Tuna Red Meat as a Novel Ingredient in Pet Food for Dogs

ABSTRACT

Red meat from tuna canning factory was used to develop a pet food for dogs. Feed was developed by mixing cooked, dried, and powdered red meat with cereal flours in varying proportion. The combination that gave maximum hardness for the feed was selected as optimum. The developed feed had a crude protein content of 20.2 ± 0.95% and crude fat content of 4.70 ± 0.37%. Analysis of mineral content showed that it is rich in macro minerals, including phosphorus (2843.67 ± 206 ppm), sodium (1333.54 ± 56 ppm), and calcium (400.04 ± 21 ppm). Amino acid content of the feed showed that it meets the dietary requirements of dogs in terms of threonine, methionine, histidine, lysine, arginine, and tryptophan. Polyunsaturated fatty acid content of the feed was dominated by linoleic acid, followed by DHA and EPA.     

中华圆田螺氨基酸、脂肪酸营养价值与重金属安全性评价

为分析中华圆田螺(Cipangopaludina cathayensis)肌肉营养成分及重金属污染状况,检测了中华圆田螺肌肉的常规营养成分、氨基酸、脂肪酸及部分重金属含量,采用氨基酸评分(AAS)和化学评分(CS)对肌肉氨基酸进行评价,并用单因子污染指数(I)、综合污染指数(P)和目标危险系数(THQ)对肌肉安全性进行评价。结果显示,中华圆田螺粗蛋白、水分、粗脂肪和粗灰分含量分别为13.89%、76.52%、0.57%和5.21%;肌肉中共检出16种氨基酸,总量为106.2 mg/g,包含8种人体必需氨基酸,占比36.8%,必需氨基酸指数(EAAI)为248.2,鲜味氨基酸占比48.2%。共检出19种脂肪酸,其中,8种饱和脂肪酸(SFA),占比43.8%;11种不饱和脂肪酸,占比56.2%,其中,EPA+DHA(eicosapentaenoic acid+docosahexaenoic acid)含量达到了9.77%。肌肉中铅、镉、铬和铜含量分别为0.897、0.0055、0.214和4.62 mg/kg,均符合国家卫生标准。除铅污染指数为0.897外,其余均低于0.15。综合污染指数为0.66,处于较清洁状态。综合来看,中华圆田螺具有高蛋白、低脂肪的营养特性,EPA和DHA含量丰富,无重金属暴露风险,营养价值及养殖开发价值较高。本研究探究了中华圆田螺的营养价值和安全性,可为中华圆田螺资源合理开发利用提供一定参考。     

Response of Nile tilapia (Oreochromis niloticus) to diet acidification: Effect on growth performance and feed utilization

A 12-week feeding trial was undertaken to assess growth, nutrient utilization, some hematological parameters, and proximate composition of Nile tilapia (Oreochromis niloticus) fed diets supplemented with graded levels (0.5%, 1.0%, and 1.5%) of two blends of organic acids or organic salts. Seven isonitrogenous (300 g CP kg^?1) and isocaloric (19.0 MJ gross energy kg^?1) diets were formulated. The control diet (D1) contained neither added blend of organic acids nor organic salts. Three diets (D2, D3, and D4) were supplemented with 0.5%, 1.0%, and 1.5% of malic acid + oxalic acid blend (OAB), respectively. The other three diets (D5, D6, and D7) were supplemented with 0.5%, 1.5%, and 1.5% of calcium lactate + sodium acetate blend (OSB), respectively. Fingerlings (7.05 ± 0.02 g) were randomly distributed into 21 glass aquaria (160 liter), with each aquarium holding 15 fish. At the end of the feeding trial, O. niloticus offered the control diet showed lower growth and feed utilization than all those fed the organic acids or organic salts blends supplemented diets. Fish fed the diet D3 showed the highest body weight (BW), body length (BL), weight gain (WG), specific growth rate (SGR), feed intake (FI), and the best feed conversion ratio (FCR) and protein efficiency ratio (PER). Fish fed diet supplemented by 1.5% OAB (D4) showed the highest serum protein content, while control group (D1) showed the lower level of total lipids compared with the other treatments. Fish group fed the diet supplemented with 0.5% of OSB (D5) showed the highest protein and ash contents and the lowest lipid content of the whole fish body, while the control group showed the lowest protein and the highest fat content. The present observations suggest that the growth, feed utilization, and health status of juvenile O. niloticus can be enhanced with a supplementation of 1% of OAB or OSB in the diet.     

不同规格野生黄鳍金枪鱼肌肉营养分析与评价

探究不同规格黄鳍金枪鱼(Thunnus albacares)肌肉营养成分及品质差异,实验以野捕的 3种规格黄鳍金枪鱼J1 (4.2±1.2) kg、J2 (22.5±2.5) kg和J3 (50.8±3.9) kg为研究对象,通过常规生化分析方法对金枪鱼肌肉的常规营养成分、氨基酸、脂肪酸及矿物质元素进行比较分析。结果显示,(1) J1组水分含量显著高于J2、J3组;J2、J3组粗蛋白含量显著高于J1组(P<0.05);J3组粗脂肪含量显著高于J1、J2组(P<0.05)。(2)检出19种常见氨基酸,氨基酸含量最高的为谷氨酸(3.04~ 3.25 g/100 g),必需氨基酸中含量最高的为赖氨酸(2.02~2.15 g/100 g),最低的为色氨酸(0.31~ 0.45 g/100 g)。非必需氨基酸含量J3>J2>J1 (P<0.05);必需氨基酸、呈味氨基酸含量J1组显著低于J3组(P<0.05)。依据氨基酸评分(AAS),缬氨酸为第一限制性氨基酸;以化学评分(CS)为评分标准,J1、J2组第一限制性氨基酸为色氨酸,J3组为苯丙氨酸+酪氨酸。(3)各组共检出25种脂肪酸,以多不饱和脂肪酸(PUFA)为主,含量最高的为二十二碳六烯酸(DHA),占总脂肪酸含量的37.46%~39.18%。DHA含量J3组显著高于J1、J2组;二十碳五烯酸(EPA)含量J2、J3组显著高于J1组;DHA∶EPA比值J1组显著高于J2、J3组(P<0.05)。单不饱和脂肪酸(MUFA)含量J3>J2>J1;PUFA含量J3组显著高于J1、J2组(P<0.05)。PUFA/饱和脂肪酸(SFA)、n-3系多不饱和脂肪酸/n-6系多不饱和脂肪酸(n-3/n-6)比值J2、J3组显著高于J1组(P<0.05)。h/H比值J3组显著高于J1、J2组(P<0.05)。(4) J2、J3组Na、Ca含量显著高于J1组,J1组K含量最高且显著高于J2、J3组(P<0.05)。4种重金属元素均低于食品中建议的最大允许限量,其中Fe含量最大的为J3组,且J3>J2>J1 (P<0.05);Cu含量最大的为J3组,且显著高于J1组(P<0.05)。综合分析,大规格黄鳍金枪鱼具有更好的营养质量,本研究为居民膳食的选择及黄鳍金枪鱼人工配合饲料的配制提供了科学依据。     

不同生长时期红螯螯虾肌肉和肝胰腺内氨基酸和脂肪酸变化分析

为了研究不同生长时期红螯螯虾(Cherax quadricarinatus)肌肉和肝胰腺内脂肪酸和氨基酸的动态变化,选取90 d (第二性征未发育)、140 d (第二性征发育成熟)和180 d (性腺发育成熟)的红螯螯虾,分别测定其肌肉和肝胰腺内氨基酸和脂肪酸的含量。结果显示,90 d红螯螯虾肌肉中的必需氨基酸总量显著高于其他2个时期(P<0.05);而红螯螯虾肝胰腺内必需氨基酸总量和非必需氨基酸总量均随着日龄增加而逐渐下降。比较不同生长时期肌肉中脂肪酸含量发现,随着日龄增长,饱和脂肪酸(SFA)含量呈下降趋势;而单不饱和脂肪酸(MUFA)含量呈先上升后下降的变化趋势,140 d含量最高[(25.69±0.42)%];多不饱和脂肪酸(PUFA)含量呈上升的变化趋势。肝胰腺中SFA含量在 3个生长时期内无显著性差异(P>0.05),MUFA含量呈先上升后下降的变化趋势,140 d含量最高[(37.44±0.59)%],而PUFA含量变化与MUFA正好相反。营养价值评估结果显示,180 d (可上市销售)的红螯螯虾肌肉内必需氨基酸指数(49.96%)高于联合国粮农组织/世界卫生组织(FAO/WHO)评分模式(31.50%)和全鸡蛋蛋白质模式(43.10%),是较为理想的优质食物蛋白源。由上可知,在不同生长时期,肌肉和肝胰腺中的氨基酸、脂肪酸的主要消耗不同,研究结果对了解不同生长时期红螯螯虾营养需求、开发红螯螯虾配合饲料提供了参考依据。     

细角螺肌肉氨基酸及脂肪酸组成分析

测定了细角螺(Hemifusus termatamus)腹足部肌肉的氨基酸含量与脂肪酸组成,并与方斑东风螺(Babylonia areolata)、管角螺(Hemifusus tuba)、棘角螺(Hemifusus kawamurai)和鲐鱼(Pneumatophorus japonicus)进行了比较。结果显示,细角螺肌肉中检出17种氨基酸,总含量为肌肉干重的81.03%,高于鲐鱼(79.86%)、方斑东风螺(66.45%)、管角螺(56.94%)和棘角螺(64.42%);肌肉中4种呈味氨基酸(天冬氨酸、谷氨酸、甘氨酸和丙氨酸)的含量为38.49%,占氨基酸总量的47.50%;8种必需氨基酸(EAA)总含量为38.49%,占氨基酸总量的46.94%。细角螺肌肉中共检出20种脂肪酸,其中饱和脂肪酸的含量为65.25%,不饱和脂肪酸的含量为34.75%,不饱和脂肪酸与饱和脂肪酸含量的比值为0.53,低于方斑东风螺(1.15)、管角螺(1.13)和棘角螺(0.69),高于鲐鱼(0.37)。结果表明,细角螺肌肉中必需氨基酸与不饱和脂肪酸含量较丰富,具有较高的营养价值,是一种较为理想的食物蛋白与脂肪来源。     

Protein Hydrolysate from Visceral Waste Proteins of Bolti Fish (Tilapia nilotica): Chemical and Nutritional Variations as Affected by Processing pHs and Time of Hydrolysis

The main objective of the current work was to evaluate the proximate chemical composition and nutritional quality of amino acids of protein hydrolysates from viscera of Tilapia nilotica fish. The results of amino acid composition showed that all hydrolysates contained sufficient and/or excessive amounts of both essential and nonessential amino acids, with appreciable values of essential amino acid/nonessential amino acid ratio (0.77 to 1.59) and essential amino acid/total amino acid ratio (43.35 to 61.35). All protein hydrolysates had a high content of the flavor enhancer amino acids. The lowest values of essential amino acids were found for phenylalanine and methionine with chemical scores ranging from 0.04 to 0.77 and 0.09 to 1.06, respectively, except for 18 h hydrolysates. The protein efficiency ratio had values greatly exceeding 2.0, which is considered a high quality. On the other hand, the levels of sugar and ash contents ranged from 2.69 to 3.32 g L^?1 and 0.48 to 2.1%, respectively, with 9.2 to 14% dry matter. Mineral composition showed that sufficient amounts of calcium, sodium, potassium, magnesium, and iron were present. The results suggest that the studied hydrolysates are appropriate for use in balanced human or animal diets.     

Nutritional Qualities of the Low-Value Bivalve Mollusks Paphia malabarica and Villorita cyprinoides at the Estuarine Waters of the Southwestern Coast of India

The bivalve mollusks Paphia malabarica and Villorita cyprinoides collected from the estuarine system located in the southwest coastal waters of India were evaluated for their nutritional composition. A balanced essential to nonessential amino acid ratio (> 1.0) with a greater quantity of sulfur-containing amino acids in these species demonstrated that they could provide well-balanced protein depositions. The n-3/n-6 polyunsaturated fatty acid ratio in P. malabarica was found to be greater than 2, and, therefore, can be considered as a healthy diet. The C₂₀–C₂₂ long-chain polyunsaturated n-3 fatty acids (for example, docosahexaenoic acid and eicosapentaenoic acid) accounted for more than 23% of the total fatty acid content in P. malabarica as compared to about 7% in V. cyprinoides. P. malabarica showed greater hypocholesterolemic/hypercholesterolemic ratio (1.7) and lesser atherogenicity (0.7), thrombogenicity (0.3) indices when contrasted with those in V. cyprinoides, thereby indicating the nutritional superiority of the former. A greater content of vitamin D₃ (> 150 IU), along with significant quantities of calcium and phosphorus (> 500 mg/100 g) in the clams, signified their importance in preventing osteoporosis. This study demonstrated the importance of bivalves, in particular, P. malabarica as a valued species for human consumption.     

Nutritional and Functional Properties of Two Dried Brown Seaweeds Sirophysalis trinodis and Polycladia myrica

Sirophysalis trinodis and Polycladia myrica, two brown seaweeds present on the southeast coast of Iran, were evaluated for their nutritional and functional properties after drying. Fourier transform-infrared spectroscopy (FTIR) analysis of crude polysaccharides revealed the characteristic absorption bands of phenol, O–H, C–H, C–O–S, C–O, C=O, C–H groups, and β-glycosidic linkages from cellulose, with the sulfate contents estimated as 4.89 ± 0.11% and 6.96 ± 0.05% of SO₄^?2. Results of nutritional profiles revealed all of the essential amino acids, especially methionine, isoleucine, leucine, lysine, threonine, valine, phenyl alanine, and arginine. In addition, important fatty acids such as linolenic acid, palmitic acid, and oleic acid were found in high amounts. The other nutritional components present in high amounts were proline and minerals such as calcium, magnesium, iron, manganese, copper, and zinc. The antibacterial activity was weak, but the result of antioxidant activities (hydroxyl and superoxide radicals scavenging and ferrous-ion chelating ability) of crude polysaccharides was considerable. In general, the findings of this study recommend that S. trinodis and P. myrica dried seaweeds have a potent nutritional value and might be used as a valuable source of nutrient supplements for humans and animals.     

Seasonal Changes in Quality and Fatty Acid Composition of Black Mussel (Mytilus galloprovincialis)

The study was designed to assess the seasonal variations in the quality and lipid profile of mussel meat (Mytilus galloprovincialis) harvested along the Bulgarian coast of the Black Sea. The trial period lasted from June to October, and the sampling was carried out in the area of Varna Bay. Technological quality of the mussels was determined by measuring the water holding capacity (WHC) and cooking and roasting losses. Proximate composition, total aerobic plate count, and fatty acid analysis were carried out. Technological parameters and nutritional quality of the mussel meat were strongly affected by the season. During the summer, the mussels had higher mass, meat content, and meat yield (p < 0.001) compared to the early autumn, which corresponds to the lowest protein content during this season. Lipid profile showed seasonal variations in both individual and total fatty acid amounts (p < 0.001). Saturated fatty acids (SFA) had the highest content in summer, while monounsaturated fatty acids (MUFA) decreased gradually until the autumn. The content of polyunsaturated fatty acids (PUFA) reached its peak in October, contributing to the most favorable values of the nutritional indices of lipids in the early autumn.     

Assessment of the Nutritive,Biochemical, Antioxidant and Antibacterial Potential of Eight Tropical Macro algae Along Kachchh Coast,India as Human Food Supplements

Eight tropical marine macro algae were investigated for in-vitro antioxidant, antibacterial, and biochemical properties. The moisture content [% DW (dry weight)] ranged from 7.21 to 14.72%; ash, 24.92 to 47.04%; lipids, 0.73 to 2.67%; protein, 4.56 to 12.59%; and carbohydrate, 30.1 to 48.51%. The % sum of polyunsaturated fatty acids (PUFAs) ranged from 21.71 to 78.22%, while omega-6/omega-3 (ω6/ω3) ratio was from 0 to 2.08, which remained within the prescribed World Health Organization (WHO) standards (<10). The % sum of essential amino acids (EAAs) ranged from 86.18 to 204.66, and Na/K ratio ranged from 0.37 to 2.85. The extracts exhibited significant (P < 0.05) values for total phenol (7.25–16.0 µg PGE mg^–1 DW) and total flavonoid (4.06–15.63 µg QE mg^–1 DW) at 200 µg/ml. Antibacterial activity was tested against the selected food spoilage and pathogenic bacteria. The principal component analysis (PCA) confirmed a positive correlation between total phenolic content, 1, 1-diphenyl-2-picryl-hydrazyl (DPPH) radical-scavenging activities, and ferric reducing antioxidant power (FRAP), which supports the integration of seaweeds as ingredients in functional foods.     

An Invasive Shrimp Species,Machrobrachium nipponense,in Anzali Wetland Demonstrated a Potential Source for Commercial Fishing

ABSTRACT

The proximate content, fatty acids composition, and nutritional quality index (NQI) of Macrobrachium nipponense at three habitats in the Anzali wetland in Iran were investigated as a potential source for human consumption. The highest amounts of protein, lipid, ash, and energy contents in muscle of M. nipponense were showed in autumn (non-reproductive season) (p < 0.05). The main monounsaturated fatty acids (MUFA) were oleic acid (C18:1 n9 C, C18:1 ω9 T) and palmitoleic acid (C16:1). Moreover, the main polyunsaturated fatty acids (PUFA) were docosahexaenoic acid (DHA, C22:6 n3), eicosapentaenoic acid (EPA, C20:5n3), arachidonic acid (ARA, C20:4 n6), linoleic acid (LA, C18:2 ω6), and α-linolenic acid (ALA, C18:3 n3). The predominant individual saturated fatty acid (SFA) was palmitic acid (0.07–13.4%), while oleic acid (14.7–26.3%), EPA (3.5–12.7%) and linoleic acid (0.04–14.9%) represented the most abundant individual MUFA and PUFA in M. nipponense. The highest mean value of EPA+DHA (14.0), n3/n6 (1.02), ΣMUFA/ΣSFA (1.05), ΣPUFA/ΣSFA (1.04), and EPA/DHA (3.8) ratios in M. nipponense was in autumn. The range of atherogenicity index (AI) and thrombogenicity index (TI) was much lower, from 0.42 to 0.6 and from 0.33 to 0.57, respectively, in terms of season. The results obtained in the present study show that M. nipponense is an excellent nutritional food source in the Anzali wetland.     

Preparation,Gel Electrophoresis Analysis,and Nutritional Evaluation of a Functional Krill Protein Concentrate with Low Fluoride Level from Antarctic krill (Euphausia superba)

A functional krill protein concentrate (FKPC) with low level of fluoride was prepared from frozen Antarctic krill (Euphausia superba) using isoelectric precipitation and phosphoric acid treatment. Variations in proteins and nutritional properties of the FKPC were analyzed. Gel electrophoresis analysis indicated that some variations in protein composition were introduced by autolysis and pH shift during the process of isoelectric precipitation and fluoride removal. The FKPC was composed of 81.01% ± 0.45% crude protein (dry basis) and 16.78% ± 0.26% total lipid (dry basis), exhibited excellent amino-acid composition in all the essential amino acids, exceeding the requirements of the FAO/WHO/UNU for food protein, and was rich in omega-3 polyunsaturated fatty acids, especially eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids present in phospholipids. The fluoride level of FKPC was 79.79 ± 2.10 μg/g (dry basis), which met the USFDA requirements. The surimi yield reached 43.74%, and the mean recovery rate of protein and fat was 52.68% and 41.44%, respectively. The nutritional value, safe level of fluoride, and high yield rate provide evidence that FKPC has a promising future in the food industry as a new aquatic protein and lipid resource.     

栅藻B38营养成分分析及蛋白质营养价值评价

对栅藻B38的营养成分进行了全面分析,结果表明,栅藻藻粉中油脂含量14%,总糖含量13.86%,粗纤维3.52%,灰分4.28%,蛋白质49.0%,为高蛋白质类微藻。栅藻B38中含有23种脂肪酸。栅藻B38中氨基酸总量为852.58 mg/g,必需氨基酸占总氨基酸的47.45%,必需氨基酸指数为85.42%。两种模式的氨基酸比值系数分较接近,均在65以上;待评价物质的氨基酸品质与模式蛋白的贴近度接近1(0.93和0.88)。栅藻B38中共检测出23种矿物质元素,其中钠、钾、钙、镁、铁、铝含量较为丰富。重金属的含量均低于国家食品卫生标准。栅藻B38中维生素B3(106.02 mg/100 g)和维生素E(540.77 mg/100 g)的量较高。综上,栅藻B38的营养较丰富,可以进一步开发利用。     

Nutritional quality of Metamysidopsis insularis Brattegard (Crustacea: Mysidacea)

In natural conditions the mysid Metamysidopsis insularis is commonly found in the littoral lagoon of Margarita Island (Venezuela). It is used as live food in the marine fish culture. However, its nutritional quality is not well documented. In the present study we analysed the nutritional value (total protein, carbohydrate and lipids profile) of M. insularis. The mysids were collected in La Restinga lagoon (Margarita Island, Venezuela). Levels of total proteins, lipids and carbohydrates were 700 ± 28.5, 160 ± 13.9 and 20 ± 0.90 g kg^?1 respectively. The lipids classes were 427 ± 2, 106 ± 98, 287 ± 113 and 179 ± 87 for phospholipids, triglycerides, cholesterol and cholesterol esters respectively. The fatty acids profile, determined by gas chromatography, showed important concentration of fatty acids for the metabolism of marine organism, such as 16:0, 18:0, 18:2n‐6, 18:3n‐3, 18:4‐3, 20:5n‐3 and 22:6n‐3; attaining levels of 27.49% in PUFA n‐3 and 2.92% in n‐6. The relation of eicosapentaenoic acid/docosahexaenoic acid was 2.1 ± 0.15. The results support the use of M. insularis as food for species of fish and crustaceans under culture conditions.     

Fatty Acid Profiles and Lipid Oxidation Status of Sun Dried,Deep Fried,and Smoked Sardine (Rastrineobola argentea) from Lake Victoria,Tanzania

Freshwater fishes contain long chain omega-3 and omega-6 polyunsaturated fatty acids (PUFAs) of highest nutritional value. PUFAs in fish are susceptible to oxidative damage during processing and subsequent storage. Sardines (Rastrineobola argentea) are an important fish species of Lake Victoria, constituting 72.3% of the total landings by weight on the Tanzanian side of the lake. Fatty acid profiles and lipid oxidation status of sun-dried, deep-fried, and smoked sardines were investigated. Lipid oxidation was assessed by peroxide value, thiobarbituric acid reactive substances (TBARS), and free fatty acids. Fatty acids were analyzed by gas chromatography with flame ionization detector. The three omega-3 PUFAs: docosahexaenoic acid (C22:6n-3), docosapentaenoic acid (C22:5n-3), and eicosapentaenoic acid (C20: 5n-3) contributed 57–60, 63, and 38% of PUFAs in sun-dried, smoked, and deep-fried sardines, respectively. Lipid oxidation reactions were more pronounced in sardines dried on sand and rocks, with TBARS values 97.87 and 84.18 µmolMDA/kg, respectively. The polyene index was significantly lower (p < 0.05) in deep-fried sardines, indicating lower retention of PUFAs in the product. Lake Victoria sardines are a rich source of omega-3 PUFAs. PUFAs in sun-dried sardines are prone to oxidative damage. Smoking resulted in relatively higher retention of omega-3 fatty acids in products.     

皮氏蛾螺肌肉营养成分分析与评价

采用生化手段对皮氏蛾螺肌肉中营养成分进行检测与分析。结果表明:皮氏蛾螺肌肉中水分含量为75.78%,蛋白质含量为15.70%,脂肪含量为0.50%,灰分含量为1.50%。皮氏嫂螺肌肉氨基酸总含量为58.21 g/100 g,共检测出17种氨基酸:半胱氨酸(Cys)含量最高,含量为11.35 g/100 g,其次是精氨酸(Arg)、天冬氨酸(Asp)和甘氨酸(Gly),组氨酸(His)含量最低,含量为0.39 g/100 g。共检测到6种呈味氨基酸,分别为天冬氨酸(Asp)、丝氨酸(Ser)、谷氮酸(Glu)、甘氨酸(Gly)、丙氨酸(Ala)及脯氨酸(Pro)。呈味氨基酸(DAA)总量为23.07 g/100 g。共检测出25种脂肪酸,其中包括9种饱和脂肪酸(SFA),16种不饱和脂肪酸(UFA)。在所有脂肪酸中,二十碳五烯酸EPA(C20:5i3)含量最高,达19.75%;而十五碳一烯酸(C15:1)含量最低,仅0.26%。     

2种乌贼肌肉的营养成分及品质评价

为了探究2种乌贼肌肉营养成分及品质差异,评价其营养价值,本研究对浙江舟山地区捕获量较大的日本无针乌贼(Sepiella japonica)和金乌贼(Sepia esculenta)的常规营养成分、质构特性、蒸煮损失率、甲醛含量、氨基酸和脂肪酸组成及矿物元素进行了分析。结果显示,日本无针乌贼肌肉的粗蛋白、粗脂肪含量与金乌贼相比无显著差异(P>0.05),水分含量显著低于金乌贼(P<0.05),粗灰分含量显著高于金乌贼(P<0.05)。金乌贼肌肉的硬度、弹性、胶粘性、咀嚼性和内聚性均显著高于日本无针乌贼(P<0.05)。2种乌贼肌肉的甲醛含量分别为0.56和1.18 mg/kg,均符合国家卫生标准。氨基酸测定结果显示,2种乌贼的肌肉中均检测出17种水解氨基酸,第一限制性氨基酸均为色氨酸;其中,必需氨基酸占总氨基酸的比例均高于31%,金乌贼与FAO/WHO推荐的理想蛋白模式更接近,其必需氨基酸指数(EAAI)高达82.99。脂肪酸测定结果显示,2种乌贼的肌肉中均检测出20种脂肪酸;其中,C20:5n-3 (EPA)和C22:6n-3 (DHA)的总含量均高于40%,且日本无针乌贼显著高于金乌贼(P<0.05)。2种乌贼肌肉富含人体所需的多种无机元素,常量元素中K和P含量最高,微量元素中Zn和I含量最高。研究表明,2种乌贼肌肉的营养成分及品质存在一定的差异,但均属于优质的低脂蛋白,具有较好的开发利用价值。本研究为开发利用东海头足类海洋资源提供了一定的依据和参考。     

Nutritional evaluation of fatty acids for the open thelycum shrimp, Litopenaeus vannamei: II. Effect of dietary n-3 and n-6 polyunsaturated and highly unsaturated fatty acids on juvenile shrimp growth, survival, and fatty acid composition

This study evaluated the nutritional value of dietary n‐3 and n‐6 polyunsaturated fatty acids (PUFA) such as linoleic (LOA) and linolenic (LNA) acids, and highly unsaturated fatty acids (HUFA) such as arachidonic (AA), eicosapentaenoic (EPA), and docosahexaenoic (DHA) acids for juvenile Litopenaeus vannamei, based on their effects on growth, survival, and fatty acid composition of hepatopancreas and muscle tissue. Diets contained 5% total lipid. A basal diet contained palmitic and stearic acids each at 2.5% of diet. Five diets contained 0.5% dry weight of LOA, LNA, AA, EPA, or DHA. An additional diet evaluated HUFA in combination by supplementing at 0.5% of diet, a mixture of n‐3 HUFA. All HUFA showed higher nutritional value than PUFA for shrimp and produced significantly (P < 0.05) higher final weight, weight gain, and total lipid in shrimp muscle. Fatty acid profiles of shrimp tissues reflected the composition of the dietary lipids. In general, saturated fatty acids were more abundant in the neutral factions, while PUFA and HUFA were more abundant in the polar fractions of tissues. Under these experimental conditions, HUFA had much greater nutritional value than PUFA for juvenile L. vannamei; moreover, dietary requirements for PUFA were not demonstrated.     

Chemical Characteristics of Different Tissues of Spectacled Caiman (Caiman crocodilus)

Proximate compositions of dorsal, ventral, leg, and tail cuts of farmed spectacled caiman (Caiman crocodilus) were determined. The water, protein, fat, and ash contents of muscle were 77–78%, 19–23%, 0.3–1.2%, and 1.0%, respectively. The dominant nucleotide-related compound in the tissues was inosine monophosphate (IMP) (68.6–84.9%). The predominant free amino acids (FAAs) in the muscle of spectacled caiman were taurine (Tau), glycine (Gly), alanine (Ala), and histidine (His), along with a dipeptide of anserine (Ans) (80–183 mg/100 g) and carnosine (Car) (35–103 mg/100 g) being detected in each sample. The major fatty acid composition included palmitic (16:0), oleic (18:1 cis-9), linoleic (18:2n-6), and stearic (C18:0) acids. The amount of docosahexaenoic acid (4.27–8.76%) was higher than that of eicosapentaenoic acid (0.99–2.24%). The ratio of polyunsaturated fatty acid/saturated fatty acid in spectacled caiman (0.83–1.19) was higher than that in other commonly consumed meat. Meat from the spectacled caiman can be characterized as a valuable food for human consumption in terms of these nutritional features.