Differences in the ω3 Fatty Acid Contents in Pond-Reared and Wild Fish and Shellfish

The fatty acid composition of total lipids from edible portions of pond-reared prawn, catfish, and crayfish were compared with those of their wild counterparts. It was found that the lipids of the cultured animals had higher levels of ω6 fatty acids and lower ω3 fatty acid levels and ω3/ω6 ratios compared with their wild counterparts. The pelleted catfish diet was rich in ω6 fatty acids. It was concluded that the lipids of pond-reared fish and shellfish may not have the high levels of ω3 fatty acids found in wild seafood, and that the feasibility of increasing the ω3 fatty acid content by dietary manipulation, needs to be investigated.     

四种野生蔬菜营养成分分析

本文选取人们经常食用的四种野生蔬菜（车前草、积雪草、乌点规、芭蕉花）,分析了其中的粗蛋白、氨基酸、粗脂肪、维生素C等营养成分,并与小白菜、生菜和油菜三种常见栽培蔬菜进行比较,评价其营养价值。结果表明:四种野生蔬菜水分含量低于三种栽培蔬菜;粗蛋白和粗脂肪含量明显高于三种栽培蔬菜,其中,车前草、积雪草、芭蕉花三种蛋白含量均超过10%,芭蕉花中的粗脂肪含量最高;乌点规的维生素C含量最高达到36.29 mg/100 g鲜重,高于三种栽培蔬菜;总氨基酸含量顺序为:车前草>积雪草>芭蕉花>乌点规,车前草中含有丰富的必需氨基酸、支链氨基酸和鲜味氨基酸;芭蕉花中含有较高的赖氨酸。可见,四种野生蔬菜的营养丰富,有较高的食用价值,具有广阔的开发前景。     

Flesh quality of market-size farmed and wild British Columbia salmon

This study compared the flesh quality of farmed and wild sources of British Columbia (BC) salmon with respect to concentrations of polychlorinated biphenyl compounds, polychlorinated dibenzodioxins/dibenzofurans and their associated toxic equivalents, total mercury (THg), methylmercury (MeHg), and selected fatty acids of known importance for human health viz., omega-3 (n-3) highly unsaturated fatty acids (n-3 HUFAs) and (n-6) fatty acids. Skinned fillets from known sources of farmed Atlantic, coho, and chinook salmon (n = 110) and wild coho, chinook, chum, sockeye, and pink salmon (n = 91) were examined. Atlantic salmon contained higher PCB concentrations (means, 28-38 ng/g) than farmed coho or chinook salmon, and levels in these latter species were similar to those in wild counterparts (means, 2.8-13.7 ng/g). PCB levels in Atlantic salmon flesh were, nevertheless, 53-71-fold less than the level of concern for human consumption of fish, i.e., 2000 ng/g as established by Health Canada and the U.S. Food and Drug Administration (US-FDA). Similarly, THg and MeHg levels in all samples were well below the Health Canada guideline (0.5 microg/g) and the US-FDA action level (1.0 microg/g). On average, THg in farmed salmon (0.021 microg/g) was similar to or lower than wild salmon (0.013-0.077 microg/g). Atlantic salmon were a richer source (mean, 2.34 g/100 g fillet) of n-3 HUFAs than the other farmed and wild sources of salmon examined (means, 0.39-1.17 g/100 g). The present findings support the recommended weekly consumption guidelines for oily fish species (includes all BC salmon sources) for cardio-protective benefits as made by the American Heart Association and the UK Food Standards Agency.     

A comparison of selected quality features of the tissue and slaughter yield of wild and cultivated pikeperch<Emphasis Type="Italic"> Sander lucioperca</Emphasis> (L.)

The study focused on the comparison of carcass and fillet yields, fillet color, the content of basic components, and the fatty acid composition of tissue from cultivated and wild pikeperch. There was no variation in yield between carcasses and fillets. The brightness and redness of the color of the fillet surfaces of both types of fish were comparable, although the yellowness, chromaticity and shade of color differed. The tissue of cultivated fish had three times more fat (2.87%) than did that of wild fish; the difference was compensated for by water content. The protein and mineral component contents did not vary significantly. The total levels of saturated and monounsaturated acids in the tissue lipids in 1 g of fat varied. No differences were observed between the total amount of polyunsaturated fatty acids (PUFA), PUFAn-3, PUFAn-6, or in the n-3/n-6 proportion. One consequence of the higher fat content in cultivated pikeperch tissue was that the contents of eicosapentaenoic (EPA; 20:5n-3) and docosahexaenoic (DHA; 22:6n-3) acids per 100 g of fillet were significantly higher than in the tissue of wild pikeperch.     

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.     

云南6种食用菌中维生素B1和B2的含量调查

目的 调查分析云南省6种食用菌中维生素B1和B2的含量。方法 定点采集云南省6种常见新鲜食用菌, 按GB 5009.84-2016《食品安全国家标准 食品中维生素B1的测定》和GB 5009.85-2016《食品安全国家标准 食品中维生素B2的测定》, 用高效液相色谱法测定样品中的维生素B1和B2的含量。结果 6种常见新鲜食用菌中维生素B1的含量平均值最高的是虎掌菌0.0812 mg/100 g, 最低的是干巴菌为0.0298 mg/100 g; 维生素B2含量平均值最高的是干巴菌为0.587 mg/100 g, 平均值最低的是人工种植的羊肚菌为0.0510 mg/100 g。 结论 人工种植和野生的食用菌均含有一定量的维生素B1和B2, 具有一定的营养价值。     

Oil Content and Fatty Acids Composition in Brassica Species

Seeds of 20 accessions of six Brassica species including cultivated and five wild relatives were analyzed for oil and fatty acid composition. The results showed that oil content varied from 21 (B. nigra) to 46% (B. napus). Among wild species, B. rapa and B. oleracea had highest oil content (31 and 28%, respectively). The main fatty acids of oleic, linoleic, linolenic, erucic, palmitic, and stearic acids accounted for 89–94% of the total fatty acids in all species. Cultivated species of B. napus had highest oleic acid (61%) and lowest erucic acid (1%) content compared to other studied species. Brassica rapa and B. oleracea had the highest content of erucic acid (41 and 46%, respectively). The highest content of linolenic (20%) and linoleic (19%) acid was observed for B. juncea. The results showed that there was high genetic variation among the studied species for oil content and fatty acids composition. This indicates that seed oil of these species is possibly suitable for both human consumption and industrial purposes.     

陕北野生和不同栽培模式羊肚菌营养成分比较分析

目的:评估陕北野生和人工栽培羊肚菌的营养价值。方法:以陕北野生羊肚菌及驯化后以温棚、弓棚及林下3种模式栽培的羊肚菌子实体作为样品,依据国家标准通过常用方法对其营养成分进行检测分析。结果:在粗蛋白、粗脂肪、粗纤维和水分含量方面,所有人工栽培羊肚菌都比野生羊肚菌略高;并且人工栽培羊肚菌的氨基酸含量也比野生羊肚菌高,其中林下栽培羊肚菌的氨基酸配比最为合理;野生和人工栽培羊肚菌均含有丰富的不饱和脂肪酸,显著高于饱和脂肪酸含量,以油酸和亚油酸为主;野生和人工栽培羊肚菌均富含矿物质元素,而野生羊肚菌的矿物质元素含量更为丰富。结论:陕北地区人工栽培羊肚菌的营养价值不低于野生羊肚菌,但栽培模式不同会略有差异。     

Marine and farmed fish in the Polish market: Comparison of the nutritional value

The proximate composition and fatty acids profiles of the muscle tissues of nine fish species that are popular on the Polish market were examined. The nine studied fish species were: Baltic fish (cod, herring, salmon), fish farmed in Poland (carp, trout), oceanic fish imported from China (walleye pollock, sole), and farmed fish imported from Vietnam and China (sutchi catfish, tilapia). The lowest lipid content (below 0.1%) was noted in the muscle tissues of Baltic cod and walleye pollock caught in the Pacific. The muscle tissue of walleye pollock also had the lowest protein content (12.2 ± 2.0%). The highest lipid content was noted in the muscle tissues of Baltic salmon (13.1 ± 2.4%). The highest percentage content of eicosapentaenoic (C20:5 n − 3 – EPA) and docosahexaenoic (C22:6 n − 3 – DHA) acids (over 40%) was noted in the fat extracted from the oceanic fish and Baltic cod. However, due to the low fat content, the concentrations of EPA + DHA in these fish species and in imported farmed fish expressed in mg/100 g of muscle tissues are the lowest and range on average from 24.8 ± 5.7 mg/100 g (sutchi catfish) to 207.4 ± 125.4 mg/100 g (sole). This is why the consumption of these fish species has no significant meaning for coronary heart disease prevention. Consumers with symptoms of cardiovascular diseases should include the following fish species, which have high concentrations of EPA + DHA: Baltic salmon (3807.2 ± 666.3 mg/100 g); Polish farmed trout (1804.0 ± 279.2 mg/100 g); and Baltic herring (940.9 ± 306.6 mg/100 g) in their diets. However, the consumption of Baltic salmon must be limited on account of the levels of persistent organic pollutants found in it.     

小龙虾即食休闲食品的研制及品质分析

为填补小龙虾即食休闲产品的空白,该研究以小龙虾尾为原料,开发了一款即食小龙虾休闲食品。以感官评分为指标进行单因素和正交试验,优化了食盐、花椒和辣椒、鸡精和味精、煮制时间等因素对小龙虾休闲食品的影响,并对产品的质构、营养、风味等品质进行分析。结果表明,最佳的工艺配方为食盐2.5%,辣椒和花椒13.3%和2.98%,鸡精和味精添加量均为0.66%,煮制时间4 min,感官评分为76.66分。小龙虾虾尾硬度值为119.83 g,弹性值3.88,内聚性0.92,咀嚼性424.99;小龙虾产品中含水分55.85%、灰分4.07%、脂肪14.91%、粗蛋白18.79%、总糖3.87%;总氨基酸含量155.93 mg/g,其中必需氨基酸约占20%,其评分均大于1;总脂肪酸中不饱和脂肪酸约占83%;游离氨基酸含量为2.53 mg/g,其中呈鲜、甜味的氨基酸约占80%;核苷酸总量为71.28 mg/100 g,其中肌苷酸含量最多58.13 mg/100 g;鲜味强度为0.29 g MSG/100 g。小龙虾即食休闲食品含有丰富的营养与风味成分,且有弹性好、硬度适宜、耐咀嚼的特点。     

Investigation of selected persistent organic pollutants in farmed Atlantic salmon (Salmo salar), salmon aquaculture feed,and fish oil components of the feed

There is extensive literature documenting the bioaccumulation of persistent organic pollutants in the marine environment, but relatively little data are available on contamination pathways in aquaculture systems such as that for farmed salmon. In recent years,the salmon industry has grown significantly in Europe. This study reports on the determination of a wide range of polychlorinated biphenyls (PCBs), organochlorine pesticides, and polybrominated diphenyl ethers (PBDEs) in farmed and wild European Atlantic salmon fish, aquaculture feeds, and fish oils used to supplement the feeds. The study confirms previous reports of relatively high concentrations of PCBs and indicates moderate concentrations of organochlorine pesticides and PBDEs in farmed Scottish and European salmon. Concentrations of the selected persistent organic pollutants varied among the samples: PCBs (salmon, 145-460 ng/g lipid; salmon feeds, 76-1153 ng/g lipid; fish oils, 9-253 ng/g lipid), S DDTs (salmon, 5-250 ng/g lipid; salmon feeds, 34-52 ng/g lipid; fish oils, 11-218 ng/g lipid), and PBDEs (salmon, 1-85 ng/g lipid: salmon feeds, 8-24 ng/g lipid; fish oils, ND-13 ng/g lipid). Comparison of the samples for all groups of contaminants, except for HCHs, showed an increase in concentration in the order fish oil < feed < salmon. Homologue profiles were similar, with an increase in contribution of hepta- and octa-PCBs in the fish, and profiles of DDTs were similar in all three types of samples. With a constant contribution to the total PCB content, the ICES 7 PCBs appear to be reliable predictors of the PCB contamination profile through all the samples. For PBDEs, BDE 47 dominated the profiles, with no significant difference in the PBDE profiles for the three matrixes. Samples with higher PCB contents generally showed higher levels of the pesticide residues, but this was not the case with the PBDEs, indicating the existence of different pollution sources.     

人工栽培和野生羊肚菌游离氨基酸主成分分析及综合评价

采用氨基酸自动分析仪对云南、四川、吉林、甘肃的人工栽培和野生羊肚菌游离氨基酸(free aminoacids,FAAs)的组成及含量进行测定,通过滋味活性值(taste active value,TAV)比较其呈味特性,主成分分析法及聚类分析法进行综合评价.结果表明:野生羊肚菌中FAAs含量丰富,含18种氨基酸,总含量...     

不同酒曲生产小米酒的研究

采用6种不同酒曲生产小米酒,考察不同酒曲对其发酵酒的非糖固形物、酒精度、pH、总酸及氨基酸态氮含量的影响,并对其进行全营养成分分析。结果表明,最佳酒曲为QDYF-1,其发酵的小米酒总糖含量为0.42 g/L、非糖固形物含量为32 g/L、酒精度为11.2%vol、pH值为3.7、氨基酸态氮含量为3.41 g/L,碳水化合物含量为12.3 g/100 g,维生素B1含量0.088 mg/100 g,维生素B2含量为0.05 mg/100 g,氨基酸含量为0.365 g/100 g;其中,9种人体必需氨基酸含量为0.088 g/100 g。该产品色泽诱人、酸甜可口、带有米香味、营养丰富,具有非常好的保健功能。该研究可为小米酒的产业化生产提供重要依据。     

The effect of cooking methods on mineral and vitamin contents of African catfish

Proximate composition, mineral and vitamin contents (A, E, B₁, B₂, niacin and B₆) were investigated in cooked African catfish. Different cooking treatments were used (baking, grilling, microwaving and frying). The protein and ash contents increased in all cooked fish. The fat content increased only in fried fillets. The moisture content of cooked fish decreased. Mineral levels were affected by cooking methods, except for Cu Although the vitamin A content significantly increased in grilled and fried fish, vitamin E increased in all cooked fish. Vitamin B₁ content of cooked fish significantly decreased. Vitamin B₂ and niacin contents of grilled fish increased significantly. B₆ content of cooked fish significantly decreased but this did not occur for the grilled fish. High levels of vitamin and mineral contents were found in grilled catfish.     

Salmon by-product storage and oil extraction

Oils extracted from wild salmon by-products are excellent sources of long chain omega-3 polyunsaturated fatty acids including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). However, quality loss is expected if time delays are encountered before oil extraction. The free fatty acid levels (FFA), fatty acid profile and total fat soluble antioxidant activity in extracted oil from aging pink salmon heads and viscera stored at two temperatures (6 and 15 °C) for four days were determined. The FFA values in raw salmon heads and viscera increased with storage time and temperature. A significant difference (p < 0.05) from the starting material was noted at day 1 at both temperatures for FFA. Fatty acid composition data indicated no changes in the levels of long-chain omega-3 fatty acids with the respective temperature. The concentration of long-chain omega-3 fatty acids EPA ranged from 9.3 to 11.3 g/100 g of crude oil and DHA ranged from 12.3 to 13.1 g/100 g of crude oil. The antioxidant activity of the pink salmon oils at day 0 was 0.89 ± 0.15 μmole Trolox equivalent/g of crude oil. Significant decreases (p < 0.05) from the starting material were noted on day 2 for 15 °C samples and day 3 for 6 °C samples. After four days of storage antioxidant levels (Trolox equivalent/g of crude oil) were approximately 25% of initial values. Oil extracted from raw salmon heads and viscera remained a good source of long chain omega-3 fatty acids even after 4 days of raw material storage at 15 °C; however, fat soluble antioxidant activity was reduced and free fatty acid levels increased with increased raw material storage temperature and time.     

Composition of the seeds of some Amaranthus species

The seeds of the five commonly consumed Amaranthus species have been analysed for their chemical composition and starch characteristics. A notably high fat, protein and ash content in the seeds of a sample of A. teunifolious as compared with other species has been demonstrated. All the samples analysed had a high oxalate and phytic acid content. The size of the starch granules from all the samples was in the range 08.2.3μm and the circular shape of granules from all the species was strikingly similar. Amaranthus polygamous and A. gracilis had low amylose starches (111.7 and 97.1 g kg^?1, respectively), and A. spinosus and A. teunifolious had appreciable proportions of amylose (166.7 and 245.0 g kg^?1, respectively).     

On the specificity of tuna-directed primers in PCR-SSCP analysis of fish and meat

Single strand conformation polymorphism (SSCP) of an amplicon (148 bp) obtained by polymerase chain reaction (PCR) of the mitochondrial cytochrom b gene used to identify tuna species was studied with other fish and animal species. Single-stranded DNA (ssDNA) patterns of two to four strong bands were obtained with blue ling, carp, haddock, mackerel, mackerel shark, saithe, catfish, Alaska pollack, and skipjack which, however, differed from those obtained with tuna samples. Other fish species resulted in weak (cod, spined dogfish) or no ssDNA bands (Atlantic salmon, halibut, herring, pike-perch, plaice, redfish, sprat, trout). Samples from animals other than fish resulted in strong ssDNA bands differing from those of tuna and from each other (crayfish; cattle, European rabbit, fallow deer, hare, horse, red deer, roe deer; goose, turkey), in bands differing from tuna but not from each other (domestic goat/sheep, domestic pig/wild boar), or in weak bands (octopus, shrimp; chicken, duck). Increasing the stringency of PCR caused a more pronounced difference between strong and weak ssDNA bands. Inter-laboratory reproducibility of the method was good.     

Chemical compositions and characterisation of skin gelatin from farmed giant catfish (Pangasianodon gigas)

Gelatin was extracted from the skin of farmed giant catfish (Pangasianodon gigas) with a yield of 20.1 g/100 g skin sample on the basis of wet weight. The chemical composition and properties of gelatin were characterised. The gelatin had high protein (89.1 g/100 g) but low fat (0.75 g/100 g) content and contained a high number of imino acids (proline and hydroxyproline) (211 residues per 1000 residues). Giant catfish skin gelatin had a slightly different amino acid composition than calf skin gelatin. The bloom strength of the gelatin gel from giant catfish skin gelatin (153 g) was greater than that of calf skin gelatin (135 g) (P < 0.05). Viscosity, foam capacity and foam stability of gelatin from giant catfish skins were in general greater than those of the gelatin from calf skin tested. SDS-PAGE of giant catfish skin gelatin showed a high band intensity for the major protein components, especially, α-, β- and γ-components and was similar to that of standard calf skin collagen type I.     

Concentration of Selected Vitamins in Infant Milks Available in Spain

ABSTRACT: Vitamins A, E, and those of the B complex were determined in 59 standard and 11 specialized infant milks from the Spanish market. Water-soluble vitamin levels were lower than those declared by manufacturers in 50% of the standard infant milk products. Vitamin A ranged from 58.8 μg/100mL to 170.9 μ/100mL and vitamin E from 0.8 mg/100mL to 3.3 mg/100ml. Most of the samples had a higher vitamin A content than that stated by the manufacturer, and 13% and 42% of them exceeded the Spanish legislation and the ESPGAN recommendation levels respectively. Vitamin E levels were between 2 and 10 times higher than the minimum established by these organizations and in general were over the declared level.     

Microbial quality of raw aquacultured fish fillets procured from Internet and local retail markets

The microbial quality of raw fillets of aquacultured catfish, salmon, tilapia, and trout was evaluated. A total of 272 fillets from nine local and nine Internet retail markets were tested. Mean values were 5.7 log CFU/g for total aerobic mesophiles, 6.3 log CFU/g for psychrotrophs, and 1.9 log most probable number (MPN) per gram for coliforms. Differences in these microbial levels between the two kinds of markets and among the four types of fish were not significant (P > 0.05), except that Internet trout fillets had about 0.8-log higher aerobic mesophiles than did trout fillets purchased locally. Although Escherichia coli was detected in 1.4, 1.5, and 5.9% of trout, salmon, and tilapia, respectively, no sample had > or = 1.0 log MPN/g. However, E. coli was found in 13.2% of catfish, with an average of 1.7 log MPN/g. About 27% of all fillets had Listeria spp., and a positive correlation between the prevalence of Listeria spp. and Listeria monocytogenes was observed. Internet fillets had a higher prevalence of both Listeria spp. and L. monocytogenes than did those fillets purchased locally. L. monocytogenes was present in 23.5% of catfish but in only 5.7, 10.3, and 10.6% of trout, tilapia, and salmon, respectively. Salmonella and E. coli O157 were not found in any sample. A follow-up investigation using catfish operation as a model revealed that gut waste exposed during evisceration is a potential source of coliforms and Listeria spp.