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1.
BACKGROUND: Black scabbard fish ( Aphanopus carbo Lowe, 1839) is a deep‐water fish resource that is highly appreciated in southern European countries and can accumulate high levels of mercury in the muscle. Currently, European legislation establishes limits for the presence of toxic contaminants in raw seafood, despite these products are generally cooked before consumption. In addition, there is still a lack of information concerning the nutritional quality and contaminants available in cooked products. Therefore, the aim of this study was to assess the effect of sex, maturation stages and three common cooking practices (steaming, grilling and frying) on the toxic elements (Hg, As, Cd and Pb) and nutritional value (chemical, elemental and fatty acid composition) of black scabbard fish. RESULTS: Few variations occurred between sexes and maturation stages, particularly in fatty acid and elemental content. Concerning cooked black scabbard fish, the greatest differences occurred in fried and grilled samples, attaining higher Hg levels, whereas steamed fish composition was closer to raw black scabbard fish. CONCLUSION: Raw and cooked black scabbard fish can be considered as a very good source of essential nutrients such as n‐3 PUFA, proteins, macro and trace elements. Yet, when the fish is grilled, the Hg content may be above the limits set by EU. Considering the alterations occurred during the cooking processes, steaming seems the best procedure to cook this species. Copyright © 2011 Society of Chemical Industry  相似文献   

2.
Concentrations of mercury (Hg) in swordfish (Xiphias gladius) present a food safety problem for many countries. This study analyses total Hg (t-Hg) concentrations in 27 samples of swordfish marketed in Spain in 2005 and in their bioaccessible fractions (soluble concentration in gastrointestinal medium), obtained after applying an in vitro digestion method. Methylmercury (MeHg) was also determined in the bioaccessible fractions. t-Hg concentrations in the samples were 0.41–2.11 mg kg?1 wet weight, with a mean of 0.96 ± 0.47 mg kg?1 wet weight. A total of 37% of the samples exceeded the Hg limit set by Spanish legislation (1.0 mg kg?1 wet weight). Bioaccessible t-Hg concentrations were 0.17–1.72 mg kg?1 wet weight (0.63 ± 0.4 mg kg?1 wet weight), corresponding to 38–83% (64% ± 14%) of t-Hg. Bioaccessible MeHg concentrations, representing 94% of the bioaccessible t-Hg concentrations, were 0.16–1.53 mg kg?1 wet weight, with a mean of 0.49 ± 0.32 mg kg?1 wet weight. Children and adults who regularly consume this product in Spain have Hg and MeHg intakes that exceed the tolerable daily intake limits recommended by the Food and Agricultural Organization/World Health Organization (FAO/WHO) and US Environmental Protection Agency (USEPA). These results show the need for recommendations about swordfish consumption by population groups at risk in Spain.  相似文献   

3.
Rice can contain a relatively high amount of arsenic (As). We evaluated total and inorganic As concentrations in 39 samples of different types of rice sold in Spain. The analyses were performed in raw rice and in rice cooked by boiling to dryness in water spiked with As(V) (0.1-1 microg mL(-1)). In raw rice, inorganic As represented 27-93% of total As: total As = 0.188 +/- 0.078 microg g(-1) dry weight (dw); inorganic As = 0.114 +/- 0.046 microg g(-1) dw. After cooking, the rice retained between 45% and 107% of the As(V) added to the cooking water, and the inorganic As concentrations ranged between 0.428 microg g(-1) dw (0.1 microg mL(-1) in the cooking water) and 3.89 microg g(-1) dw (1.0 microg microL(-1) in the cooking water). For raw rice, the inorganic As intake of the Spanish population (16 g raw rice/day) remains below the tolerable daily intake (TDI) proposed by the WHO (2.1 microg inorganic As/day/kg body weight). In rice cooked with water contaminated with As(V), this cereal intake is sufficient to attain the TDI. The results reveal the need to consider the determination of inorganic As and the influence of cooking when evaluating the risks associated with the consumption of rice.  相似文献   

4.
Abstract: Rice can easily accumulate arsenic (As) into its grain and is known to be the highest As‐containing cereal. In addition, the As burden in rice may increase during its processing (such as when cooking using As‐polluted water). The health risk posed by the presence of As in cooked rice depends on its release from the matrix along the digestive system (bioaccessibility). Two types of white polished long‐grain rice, namely, nonparboiled and parboiled (total As: 202 and 190 μg As kg?1, respectively), were cooked in excess of water with different levels of As (0, 10, 47, 222, and 450 μg As L?1). The bioaccessibility of As from these cooked rice batches was evaluated with an in vitro dynamic digestion process. Rice cooked with water containing 0 and 10 μg As L?1 showed lower As concentrations than the raw (uncooked) rice. However, cooking water with relatively high As content (≥47 μg As L?1) significantly increased the As concentration in the cooked rice up to 8‐ and 9‐fold for the nonparboiled and parboiled rice, respectively. Parboiled rice, which is most widely consumed in South Asia, showed a higher percentage of As bioaccessibility (59% to 99%) than nonparboiled rice (36% to 69%) and most of the As bioaccessible in the cooked rice (80% to 99%) was released easily during the first 2 h of digestion. The estimation of the As intake through cooked rice based on the As bioaccessibility highlights that a few grams of cooked rice (less than 25 g dry weight per day) cooked with highly As contaminated water is equivalent to the amount of As from 2 L water containing the maximum permissible limit (10 μg As L?1). Practical Application: Studies on As bioaccessibility are needed for determining human As intake from rice for use in accurate risk assessments to establish updated legislation regarding maximum level of As in food. High As bioaccessibility from parboiled rice (consumed by the majority of the people in South Asia), and the findings of high As levels in discarded rice gruel (fed to livestock), has implications for human and animal health.  相似文献   

5.
Total mercury was analysed in 188 samples of predatory fish purchased at the retail level in Canada in 2005. The average concentrations (ng g(-1), range) were: sea bass 329 (38-1367), red snapper 148 (36-431), orange roughy 543 (279-974), fresh water trout 55 (20-430), grouper 360 (8-1060), black cod 284 (71-651), Arctic char 37 (28-54), king fish 440 (42-923), tilefish 601 (79-1164) and marlin 854 (125-2346). The Canadian standard for maximum total mercury allowed in the edible portions of fish sold at the retail level is 1000 ng g(-1) for shark, swordfish, marlin, orange roughy, escolar and both fresh and frozen tuna. The standard is 500 ng g(-1) for all other types of fish. In this study, despite the small number of samples of each species, the 1000 ng g(-1) maximum was exceeded in five samples of marlin (28%). The 500 ng g(-1) maximum was exceeded by six samples of sea bass (20%), four of tilefish (50%), five of grouper (24%), six of king fish (40%) and one of black cod (13%).  相似文献   

6.
The organic mercury content of five commercially valuable fish species (cod, flounder, turbot, perch and herring) was determined by use of an invitro digestion model in order to assess health risk of fish caught within the Polish Exclusive Economic Zone of the Baltic Sea. Concentrations of total mercury and organic mercury were measured in the muscle tissue of fish and in the products of two-stage gastrointestinal digestion, using atomic absorption spectroscopy (AMA 254). The highest concentrations of organic mercury were found in the muscles of predatory fish that dwell in near-bottom waters. Based on a bioaccessibility estimate obtained from the in vitro digestion model, it was found that only 26-62% of organic mercury, depending on the species of fish, was released into the intestinal lumen during the digestion of muscle. Therefore, to postulate the potential toxicity of fish, based on the organic mercury content of the muscle tissue ingested by consumers, is unfounded. The risk assessment should be carried out on the basis of another parameter - the bioaccessibility of organic mercury.  相似文献   

7.
Total mercury was measured in the edible portions of 244 selected fish and shellfish purchased in Canada at the retail level. By species, average mercury concentrations ranged from 0.011 μg g-1 for oysters to 1.82 μg g-1 for swordfish. The predatory fish contained the highest concentrations of mercury: swordfish (mean 1.82 μg g-1, range 0.40-3.85 μg g-1), marlin (1.43, 0.34-3.19 μg g-1), shark (1.26, 0.087-2.73 μg g-1), and canned, fresh and frozen tuna (0.35, 0.020-2.12 μg g-1). Levels of mercury in the fresh and frozen tuna contained a mean of 0.93 μg g-1 (range 0.077-2.12 μg g-1) and were substantially higher than in the canned tuna (0.15, 0.02-0.59 μg g-1). In the canned tuna, mercury concentrations varied with subspecies, with the highest average concentrations being found in Albacore tuna (mean 0.26 μg g-1, range 0.19-0.38 μg g-1) and the lowest (0.047, 0.025-0.069 μg g-1) in five samples for which the subspecies of tuna were not identified. Mean concentrations of mercury in swordfish and fresh and frozen tuna were up to three times higher than reported for the USA. Dietary intake estimations found that provided fresh and frozen tuna, marlin, swordfish or shark are consumed once a month or less, the dietary intakes of total mercury by women of child-bearing age, averaged over 1 month, would fall below the Joint FAO/WHO Expert Committee on Food Additives provisional tolerable weekly intake for total mercury. The current Canadian advisory to children and women of child-bearing age is to limit their consumption of fresh and frozen tuna, swordfish and shark to no more than one meal per month.  相似文献   

8.
In Chile, upwellings occur periodically along the coasts, resuspending metals from the seafloor and reintroducing them to the food web. Chilean blue mussels, Mytilus chilensis, accumulate these toxic compounds and show high concentrations of cadmium. An in vitro simulated digestion method has been applied to specimens of M. chilensis previously contaminated with 109Cd, to measure the bioaccessibility of cadmium for humans. The effects of the cooking process on the cadmium content of this species and on the resulting change in dietary bioaccessibility have also been evaluated. While cooking resulted in an increase in cadmium concentration in mussel flesh, cadmium remaining in the cooked flesh was also significantly less bioaccessible than cadmium occurring in the raw tissue. Estimations made in this study show that the intake of Cd from mussels by the Chilean population does not exceed the toxicological reference values established by the FAO/WHO; consequently, a health risk situation is not indicated.  相似文献   

9.
探究海带和紫菜中6种必需元素(Cu、Fe、Mn、Zn、Co和V)与5种有害元素(As、Cd、Pb、Al和Sr)的生物可给性及胃、肠消化过程中As、Cd等有害元素的形态转化,分析加工过程对样品中元素含量、形态及生物可给性的影响,结果表明:紫菜对除Sr外10种元素的富集能力均显著高于海带,经加工,海带和紫菜中6种人体必需微...  相似文献   

10.
The presence of selected toxic heavy metals, such as cadmium (Cd), lead (Pb) and mercury (Hg), was investigated in fish and seafood products, namely, blue mussel, carpet shell clam, European squid, veined squid, deep-water rose shrimp, red mullet, European seabass, gilthead seabream, Atlantic cod, European hake, Atlantic bluefin tuna and swordfish so as to assess their human exposure through diet. Metals were detected by quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS) and hydride generation atomic absorption spectrometry (Hg-AAS). Measurements of Cd, Pb and Hg were performed by means of analytical methods validated in compliance with UNI CEI EN ISO/IEC 17025 [2005. General requirements for the competence of testing and calibration laboratories. Milano (Italy): UNI Ente Nazionale Italiano di Unificazione]. The exposure assessment was undertaken matching the levels of Cd, Pb and total Hg with consumption data related to fish and seafood products selected for this purpose. In order to establish human health implications, the estimated weekly intakes (EWIs) for Cd, Pb and Hg were compared with the standard tolerable weekly intakes (TWI) for Cd and provisional tolerable weekly intakes (PTWIs) for Pb and Hg stipulated by the European Food Safety Authority (EFSA) and the Food and Agriculture Organization/World Health Organization (FAO/WHO) Joint Expert Committee on Food Additives (JECFA). The found metal concentrations were largely below the maximum levels (MLs) established at the European Union level with the exception of Cd. This metal exceeded the MLs in squid, red mullet, European hake and Atlantic cod. Squid and blue mussel showed the highest Pb concentrations which accounted for 60% and 10% of the MLs, respectively. Highest Hg levels were found in predatory fish. The concentrations of Hg in swordfish, Atlantic bluefin tuna and red mullet accounted for 50%, 30% and 30% of the MLs, respectively. The EWIs for Cd, Pb and Hg related to the consumption of fish and seafood products by the median of the Italian total population accounted for 20%, 1.5% and 10% of the standard TWI for Cd as well as PTWIs for Pb and Hg, respectively. Furthermore, the EWIs estimated using consumption data concerning Italian consumers did not exceed the standard TWI and PTWIs, except for Cd at 95th percentile.  相似文献   

11.
The aim of this study was to evaluate the bioaccessibility of polyphenols and antioxidant activity in cooked pulses and to study the effect of cooking on their total phenolic content (TPC) and antioxidant capacity. Cooked faba beans showed the highest TPC, followed by soybeans and lentils or peas. TPC ranged from 10.4 ± 0.2 to 52.9 ± 0.3 mg/100 g and was positively correlated with antioxidant activity. Cooking resulted in increased TPC and antioxidant activity of the methanolic extracts, caused by cell disruption and improved extraction of polyphenols. Although polyphenols were lost in the cooking water, boiled legumes had more polyphenols than those resulting cooking broths. In vitro gastrointestinal digestion resulted in increased TPC and antioxidant capacity of the extracts. Soybeans showed the highest amount of bioaccessible polyphenols. The release of phenolics from cooked legumes was mainly achieved during the intestinal phase. Literature data may underestimate the TPC and antioxidant capacity of pulses.  相似文献   

12.
The presence of tetrahydro-beta-carbolines and beta-carbolines was studied in raw, cooked and smoked fish and meat. 1,2,3,4-Tetrahydro-beta-carboline-3-carboxylic acid (THCA) usually was the major beta-carboline found, whereas 1-methyl-1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid (MTCA) appeared in smoked and 'well done' cooked samples. THCA was detected in raw fish (nd-2.52 micrograms/g), cooked fish (nd-6.43 micrograms/g), cooked meats (nd-0.036 microgram/g), smoked fish (0.19-0.67 microgram/g) and smoked meats (0.02-1.1 micrograms/g). Smoked and cooked samples contained higher amounts of THCA and MTCA than raw products. Deep cooking of fish and meat increased both THCA and MTCA, and this was accompanied by the formation of more beta-carbolines, norharman and harman. The tetrahydro-beta-carbolines THCA and MTCA were chemical precursors of the co-mutagens norharman and harman during cooking. These and previous results confirm that foods are an important source of beta-carbolines in humans.  相似文献   

13.
Total mercury concentrations were measured in fish and shellfish and their products imported into the UK and also in UK-produced farmed salmon and trout. Three hundred and thirty-six samples were collected using a two-stage sampling plan. The sample plan was weighted to reflect consumption, but with some bias towards fish that might accumulate higher levels of mercury, such as large predatory fish at the top of the food chain. The highest levels of total mercury were found in billfish (swordfish and marlin) and shark. Mercury concentrations in the five samples of fresh/frozen shark ranged from 1.006 to 2.200 mg kg -1 , all above the European Commission limit for the species, and concentrations in 20 samples of fresh/frozen billfish ranged from 0.153 to 2.706 mg kg -1 with 13 samples above the 1.0 mg kg -1 limit for the species. One sample of Antarctic ice fish was collected and had a mercury concentration of 0.664 mg kg -1 . The limit for this species was 0.5 mg kg -1 . One sample of fresh/frozen tuna out of the 20 collected had a mercury concentration above the limit of 1.0 mg kg -1 (1.5 mg kg -1 ), but all other fresh tuna samples were well within the regulatory limit (average 0.4 mg kg -1 ). Mercury concentrations in canned tuna were lower with concentrations on average half that measured in fresh/frozen tuna. Mercury concentrations in UK-farmed salmon and trout were relatively low. The maximum concentration found in 46 samples of fresh/frozen or smoked trout and salmon was 0.103 mg kg -1 .  相似文献   

14.
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.  相似文献   

15.
Total mercury (Hg), cadmium (Cd) and lead (Pb) levels were determined in the muscle of four commercialised exported fish species Thunnus albacares (yellowfin tuna), Xiphias gladius (swordfish), Makaira indica (black marlin) and Lutjanus sp (red snapper) collected from the Indian Ocean, Sri Lanka, during July 2009–March 2010 and measured by atomic absorption spectrophotometry. Results show that swordfish (n = 176) contained the highest total Hg (0.90 ± 0.51 mg/kg) and Cd (0.09 ± 0.13 mg/kg) levels, whereas yellowfin tuna (n = 140) contained the highest Pb levels (0.11 ± 0.16 mg/kg). The lowest total Hg (0.16 ± 0.11 mg/kg), Cd (0.01 ± 0.01 mg/kg) and Pb (0.04 ± 0.04 mg/kg) levels were found in red snapper (n = 28). Black marlin (n = 24) contained moderate levels of total Hg (0.49 ± 0.37), Cd (0.02 ± 0.02) and Pb (0.05 ± 0.05). Even though there are some concerns during certain months of the year, this study demonstrates the safety of main export fish varieties in terms of total Hg, Cd and Pb.  相似文献   

16.
The mercury (Hg) poisoning of Minamata Bay of Japan widely activated a global attention to Hg toxicity and its potential consequences to the aquatic ecosystem and human health. This has resulted to an increased need for a dynamic assembly, contextualization, and quantification of both the current state-of-the-art and approaches for understanding the cause-and-effect relationships of Hg exposure. Thus, the objective of this present review is to provide both hazardous toxic properties and toxicological update of Hg, focusing on how it ultimately affects the aquatic biota to potentially produce human health effects. Primarily, we discussed processes that relate to Hg exposure, including immunological aspects and risk assessment, vulnerability, toxicokinetics, and toxicodynamics, using edible fish, swordfish (Xiphias gladius), as a model. In addition, we summarized available information about Hg concentration limits set by different governmental agencies, as recognized by national and international standardization authorities.  相似文献   

17.
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.  相似文献   

18.
The docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) contents of Pacific saury (Cololabis saira), a fatty fish and staple of the Japanese diet, have been reported to decrease after cooking. This study compared the DHA and EPA contents remaining in saury after grilling, pan‐frying or deep‐frying to center temperatures of 75, 85, or 95 °C, and examined physical loss, lipid oxidation, and thermal degradation as mechanisms of DHA and EPA loss. Temperature changes inside the saury were monitored using thermocouples, while DHA and EPA contents, oxygen radical absorbance capacity, and measurements of lipid oxidation (that is, carbonyl value and thiobarbituric acid value) were determined chemically. Visualization of temperature distribution inside fish samples during cooking revealed large differences in heat transfer among cooking methods. True retention rates in grilled (DHA: 84 ± 15%; EPA: 87 ± 14%) and pan‐fried samples (DHA: 85 ± 16%; EPA: 77 ± 17%) were significantly higher than deep‐fried samples (DHA: 58 ± 17%; EPA: 51 ± 18%), but were not affected by final center temperatures despite differences in cooking times. Physical loss via cooking losses (grilling and pan‐frying) or migration into frying oil (deep‐frying) accounted for large quantities of DHA and EPA loss, while lipid oxidation and thermal degradation did not appear to be major mechanisms of loss. The antioxidant capacity of saury was not significantly affected by cooking treatments. The results of this study suggest that minimization of physical losses during cooking may increase DHA and EPA contents retained in cooked Pacific saury.  相似文献   

19.
Most information about drug residues is related to their concentrations in raw products. The objective of this study was to assess the effects of various microwave and boiling treatments on the stability of different concentrations of tylosin in chicken meatballs. The chicken meatball samples (75 g) were prepared and fortified by 3 concentrations of tylosin (100, 200 and 300 μg kg?1) and were cooked by boiling (100 °C for 10, 20, 30 min) and microwave procedure (power 450 W for 1, 1.5 and 2 min). The tylosin content was measured in raw and cooked samples through the use of high performance liquid chromatography. The microwave and the boiling process significantly reduced the tylosin. In both procedures, there were negative correlations between the length of cooking time and the reduction percentage of tylosin. In addition, tylosin reduction percentage in chicken meatball cooked by boiling depended on its concentration in uncooked samples. There was a relationship between tylosin reduction percentage and the increase in the internal temperature and weight loss during the cooking process. The results of this study indicate that tylosin residues in the food are decreased during the cooking process. Thus, given that a food product is cooked to be consumed, the surveillance of data obtained from tylosin measurement in the raw tissues samples could not be considered as consumers’ exposure to tylosin via dietary intake.  相似文献   

20.
为了研究蒸煮处理及紫苏水提物对脆肉鲩鱼片冻藏品质的影响,以紫苏水提物浸泡的生鱼片(生鱼片组)、紫苏水提物浸泡再进行蒸煮制备的熟鱼片(熟鱼片组)、蒸馏水浸泡的生鱼片(对照组)为研究对象,研究这3 组鱼片在冻藏过程中质构、持水性、盐溶性蛋白含量、Ca2+-ATPase活性、硫代巴比妥酸(thiobarbituric acid,TBA)值、挥发性盐基氮(total volatile base-nitrogen,TVB-N)含量和感官评分的变化。结果表明:熟鱼片及生鱼片组通过最大冰晶生成带的时间比对照组长;与对照组和生鱼片相比,熟鱼片在冻藏过程中一直维持较高的硬度、弹性、咀嚼性、TBA值和较低的持水力、盐溶性蛋白含量、TVB-N含量;与对照组相比,生鱼片组的质构特性、持水力、盐溶性蛋白含量和Ca2+-ATPase活力更高,而TBA值和TVB-N含量更低,冻藏300 d后,生鱼片TBA值是贮藏初始时的3.85 倍,TVB-N含量低于20 mg/100 g;感官评价结果进一步表明,3 组样品感官品质在冻藏过程中不断下降,其质地、口感以及汤汁浑浊度评分从高到低依次是熟鱼片、生鱼片和对照组。研究结果证明了紫苏水提物联合蒸煮处理更有利于冻藏过程中脆肉鲩鱼片品质的维持。  相似文献   

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