Effect of different cooking methods on the oxidation,proximate and fatty acid composition of silver catfish (Rhamdia quelen) fillets

The influence of seven cooking methods (boiling, conventional baking, microwave baking, grilling, deep-frying in soybean oil, canola oil, or partially hydrogenated vegetable oil) on the oxidation, proximate and fatty acid composition of silver catfish (Rhamdia quelen) fillets was evaluated. All the treatments reduced moisture and increased the protein content. The free fatty acid content of the fillets was significantly reduced by the different cooking methods, while conjugated diene levels and peroxide values decreased for all fried samples, but remained constant in the samples subjected to the other cooking methods. Boiling and baking increased thiobarbituric acid reactive substances (TBARS), while grilling and frying did not change TBARS. Boiling, baking, and grilling did not affect the silver catfish fillets fatty acid composition. Frying in canola oil increased n−3/n−6 ratio, while frying in soybean oil increased the general polyunsaturated fatty acid content, and frying in hydrogenated vegetable oil incorporated trans fatty acids in the fillets.     

Effects of Four Cooking Methods on the Proximate, Mineral and Fatty Acid Composition of Fish Fillets

The effects of baking, broiling, deep frying and cooking in a microwave oven on the proximate, mineral and fatty acid composition of grouper (Epinephelus morio), red snapper (Lutjanus campechanus), Florida pompano (Trachinotus carolinus) and Spanish mackerel (Scomberomorus maculatus) were determined. The lipid content of low fat species was not significantly changed by cooking, but lipid was lost from fatty fillets during cooking. The fatty acid composition of all fillets was not significantly changed by baking, broiling or microwave cooking. Deep fried fillets absorbed the major fatty acids in the cooking medium, and as the fillet lipid content increased the extent of absorption of fatty acids from the cooking medium decreased. Sodium, potassium and magnesium levels were decreased when low fat species were cooked, but these minerals were not lost when raw fillets containing higher lipid levels were cooked. Cooking did not significantly affect the concentration of the microelements, zinc, copper, iron and manganese.     

Sodium Lactate Affects Shelf Life And Consumer Acceptance Of Fresh Catfish (Icfalurus nebulosus, marmoratus) Fillets Under Simulated Retail Conditions

Fresh Ictulurus nebulosus, marmoratus (Speckled Bullhead catfish) fillets were tumbled under vacuum (172.32 kPa for 15 min) with either 0.1, or 2% sodium lactate solutions %(w/w) adjusted to pH 5.50, and stored at 1.11 1°C for 8 days. Shelf life of fillets treated with 2% sodium lactate was extended from 4 to 7 days. Aerobic plate counts and TBA values were lower (P < 0.05) for fillets treated with 2% sodium lactate, compared to controls. Total and fecal coliforms, psychrotrophs, pH, water activity, proximate composition and fatty acid profiles were not affected by sodium lactate. Cooking yields and sodium content were higher for fillets treated with sodium lactate compared to controls.     

Change in proximate, amino acid and fatty acid contents in muscle tissue of rainbow trout (Oncorhynchus mykiss) after cooking

Changes in proximate, amino acid and fatty acid composition of farmed, commercially important rainbow trout (Oncorhynchus mykiss) after conventional and microwave cooking were analysed. Rainbow trouts cooked in microwave ovens had statistically significant higher total protein, total fat, and ash than electrical oven‐cooked samples. The amounts of essential and nonessential amino acids were not different between cooking methods, but the difference between raw and cooked samples was significant. Lysine, leusine, methionine, threonine, valine, arginine and histidine were found most in microwave‐cooked rainbow trouts whereas isoleucine, tyrosine and phenylalanine were found most in electrical oven‐cooked samples. As total saturated fatty acid and total monounsaturated fatty acids amount were not statistically different between the cooking methods, the difference between raw and cooked fillets was found statistically significant (P < 0.05). There was no statistically significant difference between raw and cooked fillets in total n‐3 and n‐6 contents.     

CHOLESTEROL AND PROXIMATE COMPOSITION OF CHANNEL CATFISH (ICTALURUS PUNCTATUS) FILLETS – CHANGES FOLLOWING COOKING BY MICROWAVE HEATING, DEEP-FAT FRYING, AND OVEN BAKING

Effects of microwave heating, deep-fat frying, and conventional oven baking on proximate composition and concentration of cholesterol in channel catfish fillets were examined. The paired fillet technique was employed to control the variability among fish. A total of fifteen catfish were randomly assigned to the three cooking methods. All cooking procedures resulted in moisture loss. Fillets that were deep-fat fried showed the lowest moisture content but the highest fat content, respectively, among three cooking methods. The three cooking methods, on a dry weight basis, all significantly affected cholesterol concentration of cooked catfish compared with raw fillets. Deep-fat frying resulted in a significant decrease of cholesterol and showed the lowest concentration of cholesterol among three cooking methods probably due to leaching of cholesterol into frying oil.     

Comparison of the effects of four cooking methods on fatty acid profiles and nutritional composition of red mullet (Mullus barbatus) muscle

This study was performed to examine the effects of different cooking methods (frying, steaming, oven cooking, and microwave cooking) on proximate chemical composition, mineral contents, and fatty acids profiles of red mullet (Mullus barbatus) fillets. The frying process caused a significant increase in fat content (from 13.37±0.04 to 34.44±0.20 g/100 g d.w.) and reduced the proportion of the palmitic acid of 50.73% and saturated fatty acids of 56.9%. While, the proportion of polyunsaturated fatty acids (PUFA) increased from 4.04% of total fatty acids for raw fillet to 49.17% of total fatty acids for fried fillets. The steamed, oven-cooked, and microwave-cooked fillets showed the best proportion of fat content, PUFA, and ω-6/ω-3 ratio as compared with fried red mullet fillets. Na, Mg, and Zn contents of cooked fish fillets significantly decreased.     

Carcass Characteristics of Channel and Hybrid Catfish, and Quality Changes during Refrigerated Storage

Channel (Ictalurus punctatus) and hybrid (channel, I. punctutus, female × blue, I. fircatus, male) catfish were harvested from the same pond. Fillets were overwrapped or vacuum-skin packaged and stored 13 days at 4°C. Carcass characteristics, chemical, microbiological and sensory qualities were compared. No significant differences in body weight and proximate composition between the two genotypes were found. However, the visceral fat of the hybrids was significantly higher than that of channel catfish. Vacuum-skin packaged fillets had significantly lower free fatty acid levels and psychrotrophic populations than did overwrapped fillets on the 13th day of refrigerated storage.     

Effect of different precooking methods on chemical composition and lipid damage of silver carp (Hypophthalmichthys molitrix) muscle

The influence of three precooking methods (steaming, oven‐baking and microwave‐cooking) on the chemical composition and lipid quality of silver carp fillets was evaluated. The changes in protein, fat and moisture were found to be significant for all the treatments (P ≤ 0.05). The iron content in the samples subjected to steam‐cooking increased; however, the other precooking methods did not change the mineral contents (P ≥ 0.05). The free fatty acid content of the fillets did not change by the different precooking methods, while thiobarbituric acid (TBA) values increased for oven‐ and microwave‐cooked fillets and remained constant in the steam‐cooked samples. Conjugated diene and browning colour formation levels significantly increased in the oven‐baked fillets. Oven‐baking and microwave‐cooking marginally affected the fatty acid composition of the silver carp. On comparing the raw and precooked fillets, steam‐cooking was found to be the best precooking method on retaining nutritional constituents.     

Potassium acetate and potassium lactate enhance the microbiological and physical properties of marinated catfish fillets

Sodium or potassium salts such as lactate and acetate can be used to inhibit the growth of spoilage bacteria and food-borne pathogens, and thereby prolong the shelf-life of refrigerated seafood. However, minimal information is available regarding the combined effects of potassium salts (acetate and lactate) with an agglomerated phosphate blend on the quality and safety of refrigerated catfish fillets. The objective of this study was to determine the microbiological and quality characteristics of marinated catfish fillets treated with organic acid salts. Catfish fillets were vacuum-tumbled with a brine solution with and without the added organic acid salts, at 10% over initial, raw weight prior to tray-packing and storage at 4 °C for 14 d. Fillets were evaluated for yields, color, pH, tenderness, consumer acceptability, and shelf-life. No differences (P > 0.05) existed among the treated and untreated fillets with regards to solution pick-up and pH, but all treated fillets increased (P < 0.05) cooking yields and Intl. Commission on Illumination (CIE) a* values, and decreased (P < 0.05) CIE L* and b* values in the catfish fillets when compared to the untreated fillets. The fillets treated with a combination of potassium acetate and potassium lactate had lower (P < 0.05) psychrotrophic plate counts and lower spoilage scores than the control treatments on days 7, 10, and 14. In addition, consumers preferred (P < 0.05) treated catfish fillets (fried) with respect to appearance, flavor, and overall acceptability over the negative control. In conclusion, the combination of potassium acetate and potassium lactate enhanced sensory quality and extended the shelf-life of refrigerated catfish fillets.     

Influence of Commercial Diets on Quality Aspects of Cultured Gulf of Mexico Surgeon (Ancipenser oxyrinchus desotoi)

ABSTRACT: Cultured sturgeons were fed commercially available diets formulated for hybrid bass, catfish, and trout. The impact of these diets in the quality of the edible muscle was investigated through determination of processing yields, proximate compositions, fatty acid profiles, muscle color, and sensory characteristics. Sturgeon fed the catfish diet were significantly smaller but dressed fillets (percent live weight) were similar for all feeds. Consumer visual acceptability scores were highest for fillets from fish fed the catfish diet, and color differences were determined. Sturgeon fillets from fish fed the trout diet presented a yellowish orange coloration instead of a pale pink coloration. Results show that the diets tested had no detrimental impact in the composition of sturgeon fillets.     

Nutrients and Chemical Residues in One- to Two-Pound Mississippi Farm-raised Channel Catfish (Ictalurus punctatus)

Composite samples of Mississippi farm-raised channel catfish (FRCC) fillets were analyzed at four different seasons for the following: proximate composition, cholesterol, fatty acids, eight vitamins, eleven minerals, four heavy metals and eight chemical residues. Nutrients and other compounds did not vary appreciably with season. Mississippi FRCC were higher in fat, calories and thiamin compared with USDA and wild catfish data and had much less cholesterol than previously reported. Monounsaturates comprised over half the fatty acids in FRCC and omega-3 fatty acid content was low. Chemical residues were not detectable or present in extremely small amounts.     

Comparison of proximate composition,amino acid and fatty acid profiles in wild,pond‐ and cage‐cultured longsnout catfish (Leiocassis longirostris)

The proximate composition, amino acid and fatty acid profiles in the fillets of wild, pond‐ and cage‐cultured longsnout catfish (Leiocassis longirostris) were determined to identify nutritional differences. Wild fish showed higher (P < 0.05) moisture and viscerosomatic index (VSI), but lower (P < 0.05) protein, ash and gross energy than cage‐cultured fish. Pond‐cultured fish contained lower (P < 0.05) protein and ash contents, but higher VSI compared to cage‐cultured fish. The amino acid of glycine content was higher (P < 0.05) in wild fish than in pond‐ and cage‐cultured fish. Most of the fatty acids had a significant difference among all fish groups. The percentages of total polyunsaturated fatty acids (∑ PUFAs) were higher (P < 0.05) in wild and pond‐cultured fish than in cage‐cultured fish. Pond‐cultured fish had higher (P < 0.05) ∑ n‐3 PUFAs, eicosapentaenoic acid (EPA), docosahxaenoic acid (DHA) and ∑ n‐3/∑ n‐6 PUFAs ratio than wild and cage‐cultured fish. The differences among the wild, pond‐ and cage‐cultured fish may be attributed to dietary components and environmental conditions of the fish.     

Compositional and chill storage characteristics of microwave‐blanched sutchi catfish (Pangasianodon hypophthalmus) fillets

The effect of microwave blanching on quality characteristics of vacuum and conventional polyethylene‐packed sutchi catfish fillets was evaluated under chilled condition. Emphasis has been given to retain the sensory characteristics such as colour and textural properties, which is a major problem in sutchi catfish fillets during extended chill storage. In general, microwave blanching imposed minimum changes on fatty acid and mineral composition of fish meat. A marginal increase in fat content was recorded after microwave heating of fish fillets. The microwave‐blanched fillets showed minimum cooking loss of 3.2 mL per 100 g meat. A slower increase in spoilage parameters was obtained with microwave‐blanched samples compared with unblanched samples, demonstrating the higher storage stability of the sample under chilled conditions. Microwave heating of fish fillets coupled with quick‐chilling and packing under vacuum improved the colour and texture stability of sutchi catfish fillets to a considerable extent. Microwave blanching increased the hardness and chewiness values and decreased the stiffness values of fish fillets. The biochemical and sensory evaluation of microwave‐blanched and vacuum‐packed sutchi catfish fillets showed extended storage life of 21 days, compared with 12 days for unblanched vacuum‐packed samples.     

Composition and quality attributes of conventionally and organically farmed Pangasius fillets (Pangasius hypophthalmus) on the German market

A range of conventionally and organically farmed Pangasius or sutchi catfish fillets available on the German market were analysed to compare both composition and quality. Differentiation of Pangasius hypophthalmus from Pangasius bocourti was achieved by RFLP-SSCP analysis. The protein content of conventionally farmed fillets ranged between 13.3 and 15.7%, whereas organically produced fillets had significantly higher protein contents of between 17.0 and 17.4%. No difference in the fat content between farming methods was observed, which varied between 1.4 and 3.2%. Polyunsaturated fatty acids represented about 24% of the total fatty acids with a high level of linoleic acid. The comparison of the proximate composition indicated that water was added to most of the conventionally farmed products, in different amounts, as well as water-binding capacity enhancing additives. Differential scanning calorimetry was used to demonstrate the presence of polyphosphate on muscle proteins. Differences in texture, water-binding capacity and colour are discussed.     

Effect of different cooking methods on vitamins,minerals and nutritional quality indices of orange-spotted grouper (<Emphasis Type="Italic">Epinephelus coioides</Emphasis>)

This study aimed to evaluate the nutritional value [proximate, fatty acid profiles, vitamins and minerals and also nutritional quality indices (NQI)] of orange-spotted grouper (Epinephelus coioides) prepared according to common consumer techniques: raw, poached, steamed, microwaved, pan-fried and deep-fried (in olive oil). There was an increase in protein, lipid and ash contents in cooked fish as compared to raw fish fillets. Cooking treatment had no significant effect on total n-3 fatty acids except for deep-fried fillets. Cooking methods had no significant effect on total n-6 fatty acids. In all the cooking methods, n-6 fatty acids were well preserved. There was no significant difference in the Mn, Zn, Ca and Fe contents of fillet between raw and cooked samples. Vitamin D content in all cooking methods did not differ significantly. None of cooking methods had a significant effect on vitamin A except for deep-frying fillets. However, vitamin B1 and B3 contents of cooked fish significantly decreased. Considering the overall nutritional quality indices, vitamin and mineral contents, steaming is the best cooking method.     

Authentication of raw and cooked freeze-dried rainbow trout (Oncorhynchus mykiss) by means of near infrared spectroscopy and data fusion

This study investigated the possibility of using near infrared spectroscopy (NIRS) for the authentication of raw and cooked freeze-dried rainbow trout (Oncorhynchus mykiss) fillets. Latent variable models applied on the spectral data were developed and used to estimate proximate composition, fatty acid profile, fillet yield and cooking loss, and to classify the available dataset by the rearing farm and genetic strain of each sample.Results showed that NIR spectra can be used both to accurately estimate several chemical properties and to classify samples by rearing farm. In order to classify samples by genetic strain instead, a data fusion approach in which color and mechanical information were combined with spectral data was used. No major differences were observed between the results obtained from raw freeze-dried fillets and those obtained from cooked freeze-dried fillets, except for the estimation of certain chemical constituents of interest such as C22:6 n − 3 and polyunsaturated fatty acid content, both of which were better estimated from cooked freeze-dried fillets.     

Proximate and fatty acids composition of the muscles and viscera of Asian catfish (Pangasius bocourti)

The objective of this research was to analyse the distribution pattern of proximate composition and fatty acid profiles in different portions of Asian catfish (Pangasius bocourti). The lipid content was found amongst different portions, ranging from 2.95% to 93.32%, being lowest in the caudal–dorsal portion and highest in the viscera. Protein, moisture and ash contents were inversely proportional to the lipid content amongst the body portion. There was no specific tendency for the changes of each fatty acid composition from the different portions. Monounsaturated fatty acid (MUFA) was the most predominant fatty acid found in all tissues, ranging from 32.7% to 39.9%, followed by saturated fatty acids (SFA) ranged from 30.2% to 36.5% of total fatty acid, whereas the total polyunsaturated fatty acids (PUFA) content was the lowest, ranging from 14.8% to 24.0%. This study revealed that the proximate compositions and fatty acids deposition in Asian catfish varied markedly throughout the body portion.     

Proximate and fatty acid composition and cholesterol content of different cuts of guinea fowl meat as affected by cooking method

BACKGROUND: Poultry is one of the leading meat products in South Africa, and its nutritional composition can be affected by the cut and cooking method. Limited food composition data are available for typical South African poultry products. This study investigated the effect of different cuts and cooking methods on the proximate and fatty acid composition as well as the cholesterol content of guinea fowl (Numida meleagris) meat. RESULTS: The open‐roasting method produced the highest moisture content for all cuts, and the baking bag method the lowest. The baking bag method resulted in the highest protein content. Cooking method had no effect on fat content, although breast had the lowest and thigh the highest fat content. Ash content was highest in the open‐roasted drumstick. All cuts, regardless of cooking method, had a favourable polyunsaturated/saturated fatty acid (P/S) ratio (>0.4). Their n‐6/n‐3 ratio was also within the recommended beneficial range (<4:1). Both cooking method and cut affected cholesterol content. CONCLUSION: Different cuts of guinea fowl vary in proximate and fatty acid composition as well as in cholesterol content, which in turn is affected to varying degrees by cooking method. Copyright © 2012 Society of Chemical Industry     

Fish Oil Dietary Effects on Fatty Acid Composition and Flavor of Channel Catfish

A typical channel catfish diet was supplemented with 0, 1.5, and 3% menhaden oil. Fillets were subjected to lipid, fatty acid, and TBA analyses. After 6 mo storage at ?18°C, fillets were again analyzed for TBA value and flavor panel profile. Fillets from catfish fed diets with 1.5 and 3% supplemental fish oil had elevated levels of n-3 fatty acids (P<0.05). TBA number and off-flavor attributes were not affected by treatments. Menhaden oil supplementation up to 3% enhanced the content of n-3 fatty acids in channel catfish fillets without adversely affecting flavor attributes or storage quality.     

Phosphate Type Affects the Quality of Injected Catfish Fillets

ABSTRACT:  Catfish fillets were injected to 115% over green weight prior to tray-packing and storage at 4 °C for 1, 4, 8, and 11 d. Fillets were evaluated for yields, surface color, pH, cooking loss, tenderness, purge loss, and shelf-life. All phosphate treatments increased ( P  < 0.05) fillet tenderness, but the agglomerated blend of sodium phosphates (AGSP) increased ( P  < 0.05) pH and yields, and decreased ( P  < 0.05) CIE  L * and CIE  b * values. Psychrotrophic plate counts (PPC) of fillets treated with the agglomerated blend of polyphosphates (AGPP) were lower ( P  < 0.05) than the control at each storage time, but PPC of all samples reached 7 log CFU/g by day 8 of storage. All agglomerated phosphates and STP (sodium tripolyphosphate) improved yields and quality when compared to the nonmarinated control. However, AGSP was the most effective phosphate at increasing pick-up and yields and decreasing cooking loss due to the pH effect that causes more water to be trapped within the food system. Major quality differences may not have occurred between STP and agglomerated phosphates (other than AGSP) since injection relies solely on pH and ionic strength for marinade pickup, whereas tumbling also relies on mechanical action, which relies more on the presence of various phosphate chain lengths and solubility to impact yields. All phosphate treatments improved the quality of tray-packed, refrigerated catfish fillets that were enhanced through multineedle injection. However, AGSP also increased fillet pH, optimized yields, and improved color.
Practical Application: Use of an agglomerated phosphate blend with a high pH (AGSP) maximized the yield of catfish fillets that were marinated through multineedle injection. In addition, STP and agglomerated phosphate blends increased the yield and tenderness of catfish fillets when compared to the nonmarinated control.