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1.
Chemical composition and fatty acid profiles were determined in Caiman yacare meat originating from the neck and tail cuts of animals raised in the wild (n = 6) or in captivity (n = 6), slaughtered at a live weight of approximately 6 kg. All experimental methods were approved by the appropriate environmental protection agencies. Most chemical components were affected by the origin-cut interaction, with the tail cut of wild animals having the highest amount of intramuscular fat (19.2% of DM) and the lowest of moisture (71.8%) and protein (77.0% of DM). Yacare meat had low amounts of SFA (35.1%), which were similar (P > 0.05) in the cuts and origins studied. The total amount of PUFA was higher (P < 0.05) in wild (31.0%) than in captive animals (23.6%), and n − 3 fatty acids had means of about 5% and 2% for the same groups, respectively (P < 0.05). In general, the FA profile of intramuscular fat in yacare meat had a desirable PUFA/SFA ratio above 0.4.  相似文献   

2.
Fructose, glucose and sucrose, as the major soluble sugars and citric and malic acids, as the major organic acids, were identified and determined in kale (Brassica oleraceae L. var. acephala DC., black cabbage) leaves. Fructose was the predominant sugar (2011 mg 100 g−1 dry wt) identified, followed by glucose (1056 mg 100 g−1 dry wt) and sucrose (894 mg 100 g−1 dry wt). The contents of citric and malic acids were at 2213 and 151 mg 100 g−1 dry wt in the leaves. The 16:0, 18:2n − 6 and 18:3n − 3 fatty acids were the most abundant fatty acids in the leaves. Considering the level of these fatty acids, 18:3n − 3 was found to be the highest (85.3 μg g−1 dry wt), contributing 54.0% of the total fatty acid content. Linoleic acid (18:2n − 6), being the second most abundant fatty acid was present at 18.6 μg g−1 dry wt, contributing 11.8% of the total fatty acid content. In the seed oil of kale, 22:1n − 9 was the most abundant fatty acid (4198 μg g−1 dry wt, 45.7%), with 18:2n − 6 (1199 μg g−1 dry wt, 12.3%) and 18:1n − 9 (1408 μg g−1 dry wt, 14.8%) being the second next most abundant fatty acids. The most abundant amino acid was glutamic acid (Glu) which was present at 33.2 mg g−1 dry wt. Aspartic acid, which was the second most abundant amino acid, was present at 27.6 mg g−1 dry wt and accounted for 10.2% of the total amino acid content of kale leaf. The amino acid content was assessed by comparing the percentages of the essential amino acids in kale leaf versus those of a World Health Organization (WHO) standard protein. The protein of kale leaf compares well with that of the WHO standard. Only one amino acid, lysine, had a score that fell below 100%; the lysine score of kale leaf was 95%. This study attempts to contribute to knowledge of the nutritional properties of the plant. These results may be useful for the evaluation of dietary information.  相似文献   

3.
Significant enrichment of dry fermented sausages in n−3 polyunsaturated fatty acids (PUFA) was achieved by incorporating algae oil from Schizochytrium sp. into an emulsion that partially substituted pork backfat from the traditional formulation. Two different levels of substitution were initially tested, both including BHA and BHT as antioxidants: (15% and 25%). A triangular test showed that products with 25% substitution were not sensorially acceptable. Sausages with 15% substitution supplied 1.30 g/100 g product of docosahexaenoic acid (DHA), with an interesting n−6/n−3 ratio of 2.62. No signs of oxidation were detected at the end of the ripening process, with low values of TBARs (<0.2 mg/kg), peroxides (<2 meq O2/kg fat) and volatile aldehydes. Storage of these sausages under vacuum during 30 days totally guaranteed their stability, whereas after 90 days certain degree of oxidation was detected, only by means of aldehydes analysis. Hexanal, nonanal and dienals increased, whereas no increment in TBARs or peroxides were observed. Aerobical storage of these sausages was not viable due to a high oxidation susceptibility of the new formulation, despite the use of antioxidants.  相似文献   

4.
An extracellular lipase purified from Pseudomonas fluorescens MTCC 2421 was used to enrich sardine oil triglycerides with eicosapentaenoic acid (20:5 n−3) and linolenic acid (18:3 n−3) to 35.28% and 8.25%, respectively, after 6 h of hydrolysis. The corresponding n−6 fatty acids (18:2 n−6 and 20:4 n−6) exhibit a reduction (54.93% and 50%, respectively). Structure–bioactivity relationship analyses revealed that the lower hydrophobic (log P values) constants of 18:3 n−3 and 20:5 n−3 (5.65 and 5.85, respectively) result in their higher hydrolytic resistance towards lipase, leading to their enrichment in the triglyceride fraction after lipase-catalysed hydrolysis. Lipase-catalysed hydrolysis of sardine oil for 6 h followed by urea fractionation at 4 °C with methanol provided free fatty acids containing 42.50% 20:5 n−3 and 10.31% 18:3 n−3, respectively. Argentation neutral alumina column chromatography, using n-hexane/ethylacetate (2:1, v/v) resulted in 20:5 n−3 of high purity (83.62%), while 18:3 n−3 was found to be eluted with n-hexane/dichloromethane (4:1, v/v) as eluting solvent with a final purity of 75.31%.  相似文献   

5.
This study addressed determinations of the fatty acid profile of muscle, liver and mesenteric fat in European perch originating from natural aquifers and from intensive rearing in a closed circuit on an artificial feed mixture. The qualitative composition of fatty acids was identical in both groups of perch, except for 16:4 acid identified exclusively in the reared perch. The study demonstrated equal concentrations of saturated (SFA) and unsaturated (UFA) fatty acids in muscles, liver and mesenteric fat of both groups of perch. The wild fish, however, were characterised by lower concentrations of monoenoic (MUFA) and higher concentrations of polyenoic (PUFA) fatty acids. Analyses also demonstrated similar contents of n − 3 PUFA in muscles and their diversified concentrations in liver and mesenteric fat (higher in the wild fish), as well as a higher content of n − 6 PUFA in all samples. The lower content of MUFA in the wild perch was mainly due to lower concentrations of cis18:1 n − 9 and 20:1 n − 9, whereas the higher content of n − 3 PUFA was due to a higher concentration of DHA, and the higher content of n − 6 PUFA was due to a higher concentration of arachidonic acid (AA). The biggest differences between wild and reared perch were detected for AA. The wild and reared perch were also found to differ in the n − 3/n − 6 ratio (higher in the reared fish) and to have similar values for atherogenic index (AI) (except for liver and mesenteric fat) and thrombogenicity index (TI).  相似文献   

6.
The effectiveness of increasing CLA in pork products through animal dietary supplementation or direct addition in the product formulation has been studied, and the effect of grilling on dry matter and fat contents and fatty acid composition has been analysed. Sausages made with meat and back fat from pigs with CLA dietary supplementation had the highest saturated fatty acid content. Sausages from dietary supplementation and direct addition had CLA levels between 6% and 7% of total fatty acids. Moisture and fat contents decreased and increased respectively after cooking for the three sausage types (control, dietary supplementation, direct addition). Grilling had little effect on fatty acid levels, especially for sausages with direct addition in the product formulation. In general, saturated fatty acids increased and poly-unsaturated fatty acids decreased due to the increase of C16:0 and to the decrease of C18:2 n − 6c and C18:3 n − 3 fatty acids. Added CLA, both from animal dietary supplementation or direct addition, remained at similar levels in cooked sausages to those found in raw sausages.  相似文献   

7.
The present study was conducted to evaluate the ability of horse fat produced in Uruguay, compared with other lipid sources supplemented in the diet of laying hens, to modify the lipid composition and the n − 6/n − 3 fatty acid ratio of the produced eggs. For this purpose, 60 laying hens (Gallus domesticus) were fed for 30 days with five experimental diets (12 hens/diet) containing 3% sunflower oil (SO), rice oil (RO), beef tallow (BT), pressed-fat (PF), obtained by pressing fat from bovine viscera, and horse fat (HF) obtained from horse bone medulla. Throughout the trial, feeding rate, shell index, weight and total lipid contents of eggs, were not affected by the different diets. Feeding on the SO and RO diets significantly increased the amount of linoleic acid of the egg, although it was lower in the RO than in the SO eggs. Diet BT did not affect the saturated fatty acid content of the yolks. The diets with animal fats containing 18:3n − 3 (diets PF and HF), resulted in a significant increase in the n − 3 fatty acid contents of the eggs, through an increase of linolenic (18:3n − 3) and docosahexaenoic acid (DHA, 22:6n − 3) contents. Eggs from hens fed the HF diet showed increased linolenic acid (46 mg/yolk) and DHA (71 mg/yolk, 1.7% of total fatty acids) contents. These levels were obtained after two weeks of feeding. Moreover, the fatty acid profiles of eggs from treatment HF were not significantly affected by thermal treatment of the yolks. In conclusion, the fat from horse bone medulla, as produced in Uruguay, can be considered as a suitable lipid source for diets of laying hens, to modify the nutritional composition of the eggs in n − 3 PUFA content, especially DHA, and consequently, the n − 6/n − 3 fatty acid ratio.  相似文献   

8.
Chinese mitten crab (Eriocheir sinensis) was analyzed for proximate composition, minerals, amino acids and fatty acid composition, and also evaluated for nutritional quality. The yields of crab meat and edible viscera were 24.2% and 9.2%, respectively. The crab meat contained 18.9% crude protein. About 80% of the protein resided in the crab meat portion, while about 90% of the fat was in the viscera. Chinese mitten crab was an excellent source of minerals, particularly zinc, iron, copper and phosphorus. The crab protein contained high amounts of glutamic acid (151 mg/g), aspartic acid (99 mg/g), arginine (99 mg/g), lysine (81 mg/g) and leucine (77 mg/g), and it was a high quality protein with well-balanced essential amino acid compositions. Twenty six fatty acids were found in the crab oil. The monounsaturated fatty acids were predominant with a percentage of 49.8. Oleic acid (18:1) was the dominant fatty acid, followed by palmitoleic acid (16:1), palmitic acid (16:0) and linoleic acid (18:2n − 6); and the percentages were 31.0, 14.3, 14.2 and 11.9, respectively. The ratio of n − 6/n − 3 polyunsaturated fatty acids (PUFAs) was 2.2, and this is a n − 3 PUFA-rich food. In short, the results showed that Chinese mitten crab is a nutritious food.  相似文献   

9.
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).  相似文献   

10.
Dutch-style fermented sausages were manufactured with 15% and 30% pork back-fat substitution by pure or commercial encapsulated fish oil, either added as such or as pre-emulsified mixture with soy protein isolate. Adding commercial encapsulated fish oil was the most important factor influencing the chemical composition. The fat content was not significantly different between products (p > 0.05). The n−6/n−3 ratio decreased from 8.49 in controls to 0.90-2.47 in modified products. Lipid oxidation parameters (propanal and hexanal) showed much higher values for sausages with pure fish oil than for products with encapsulated oil. For the latter, lipid oxidation was similar to controls. Products with encapsulated or pre-emulsified oil were significantly firmer than products from other treatments in physical and sensory analysis (p < 0.05). Overall, it is technologically feasible to enrich dry fermented sausages with n−3 fatty acids from fish oil and the application of commercial encapsulated fish oil seems to be the best in retaining overall quality.  相似文献   

11.
An extracellular lipase derived from Bacillus circulans, isolated from marine macroalga, Turbinaraia conoides, was used to prepare n-3 polyunsaturated fatty acid (PUFA) concentrates from sardine oil triglycerides. The enzyme was purified 132-fold with specific activity of 386 LU/mg. The purified lipase was able to enrich sardine oil with 37.7 ± 1.98% 20:5n-3 and 5.11 ± 0.14% 18:3n-3 in the triglyceride fraction after 3 h of hydrolysis. Lower hydrophobic constants of n-3 fatty acids (18:3n-3logP = 5.65; 20:5n-3logP = 5.85, respectively) than n-6 (20:4n-6logP = 6.16) resulted in higher hydrolytic resistance of the former toward lipase, leading to their enrichment in the triglyceride fraction. Lipase-catalysed hydrolysis of sardine oil for 3 h, followed by urea complexation, provided free fatty acids containing 51.3 ± 4.65% 20:5n-3. The purified methyl ester of 20:5n-3 (68.29 ± 2.15%) from the urea concentrate was attained by chromatography on argentated neutral alumina.  相似文献   

12.
The effects of sex, slaughtered age (9 vs. 12 months) and livestock production system (freedom extensive system vs. semi extensive system) of “Galician Mountain” foals breed on the fatty acid composition were studied. The sex and slaughtered age of the animals had no statistical significance in the intramuscular fatty acids. Furthermore, the livestock production system showed differences in the fatty acid profiles from the Longissimus dorsi. The feeding system showed significant differences in PUFA content (P < 0.001) higher in freedom extensive production system that semi extensive system, whereas MUFA content was significantly (P < 0.001) higher in semi extensive system. This major PUFA content in freedom extensive production showed a significant (r = 0.70, P < 0.01) correlation with C18:3n− 3 content and can be attributed to their eaten only pasture until slaughtered. The higher MUFA contents (P < 0.001) observed for semi extensive production system foals were very significant (r = 0.98, p < 0.01) correlated with C18:1cis−9 content and less significant (r = 0.81, P < 0.01) correlated with C16:1cis−9 content. In addition, the data reinforced the evidence that foals from extensive production system on wood pasture have a higher nutritional quality (mainly due to the higher levels of n−3 PUFA) when compared to concentrate-fed foals, as a result of the beneficial effects of grass on meat fatty acid profiles.  相似文献   

13.
Carp viscera oil can be obtained by both ensilage and fishmeal processes. This study examined the refinement of carp (Cyprinus carpio) oils obtained by both processes, and compared crude, neutralised, bleached, winterised and deodorised oils’ characteristics and lipid profiles. Refined oils obtained by the two processes did not present significant difference (> 0.05) for Lovibond colour, free fatty acids, and thiobarbituric acid values. The major fatty acids identified in the carp crude, bleached and refined oils were oleic, palmitic, palmitoleic, linoleic and linolenic, constituting approximately 69.6% of the total fatty acids of the oils. The n − 3/n − 6 ratio was approximately 1.05 for refined oil. Therefore, carp viscera refined oil can be considered a rich source of essential fatty acids of the n − 3 and n − 6 series.  相似文献   

14.
Fatty acid content and sensory characteristics of meat from light lambs fed three diets supplemented with different sources of n−3 fatty acids (fish oil, extruded linseed and extruded linseed plus microalgae) and a control diet during refrigerated storage have been studied. The meat from lambs fed linseed diets had the highest levels of C18:3 n−3, while animals fed fish oil had the highest long-chain n−3 polyunsaturated fatty acids (PUFA). Thus, 100 g of meat from lamb fed the fish oil diet provided 183 mg of long-chain n−3 PUFA, representing 40% of the daily recommended intake. The levels of n−3, n−6 and long-chain n−3 PUFA decreased during a 7-day storage period. The meat from lambs fed the fish oil diet had high scores of fish odour and flavour and rancid odour and flavour and the lowest overall liking. Rancid odour and flavour increased after storage, mainly in supplemented groups.  相似文献   

15.
In this study the effects of soybean and linseed oils on chemical and sensory characteristics of fillets were evaluated in the freshwater fish tench (Tinca tinca L.). Five experimental diets, differing only in the relative amount of soybean and linseed oil, were formulated and the experiment was conducted on 360 sub-adult tench for 12 weeks. The fatty acid composition of muscle reflected that of the diets and significant correlations were observed. Diets containing higher amounts of n − 6 fatty acids were responsible for an increased level of n − 6 fatty acids in the fish flesh. Consequently, an increase in the relative amount of n − 6-derived volatile aldehydes was also observed. These latter compounds are generally reported to contribute negatively to the general aroma of fish muscle and, consistently, the results of the sensory analysis showed a high value for the “off-flavour” attribute for fish fed the diet containing only n − 6-rich soybean oil.  相似文献   

16.
The composition of three porcine muscles (Longissimus thoracis: LT, Semitendinosus: ST, Masseter: MS) was characterized and its link with muscle quality was evaluated. The LT muscle had a higher content of tyrosine, tryptophan, and carbohydrates and a lower content of vitamin E and haem iron than the MS muscle, while the ST had similar composition to MS but a lower content of haem iron. Large differences between muscles were observed in relative amounts of most of the major fatty acids. The LT muscle had higher saturated fatty acids (SFA) and n− 6:n− 3 fatty acid ratio, and lower polyunsaturated fatty acids (PUFA), PUFA:SFA ratio, unsaturation index and average fatty acid chain length than the ST and MS muscles. Muscle pH, redness and chroma were positively correlated with vitamin E and unsaturated lipids and negatively correlated with tyrosine, tryptophan, carbohydrates and saturated lipids, whereas muscle lightness and expressible juice showed similar correlations but an opposite sign with these variables.  相似文献   

17.
This study investigated lipid oxidation in spaghetti enriched in long chain n−3 polyunsaturated fatty acids (LC n−3 PUFA) by the addition to semolina of an integrator containing eicosapentaenoic acid and docosahexaenoic acid. Two oxidative parameters were evaluated: peroxide value (PV), to assess primary oxidation and oxidised fatty acids to quantify secondary oxidation products. Functional spaghetti had a shelf life comparable to control pasta. LC n−3 PUFA were not significantly implicated in the onset of oxidation in spaghetti stored under daylight and accelerated oxidation in a laboratory heater. Storage decidedly affected shelf life: PV in functional spaghetti increased from 7.1 to 43.4 meq O2/kg of fat under light exposure over 12 months, and from 7.1 to 16.2 meq O2/kg under accelerated ageing at 55 °C for 27 days, reproducing about 18 months at room temperature. Oxidised fatty acids increased in fortified spaghetti from 4.8 to 13.8 g/100 g of fat under light exposure over 12 months and from 4.8 to 7.8 g/100 g of fat at 55 °C in 27 days. The high sensitivity of spectrophotometric and chromatographic analytical methods permitted the evaluation of primary and secondary oxidative derivatives in small amounts of fat.  相似文献   

18.
Nutritional quality parameters (proximate and mineral composition, contents of glycogen, fatty acids, cholesterol, plant sterols, fat-soluble vitamins, carotenes) and ecophysiological and commercial quality indicators (Condition Index, percent content of meat and intervalvar fluid) of the striped venus clam, Chamelea gallina, from the central Adriatic coast of Italy were studied at seasonal intervals over a 1-year period. Contents of protein (8.55–10.7 g/100 g), total lipid (0.73–1.59 g/100 g), glycogen (2.25–4.96 g/100 g) and non-protein nitrogen (0.54–0.78 g/100 g) varied significantly during the year, reaching the highest values in winter, in coincidence with a peak of Condition Index. Gas chromatography of total lipids showed high percentages of n − 3 polyunsaturated fatty acids (33.7–41.9% of total fatty acids), in particular eicosapentaenoic (8.16–20.0% of total fatty acids) and docosahexaenoic acids (12.5–20.3% of total fatty acids) and low levels of total n − 6 polyunsaturated fatty acids (3.61–7.87% of total fatty acids). HPLC analysis of the unsaponifiable lipids showed low levels of cholesterol, the dominant sterol (28.3–34.2 mg/ 100 g), and variable amounts of plant sterols (stigmasterol + campesterol, β-sitosterol, fucosterol + brassicasterol), α-tocopherol and carotenes.  相似文献   

19.
The effects of using α-linolenic and α-tocopherol acid-enriched pork on the fatty acids and sensory characteristics of Spanish dry-cured loins were investigated. For the study, five batches of Spanish dry-cured loins were manufactured using pork loin enriched in polyunsaturated n − 3 fatty acids and α-tocopherol. Tissues were obtained from pigs fed on diets with the same ingredients, except for the oil source which corresponded to: [sunflower (C), linseed (L) and linseed and olive (1/1, w/w) (LO)] and two different amounts of α-tocopheryl acetate [20 (C, L and LO) or 200 (LOE and LE) mg/kg diet]. Dry-cured loins with polyunsaturated fatty acid n6/n3 ratios below 4 were obtained from linseed and linseed/olive oil-enriched batches. Dry-cured loin manufactured with pork from animals fed on diets enriched only with linseed oil presented the worst sensory characteristics and higher TBAR values than did dry-cured loins from animals fed on diets enriched with linseed and olive oil and linseed oil plus tocopheryl acetate.  相似文献   

20.
Truffle, belonging to Tuber genera, is a nutritious and sterol-rich edible fungus, and sterol is a potential health beneficial compound. A comparison of Tuber sterol composition indicates that the total sterol contents in the fermentation mycelia (i.e., 10.5 mg g−1) (n = 3) were approximately 3.2-5.6 times higher than that of the fruiting bodies (< 0.05) with the addition of soybean flour into the basal fermentation media. Moreover, the phytosterol profile of fermentation mycelia could be significantly improved by adding soybean flour into the fermentation media. After the addition of soybean flour, stigmasterol and β-sitosterol appeared in the fermentation mycelia and the contents of total phytosterols (2279 μg g−1) (n = 3), brassicasterol (943 μg g−1) (n = 3), and campesterol (418 μg g−1) (n = 3) were all increased significantly (< 0.05). Moreover, the total contents of sterols and phytosterols in the fermentation mycelia cultured in the soybean media were much higher than those in the fruiting bodies (i.e., 1883-3240 and 479-1832 μg g−1, respectively) (n = 3, < 0.05). This work confirms the potentiality of Tuber fermentation mycelia as the alternative resource for its fruiting bodies from the viewpoint of sterols production.  相似文献   

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