Comparative assessment of proximate composition,physicochemical parameters,fatty acid profile and mineral content in farmed and wild rainbow trout (Oncorhynchus mykiss)

This study was conducted to determine differences between farmed and wild rainbow trout in terms of proximate and fatty acid composition, physicochemical parameters and mineral content. Fat content of farmed fish fillets was higher, while moisture content was lower than wild fish. However, wild fish had higher pH value and water‐holding capacity comparing to farmed fish. The muscle lipids of farmed fish contained higher proportions of 20:0, 18:1n‐9 and 20:1n‐9; and lower proportions of 18:2n‐6, 20:2cis, 18:3n‐3, 20:3n‐6, 20:4n‐6, 20:5n‐3 and 22:6n‐3 fatty acids than wild fish. The percentage of total saturated fatty acids (SFAs) was similar in both fish. Total polyunsaturated fatty acids (PUFAs), n‐3 PUFAs and n‐3/n‐6 PUFAs ratio were higher in the wild fish comparing to farmed fish, whereas its total monounsaturated fatty acids (MUFAs) and n‐6 PUFAs contents were lower. Among the seventeen minerals analysed in fish flesh, differences existed between farmed and wild rainbow trout in Ca and Fe contents. Moreover, toxic trace minerals (As, Cd, Pb and Hg) were all present in amounts below their toxic levels. The differences observed between farmed and wild fish may be attributed to the diet constituents and environmental conditions of the fish.     

Comparative study of proximate composition and amino acid in farmed and wild Pseudobagrus ussuriensis muscles

The proximate composition and amino acid compositions of the muscle of wild and farmed Pseudobagrus ussuriensis were compared. The lipid content of the farmed fish was significantly higher, while moisture content was significantly lower, than those of the wild fish. Pseudobagrus ussuriensis protein has a well‐balanced amino acid composition. The percentages of total amino acids, essential amino acids, nonessential amino acids and delicious amino acids were significantly higher in the wild than those in farmed fish. The ratios of W_EAA to W_TAA (42.78%–43.02%) and W_EAA to W_NEAA (85.52%–87.74%) were comparable to the reference values of 40% and above 60% recommended by FAO/WHO. According to the amino acid scores, methionine would have been described as the first limiting amino acid, and Lys had the highest score for the protein in both wild and farmed Pseudobagrus ussuriensis. This study shows that Pseudobagrus ussuriensis under investigation have high nutritional qualities and are good protein resources.     

Kigelia africana seed: proximate,mineral, vitamin E,fibre, amino acid and fatty acid composition

Research reports on the ethnomedical and pharmacological potential of Kigelia africana extracts. In this study, the nutritional potential of K. africana seed and seed oil was evaluated by chemical analyses. Organic matter and ash constituted 915.23 ± 7.98 g kg^?1 DM and 49.05 ± 4.55 g kg^?1 DM of the seed mass, respectively. Oil constituted 492.2 g kg^?1 DM of the seed mass with oleic acid, linoleic acid and α‐linolenic acid constituting 17.6%, 12.9% and 54.3%, respectively, of the seed oil. Vitamin E concentration was 0.94 ± 0.25 μg g^?1. Crude protein was 357.35 ± 3.39 g kg^?1 DM. Arginine (6.14 ± 0.31 g per 100 g) as the most abundant amino acid and hydroxyproline (0.11 ± 0.06 g per 100 g) the least. Phosphorus (1123.2 mg per 100 g) and calcium (56.1 mg per 100 g) were, respectively, the most and least abundant minerals. Gross energy was 29.6 ± 0.06 MJ kg^?1. Kigelia africana seeds could be exploited as nutrient‐dense dietary supplement rich in protein, oleic acid and essential fatty acids.     

Effects of cooking methods on the proximate,mineral and fatty acid composition of European eel (Anguilla anguilla)

The influence of microwave cooking and traditional cooking methods such as baking, grilling and frying on the nutritional composition of eels (Anguilla anguilla) was studied. All methods reduced moisture and increased the protein and fat content. Although the potassium and sodium content of fish cooked by different methods decreased significantly (P = 0.000), the calcium and magnesium content increased. The zinc content of the fish was not affected by cooking. The manganese and iron content significantly increased only in fried fish. The copper content was increased by grilling and microwave cooking. The proportion of saturated fatty acids and monounsaturated fatty acids in cooked fish decreased. Omega‐3 polyunsaturated fatty acids were increased by all cooking methods. The grilling and microwave‐cooking methods were the most suitable considering the n3/n6 ratio and eicosapentaenoic acid levels. The increase in the docosahexaenoic acid level of fried fish enhanced its nutritional value.     

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.     

Fatty acid profile and proximate composition of Pacific mullet (Mugil so‐iuy) caught in the Black Sea

This study demonstrates proximate composition and fatty acid profile of Pacific mullet caught in Turkey. The highest moisture and protein contents were observed with muscle tissues as 83.74 and 10.52%, while the highest fat and ash contents were attributed to female gonads as 11.80 and 0.94%, respectively, with a significant variation amongst months (P < 0.05). Significant variation (P < 0.05) usually occurred amongst months within the same sex for total saturated fatty acids ( ∑ SFA), monosaturated fatty acids ( ∑ MUFA), polyunsaturated fatty acids ( ∑ PUFA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in muscle, although overall mean values between sexes were not found significant. Except for EPA, no variation observed for gonads while significant changes occurred (P < 0.05) with liver samples amongst months. Overall total values of ∑ SFA, ∑ MUFA, ∑ PUFA, DHA and EPA in muscle samples were 29.59, 29.26, 18.06 and 4.48%, respectively, while in gonads ranged as 30.26–33.23%, 35.17–37.47%, 11.87–14.88%, 4.38–5.34% and 3.02–5.02%. These FAs were 21.57–33.11%, 32.89–50.96%, 14.78–20.08%, 0.89–9.94% and 5.85–9.54% for liver, respectively. The results of this study showed that muscle and gonads of Pacific mullet were rich in n‐3 PUFA, especially, EPA, DHA, increasing the value of this species for human consumption.     

Seasonal changes in the proximate chemical compositions and fatty acids of chub mackerel (Scomber japonicus) and horse mackerel (Trachurus trachurus) from the north eastern Mediterranean Sea

The effects of seasonal variations on the proximate chemical compositions and fatty acid profiles of chub mackerel (Scomber japonicus) and horse mackerel (Trachurus trachurus) captured in the north‐eastern Mediterranean Sea were investigated. Protein fluctuations were observed in two species for all seasons. The lipid content of both species was lower in winter than in autumn and spring. In all seasons, the major fatty acids in both species were observed to be palmitic acid (16:0), stearic acid (18:0), oleic acid (18:1 ω9), eicosapentaenoic acid (20:5 ω3) and docosahexaenoic acid (20:6 ω3). Chub mackerel and horse mackerel exhibited seasonal fluctuations in their fatty acid contents. The fatty acid profile of the two species had a higher degree of unsaturation during winter. The levels of EPA in chub mackerel in winter, spring and autumn were 5.96%, 4.86% and 4.33%, respectively, while those of DHA were 24.94%, 18.75% and 17.12%, respectively. The levels of EPA in horse mackerel in winter, spring and autumn were 5.42%, 5.03% and 4.86%, respectively, while those of DHA were 14.96%, 13.31% and 11.10%, respectively. The PUFA (polyunsaturated fatty acids) values and ω3/ω6 ratios in the two species were highest in winter. The results indicate that chub mackerel and horse mackerel captured in the north‐eastern Mediterranean Sea, which are among the most important fish in Turkey and of international commercial value, are a good source of nutrition for human consumption in terms of their proximate chemical composition and fatty acids.     

The chemical composition of different edible locations (central and edge muscles) of flat fish (Lepidorhombus whiffiagonis)

The chemical composition of the different edible locations (central and edge muscles) of a flat fish (megrim, Lepidorhombus whiffiagonis) was comparatively analysed at both body sides. Higher moisture and lower lipid contents were obtained in central muscles than in edge ones. Edge sites showed higher triacylglycerols and sterols contents and lower mean phospholipids values than central muscles. A higher α‐tocopherol presence was observed in the lipid fraction of central muscles than in the edge ones. For both fish sides, fatty acid (FA) analysis showed lower monounsaturated FA and higher polyunsaturated FA contents and ω3/ω6 ratios in central muscles. Presence of essential elements (Co, Cu, Mn, Se, Zn) did not provide differences among sites considered. Concerning toxic elements, As content showed greater levels in central muscles than in their corresponding edge sites for both fish sides, upper zones showed higher mean scores in As, Cd, Cr, Hg, Ni, Pb and V.     

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.     

Effect of genotype and environment on fatty acid composition of Lupinus albus L. seed

Six cultivars of Lupinus albus L. (white lupin) were grown in two subcontinental-climate environments and one Mediterranean-climate environment in Italy, to assess the influence of genotypic (G) and genotype × environment (GE) interaction effects on grain yield and grain content of oil, total saturated fatty acids (FAs), polyunsaturated FAs, monounsaturated FAs, and ω−3/ω−6 FA ratio. The variance of genotypic effects was much larger than the GE interaction variance for all variables, except for grain yield, indicating that oil content and FA composition of different varieties can be assessed reliably in just a few test environments. Gas-chromatographic analyses highlighted that linoleic acid and α-linolenic acid were in the range 1.76–4.76 mg/g flour (7.79–15.81% of total FAs) and 1.17–3.14 mg/g flour (5.40–10.36% of total FAs), respectively. As a consequence, the analysed lupin seeds exhibited a very favourable ω−3/ω−6 FA ratio, ranging from 0.49 to 0.79.     

Seasonal variation in the fatty acid composition of three Mediterranean fish – sardine (Sardina pilchardus), anchovy (Engraulis encrasicholus) and picarel (Spicara smaris)

The total fat contents and the fatty acid compositions of three common Mediterranean fish, namely sardine (Sardina pilchardus), anchovy (Engraulis encrasicholus) and picarel (Spicara smaris) were determined at bimonthly intervals for a one-year period. The purpose of this work was to study the seasonal variation of the fatty acids in the three fish that are some of the best sources of n − 3 fatty acids. The fat and fatty acid content of the investigated fish species show a significant seasonal dependency. Two of the fish (anchovy and picarel) have the highest fat content during the late winter – spring period. On the other hand, sardine shows the highest fat concentrations during the spring-early summer period. The fish that showed the highest variation in fatty acid composition was the anchovy. The sardine was found to be the best source of n − 3 fatty acids during the one-year period (35.35 g/100 g fatty acids). Finally the picarel had the highest oleic acid content (on average, 13.89/100 g fatty acids).     

Lipids classes, fatty acids and carotenes of the leaves of six edible wild plants

 α-Linolenic acid and unusual fatty acids of the ω3 and ω6 series play an important role in the modulation of human metabolism. The presence of these acids in the leaves of several edible wild plants has recently been reported. In this study, six edible wild species were selected in order to establish the fatty acid compositions in their leaf lipids. Thus, young leaves from Amaranthus viridis L.(blet), Chenopodium album L. (goosefoot), Crithmum maritimum L. (rock samphire), Plantago major L. (plantain), Portulaca oleracea L. (purslane) and Verbena officinalis L. (vervain) yielded 1.50, 2.20, 3.02, 1.46, 3.81, and 2.28 g of lipids per 100 g dry plant material. Silica gel chromatography yielded 0.64 g (Plantago major) to 2.19 g (Crithmum maritimum) neutral lipids, 0.37 g (Plantago major) to 1.60 g (Portulaca oleracea) glycolipids, and 0.26 g (Crithmum maritimum) to 0.57 g (Verbena officinalis) phospholipids per 100 g (dry weight). Gas chromatography (GC) showed the major fatty acids to be 18 : 3ω3, 18 : 2ω6 and 16 : 0 in all fractions, with high concentrations of 18 : 3ω3 in the glycolipid fraction. GC-mass spectrometric analyses did not reveal the presence of unusual fatty acids. Carotenes were found in high concentrations, ranging from 30.5 mg/100 g (Chenopodium album) to 89.2 mg/100 g (Portulaca oleracea). The analyzed plants are rich sources of essential fatty acids (18 : 2ω6 and 18 : 3ω3) and also of carotenes. Received: 29 October 1998     

Proximate,mineral, amino acid,fatty acid,vitamin E,phytate phosphate and fibre composition of Mimusops zeyheri (Red Milkwood) seed

Mimusops zeyheri, an indigenous tree widely distributed in sub‐Saharan Africa, provides edible fruit. Research on the tree has focused on fruit pulp composition and uses. This study evaluated the nutritional potential of M. zeyheri seed by determining the proximate, fibre and phytate‐phosphate content, the amino acid and fatty acid profiles and vitamin E content of the seed. Dry matter, organic matter, crude protein, ether extract and ash constituted 91.1%, 88.3%, 9.3%, 25.6% and 2.8% of the seed mass respectively. Glutamic acid (1.29 g per 100 g) was the most abundant amino acid. Lysine and phenylalanine were low. Calcium (587.4 mg per 100 g) was the most concentrated macro‐mineral assayed. Gross energy value was 24.34 MJ kg^?1. Lipid yield was 21.3%. Oleic acid was the most abundant fatty acid. Vitamin E concentration was about 2 μg g^?1. Phytate‐phosphate content was 0.03%. Neutral detergent fibre and acid detergent fibre constituted 33.2% and 15.3% respectively. M. zeyheri seed could be exploited as a dietary energy supplement and an oil source rich in oleic acid.     

Seasonal changes of fatty acids of cuttlefish Sepia officinalis L. (Mollusca: Cephalopoda) in the north eastern Mediterranean sea

The total lipids and seasonal variations in the fatty acids of the mantle of cuttlefish (Sepia officinalis) captured in the north eastern Mediterranean were investigated and the mantle was found to be a good source of polyunsaturated fatty acids (ω3 PUFAs, in particular). In all seasons, the major fatty acids in the cuttlefish mantle were observed to be palmitic acid (16:0), stearic acid (18:0), eicosapentaenoic acid (EPA, 20:5ω3) and docosahexaenoic acid (DHA, 22:6ω3). A comparison of the saturated fatty acid (29.5–36.8%), monounsaturated fatty acids (7.81–9.84%) and polyunsaturated fatty acids (43.7–49.6%) of the cuttlefish mantle revealed that polyunsaturated fatty acids (PUFA) constituted the highest proportion. The levels of DHA in the cuttlefish mantle in autumn, winter, spring and summer were 27.6%, 28.5%, 29.5% and 23.9%, while those of EPA were 16.8%, 15.4%, 14.7% and 13.9%, respectively.     

Effect of defatting and decortication on distribution of fatty acids,phenolic and antioxidant compounds in sorghum (Sorghum bicolor) bran fractions

Sorghum bran components could be a potential source of nutrients and phytochemicals for industrial applications. The effect of defatting with hexane and different degrees of decortication on distribution of fatty acids, phenolic compounds, colour (L, a and b) and antioxidant activity (DPPH) of red (RS) and white (WS) sorghums was studied. The decortication process was carried out at time intervals of 1–6 min. Defatted and nondefatted fractions were analysed. The content of polyunsaturated fatty acids (PUFA) was higher than monounsaturated fatty acids (MUFA); the content of MUFA was higher than saturated fatty acids (SFA). Linoleic, oleic and palmitic acids predominated in all fractions. Significant differences in the content of palmitic and linolenic acids between sorghums were found. RS had higher content of palmitic, and WS was higher in linoleic acid. Defatted samples contained lower amounts of phenolic compounds and higher antioxidant activities, than nondefatted samples. RS was a better source of total phenolic compounds and antioxidant activity compared with WS, but WS presented a more suitable profile of fatty acids. In conclusion, fractions of both types of sorghums can be used in cereal‐based products to enhance their phytochemical profile.     

The fatty acid composition of the oil from Lupinus albus cv. Luxe as affected by environmental and agricultural factors

There is a growing interest in white lupin (Lupinus albus L.) seed for food or feed, favoured by the availability of well-performing varieties with low content of alkaloids. The objective of this study was to assess the influence of the environmental and agricultural factors on the content and fatty acid composition of lupin oil. The investigation was performed on the sweet variety Luxe grown in three Italian locations (one continental and two Mediterranean) and 13 environments in total. Statistical analyses (analysis of variance and principal component analysis) indicated that oil content and composition of fatty acids were affected largely by the growing location. Mediterranean sites tended to lower crop yield, but to increase oil content and absolute α-linolenic acid content compared to the continental location; large variation occurred also between the Mediterranean sites. The α-linolenic acid content ranged from 1.41 to 3.24 mg/g flour, highlighting the possible value of white lupin in order to reach the recommended daily intake of this fatty acid. The observed ω-3/ω-6 ratio, ranging from 0.45 to 0.63, was much higher than that of most vegetable oils.     

Effects of feeding flaxseed or sunflower-seed in high-forage diets on beef production,quality and fatty acid composition

Yearling steers were fed 70:30 forage:concentrate diets for 205 d, with either grass hay (GH) or red clover silage (RC) as the forage source, and concentrates containing either sunflower-seed (SS) or flaxseed (FS), each providing 5.4% oil to diets. Feeding diets containing SS versus FS significantly improved growth and carcass attributes (P < 0.05), significantly reduced meat off-flavor intensity (P < 0.05), and significantly increased intramuscular proportions of vaccenic (t11-18:1), rumenic (c9,t11-CLA) and n − 6 fatty acids (FA, P < 0.05). Feeding diets containing FS versus SS produced significantly darker and redder meat with greater proportions of atypical dienes (P < 0.05). A significant forage × oilseed type interaction (P < 0.05) was found for n − 3 FA, α-linolenic acid, and conjugated linolenic acid, with their greatest intramuscular proportions found when feeding the RC-FS diet. Feeding GH versus RC also significantly improved growth and carcass attributes, sensory tenderness (P < 0.05) and significantly influenced intramuscular FA composition (P < 0.05), but overall, forage effects on FA profiles were limited compared to effects of oilseed.