, then mixed with 110 ml sunflower oil. All ingredient used in this study were purchased from local market. After that it cut into equal parts with a very thin high in a circular shapes then put it in a pan (a minute for every side) then divided every interaction into two parts the first part was for frying and the second was for baking.
(2) 5% sample : 50 grams of fish flour (½ kg wheat flour + ½ kg Corn flour) was replaced with 50 grams of fish powder (950 Flour mixture + 50 gm fish Powder).
(3) 10% sample :100 g of mixed flour (½ kg wheat flour + ½ kg Corn flour) was replaced with 100 g of fish Powder (900 flour mixture + 100 g fish Powder).
(4) 15% sample : 150 gm of mixed flour (½ kg wheat flour + ½ kg Corn flour) were replaced with 150 g of fish powder (850 flour mixture + 150 g fish powder).
(5) 20% sample : 200 gm of mixed flour (½ kg wheat flour + ½ kg Corn flour) were replaced with 200 gm fish Powder (800 flour mixture + 200 gm Fish Powder).
Fish snacks will be cooked by two methods (baked in oven and fried in deep oil).
Two cooking methods; deep frying in corn oil using electrical fryer at 220oC for 3-5 min and cooking for 10 min (baked) using SAMSUNG oven (Model no. M1932, 28 L., Korea) were applied.After cooking processes the products were flavored with cheese flavor, packed and stored under ambient temperature for three months.
The results obtained showed the following orders:
- Raw grass carp fish
•The yield of grass carp flesh achieved by hand-filleting was 42.85%. The remaining part represents 57.15%. This is due to the high containing of gastro-intestinal and to the digestive tract length.
•Proximate analysis of grass fish flesh: The moisture, crude protein, lipid and ash content of raw fish flesh were 73%, 17%, 7% and 2%, respectively on wet weight basis.
•physico-chemical quality criteria of grass carp flesh recorded TVB-N, TMA-N, and TBA were 22.4 mg/100g, 0.85 mg/100g and 0.90 mg MAD/kg sample, respectively, while the pH value was 5.46.
•TVB, 0.89 - 5.62 mg/100g TMA, 0.19 - 5.29 mg MA/kg sample, and the pH values were 6.11- 6.73.
•Some Major elements concentrations (Ca, Mg, Na and k mg/100g ww) of raw grass carp flesh are demonstrated.
•Ca and Mg are the most dominant and the highest concentration in fish flesh. Raw fish flesh contained 450 mg/100g Ca, 180 mg/100g Mg, 350 mg/100g Na and 260 mg/100g K.
• Raw grass carp flesh as compared with the previous studies. It was expressed with Total bacterial count (TPC) which recorded 1.0×103 cfu/g.
-Fish powder
•The proximate analysis of fish powder: the moisture, crude protein, lipid and ash content were 9.66%, 77%, 18% and 4.3% respectively on dry weight basis.
•Major elements concentrations of fish flour grass carp were demonstrated. K was the most dominant element and the highest concentration in fish powder and other treatments being 1040 mg/100g (dw).The microbial quality criteria of carp fish flour was expressed with total plate count (TPC). The present count of TPC (1.0× 102 cfu/g) was considered under the maximum permissible limits and lower than reported by Egyptian Standard Specifications.
•Ten essential amino acids were recorded in both fish flour and raw fish. Total essential amino acids recorded its lowest value in raw fish (29.81 gm/100g) while the highest one was recorded at fish powder (40.61 gm/100g). Lysine, Leucine and Valine were the most dominant Essential amino acids; being 6.50, 4.96 and 3.39g /100g in raw and 10.31, 6.07 and 5.12 g /100g in fish powder, respectively.
•Seven non-essential amino acids were recorded in both fish powder and raw fish.
•Total non-essential amino acids recorded its highest value in raw fish (32.45 g /100g) while the lowest one was recorded at fish powder (30.4 g /100g). Glutamine and Asparagine were the most dominant non-essential amino acids; being 9.72 and 6.64 g /100g in raw and 10.55 and 6.59 g /100g in fish powder, respectively. The ascending orders of non-essential amino acids were Glutamine Asparagine, Arginine, Glycine Alanine, Serine and Proline.
•The effect of different cooking methods on the processed snacks with storage at ambient temperature (28°C) for three months on moisture content of baked and fried (grass carp fish) products. Initial moisture content of fried and baked snacks products of grass carp fish showed a relatively increase with increasing fish powder concentration.It recorded 2.78±0.45%, 3.21±0.14, 2.68±0.00, 2.77±0.50 and 3.47±0.10 %, fried snacks at zero time respectively in after processing directly, but in baked snacks at zero time products. Initial moisture was increased being, 4.60±0.13, 5.21±0.15, 3.33±2.98, 2.65±3.13 and 4.94±0.01%, respectively.
•from these results could be noticed the general trend of moisture contents of fish fried snacks in present study were lower than which of fish baked snacks. During storage period, Moisture contents of fried and baked snacks did not recorded a remarkable effect in the study due to well packing of the products. This situation could be discussed according to the difference in the type and amount of ingredients percent that were used in snacks products.
•Effect of different cooking methods on crude protein of fish snacks at ambient temperature showed a slightly increase in baked than fried for three months. The levels of protein content (Dw) at zero time were 4.89±1.79, 11.42±0.70, 18.23±1.66, 21.94±1.74 and 35.15±3.90% for control, 5%, 10%, 15% and 20% in fried snacks, respectively. Baked snacks showed a remarkable decrease in protein at all products during the storage period. It recorded 13.58±5.55, 24.37±1.14, 30.23±3.08, 32.19±2.90 and 37.78±15.80 % for control, 5%, 10%, 15% and 20% in baked snacks at zero time, respectively.
•The Increases in chemical composition of fishery products especially protein content are due to the increase in fish powder percent.
•The levels of lipid content (dw) at zero time were 2.1±0.09, 1.9±0.47, 2.74±0.25, 3.00±0.08 and 3.98±0.42 % for control, 5%, 10%, 15% and 20% in fried snacks, respectively.Baked snacks showed a remarkable decrease at all products during the storage period. It recorded 0.56±0.43, 0.75±0.18, 1.34±0.15, 1.93±0.33 and 4.60±0.03 % for control, 5%, 10%, 15% and 20% in baked snacks, respectively.
•This variation in lipid content of cooked carp products is due to fish powder, recipes and cooking method used. Also, it was found that, the loss in its content in case of baked snacks is due to drip of part of lipid during this process.
•The increase in lipid content of the fried fish products was related to oil absorption during the cooking process.
•The levels of ash content (D w) at zero time were 3.33±0.08, 2.24±0.26, 3.50±0.82, 2.87±0.08 and 2.44±0.14 % at Control, 5%, 10%, 15% and 20% in fried snacks, respectively. Baked snacks recorded 3.06±0.13, 2.80±0.08, 3.33±0.08, 3.04±0.16 and 3.00±0.47 % for control, 5%, 10%, 15% and 20% in baked snacks, respectively. At the end of storage period (90 days), the data not recorded trend. These slightly variation in ash content of snacks carp products due to recipes and cooking method used too.
•The levels of carbohydrates (D w) at zero time were 87.47±0.22, 81.23±0.23, 72.85±0.41, 69.42±0.46 and 54.96±0.29 % for control, 5%, 10%, 15% and 20% in fried snacks, respectively. At baked snacks, it recorded 78.20±0.55, 66.87±0.99, 62.26±1.01, 60.87±1.55 and 49.68±0.43 % for control, 5%, 10%, 15% and 20% in baked snacks, respectively.
•Quality criteria of grass carp snacks produces: The effect of different cooking methods on TVB content of the processed snacks which storage at ambient temperature (28°C) for three months. The TVB-N contents at zero time increased gradually with the increasing of fish powder concentration. The levels of TVB-N (w.w.) at zero time were 4.20±0.00, 12.30±0.99, 12.60±1.98, 15.30±2.97 and 20.60±1.98 % for control, 5%, 10%, 15% and 20% in fried snacks, respectively. At baked snacks, it recorded 9.80±0.00, 10.50±2.97, 19.40±1.98, 21.51±0.10 and 23.24±1.83 % for control, 5%, 10%, 15% and 20% in baked snacks, respectively.
•The levels of TMA-N (w w) at zero time were1.50±0.00, 2.75±0.21, 2.95±0.07, 2.75±0.35 and 2.2±0.99 for control, 5%, 10%, 15% and 20% in fried snacks, respectively. While, it recorded 3.2±1.63, 3.80±0.71, 2.65±1.63, 2.50±0.00 and 2.35±0.21 for control, 5%, 10%, 15% and 20% in baked snacks, respectively.
•The levels of TMA-N (D w) at zero time were1.50±0.00, 2.75±0.21, 2.95±0.07, 2.75±0.35 and 2.2±0.99 for control, 5%, 10%, 15% and 20% in fried snacks, respectively. While, it recorded 3.2±1.63, 3.80±0.71, 2.65±1.63, 2.50±0.00 and 2.35±0.21 for control, 5%, 10%, 15% and 20% in baked snacks, respectively.
•Results showed that the TBA values in fried and baked snacks products were1.26±0.22, 1.63±0.75, 1.64±0.34, 0.30±0.04 and 0.80±0.42 mg MDA/kg for control, 5%, 10%, 15% and 20% in fried snacks, respectively. While, it recorded 0.70±0.19, 0.31±0.00, 0.28±0.01, 0.25±0.04 and 0.35±0.01 mg MDA/kg for control, 5%, 10%, 15% and 20% in baked snacks, respectively.
•TBA values of the products in the present study were lower than such proposed limits.
•Physico-chemical and microbial quality criteria were increased with the increasing of fish powder percent after cooking and storage.
•Therefore, 10% snacks showed the best treatment and the best quality product. This product was selected for accurate major elements evaluation and amino acid analysis.
•pH values between (5.45 - 6.33) were proposed as acceptance limit of fish, and values above 7 were considered to be spoiled. pH for all the snacks products recorded in the acceptable ranges (5.45-6.33)during the study.
•The results indicated that the TPC counts were very low and fluctuated between 1×102, 8×102 and 13×102 cfu/g in fried snacks, while, in fried snacks it ranged between 1×102 and 9×102 cfu/g.
•TPC considered within the permissible limits, it showed a slightly increase in the third month which due to the ambient temperature and there is no any methods of storage.
•Effect of different cooking methods on sensory evaluation of fried and baked snacks which storage at ambient temperature (28°C) for three months. Color, texture, odor, taste and overall acceptability recorded high scores at fried snacks more baked snacks.
•Overall acceptability values for all the studied snacks products were in Table 23. All the snacks products during the study showed a good acceptability from the panelists. The highest accepted treatment (the most liked) was 10 % fish powder in each fried and baked being 9.05 and 8.85, respectively. These values are slightly decreased storage at ambient temperature (28°C) for three months in each fried and baked being 8.59 and 8.27, respectively.
•Depending on the best values observed of sensory evaluation of the studied snacks product. 10% snacks product (fried and baked snacks) showed the best treatment and the best quality product.
•Ten Essential amino acids were recorded in both fried and baked fish snacks.
•Total essential amino acids recorded its highest value in baked fish snacks 10% (4.09 g /100g) while the lowest one were recorded at fried fish snacks 10% (3.85 g /100g). This indicates that the baked fish snacks 10% is more valuable depending on essential amino acids.
•These products were selected for determination of its nutritional value by measuring major elements (Ca, Mg, Na and K) concentrations and amino acid analysis (Essential and non-essential).
•Ca and K recorded the highest values with adding 10% Fish flour, at fried snacks being 120&260 while at baked snacks Ca and K recorded also high value being 120&240, respectively.
•Lysine, leucine and valine were the most dominant essential amino acids; being 6.50, 4.96 and 3.39g /100g in raw and 7.14, 4.22 and 3.56 g /100g in fish flour, respectively. In the processed snacks, all the essential amino acids had showed a remarkable decrease.
•Seven non-essential amino acids were recorded in both fried and baked fish snacks.
•Total non-essential amino acids recorded its highest value in baked fish snacks 10% (6.08 g /100g) while the lowest one was recorded at fried fish snacks 10% (5.47 g /100g). This also indicates that the baked fish snacks 10% is more valuable depending on non-essential amino acids.
•Glutamine and Asparagine were the most dominant non-essential amino acids; being 9.72 and 6.64 g /100g in raw and 10.55 and 6.59 g /100g in fish powder, respectively. Also, Glutamine and Asparagine the most dominant non-essential amino acids ofthe processed snacks.Although, all the non-essential amino acids was showed a remarkable decrease. Glutamine recoded the highest value in fried and baked fish snacks being 2.35 and 2.68 g /100g, respectively.