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1.
Total (Ast), inorganic arsenic (Asi = As(III) + As(V)) and dimethylarsonic acid (DMA) were determined in 37 commercial rice samples collected in France. Ast was measured by inductively coupled plasma-mass spectrometry (ICP-MS) whereas anion-exchange chromatography – ICP-MS was used for Asi and DMA determination. Ast in raw rice varied from 0.041 to 0.535 mg kg−1 whereas Asi varied from 0.025 mg kg−1 (polished Basmati rice) up to 0.471 mg kg−1 (organic rice duo). The daily intake and associated health risk for different population groups as a function of age and gender was also assessed. The intake varied between 0.002 and 0.184 μg kg−1 body weight for Ast and 0.002 and 0.153 μg kg−1 body weight for Asi, which do not pose a chronic toxicity risk. Organic wholegrain rice may entail a risk for children in the case of sole consumption at the expense of polished rice. The impact of rice cooking/boiling in terms of the overall toxicological risk related to As species was also investigated. Pre-rinsing and boiling the raw rice by using an excess of water is the most efficient mode to obtain a significant Asi removal and further reduction of the toxicological risk for children, particularly for white rice varieties.  相似文献   

2.
Different honey types were collected in Croatia during 2010 and 2011: 7 multifloral orchard honeys, 7 multifloral meadow honeys, 19 black locust, 9 chestnut, 11 lime and 6 sage honeys. Elements were measured using graphite (As, Cu, Cd, Pb, Se) and flame atomic absorption spectrometer (Ca, Fe, K, Mg, Na, Zn) and by mercury analyser (Hg). Significant differences in Ca, Fe, K, Mg, Zn, As and Hg levels were observed between honey types. In chestnut honey were determined (K, Ca, Mg: mg kg−1; Hg, Ad, Cd: μg kg−1): the highest concentrations of K 2824.4, Ca 486.7, Mg 59.1 and Hg 2.52; the lowest of As 24.1 and Cd 2.52. Lime honey has been shown the highest content of Cu (20.6 mg kg−1), Zn (6.78 mg kg−1), Cd (2.14 μg kg−1) and Pb (810.3 μg kg−1). The lowest levels of following elements were determined in black locust honey (Fe, K, Mg: mg kg−1; Hg: μg kg−1): Fe 2.77, K 304.7, Mg 8.02 and Hg 0.82. Sage honey had the lowest Ca and Na content (173.9 and 31.8 mg kg−1). Among the multifloral honeys, the following was determined (Fe, Na, Cu: mg kg−1; As, Pb: μg kg−1): orchard honey – highest of Fe 5.17 and As 276.1, lowest Pb 301; meadow honey – highest Na 36.1, lowest Cu 4.38. The average Ca, Cu and Pb levels found in multifloral honey types were much higher than those reported in other European countries. Calcium levels in lime, chestnut and black locust were higher than those from other countries.  相似文献   

3.
Matched muscle, liver and kidney samples from 152 sheep in different states of Australia were analysed for trace elements. Mean levels found in muscle, livers and kidneys were 0.010, 0.010 and 0.011 mg kg−1 (fresh weight) for arsenic; 0.0035, 0.280 and 0.853 mg kg−1 for cadmium; 0.006, 0.060 and 0.044 mg kg−1 for cobalt; 0.74, 66.0 and 2.72 mg kg−1 for copper; 0.007, 0.040 and 0.057 mg kg−1 for lead; 0.0025, 0.0034 and 0.0061 mg kg−1 for mercury; 0.014, 1.05 and 0.44 mg kg−1 for molybdenum; 0.09, 0.31 and 0.95 mg kg−1 for selenium; and 40.4, 37.2 and 20.8 mg kg−1 for zinc. The lead, mercury and arsenic concentrations in meat and organs may be regarded as low, but the concentrations of cadmium in kidney and livers are sometimes relatively high. Apart from cadmium, lead and selenium, tissue trace element concentrations were not related to the age of the investigated animals. Differences in essential and non-essential trace element accumulation in sheep reared in different regions (states and territories) of Australia were also evaluated. Cadmium, lead and selenium were the only elements that appeared to show significant regional differences. Overall the results show that concentrations of the elements considered are within current acceptable ranges.  相似文献   

4.
The relevance of agronomic practices on the nutritional quality greenhouse-grown tomatoes has been recognized. We investigated the influence of (1) cultivar: two local (Pera-Girona and Montserrat) and one commercial (Caramba) varieties; (2) nitrogen dose in nutrient solution (low vs. standard N dose); (3) treatment for plant disease control (sulfur vs. Milsana®) and (4) ripeness (orange vs. full-red color) on levels of carotenoids, phenolic compounds, ascorbic acid and minerals of fruits. Carotenoids and ascorbate were mainly influenced by variety and ripening stage, while N dose slightly affected minerals in fruits; treatments against plant diseases exerted only negligible effects on measured compounds. Local tomato varieties appear more promising as food source of carotenoids, mainly lycopene, and of hydroxycinnamates, such as 5-caffeoylquinic acid and caffeoylquinic derivatives, than commercial variety (total carotenoids: 67.43 mg kg−1 fw vs. 56.34 mg kg−1 fw of Pera-Girona vs. Caramba and total hydroxycinnamates: 90.87 mg kg−1 fw vs. 37.90 mg kg−1 fw of Montserrat vs. Caramba, at full-red color). Tomato variety and harvest maturity of fruit were the main factors affecting nutritional value of tomatoes, while Milsana® treatment did not result in evident nutritional benefits. However, the use of this elicitor might be appropriate considering the increasing environmentally friendly attitudes of consumers.  相似文献   

5.
Calcium (Ca), magnesium (Mg), sodium (Na) and potassium (K) contents in 1319 foodstuffs habitually consumed by the French population were determined for the second French Total Diet Study (TDS), using micro-sampling flame atomic absorption spectrometry after microwave-assisted digestion. Concentration and distribution of these minerals in food samples were reported and compared with results from the previous French TDS. For Ca, the results indicate that the food presenting the highest levels are dairy products (1597 mg kg?1), tofu (802 mg kg?1) and some fish and cereal products; for Mg, tofu (1340 mg kg?1), “Sweeteners, honey and confectionery” (672 mg kg?1) especially dark chocolate (2225 mg kg?1) and certain grains such as nuts and oilseeds (1069 mg kg?1) and some cereal products; for Na, processed meats such as delicatessen (12,422 mg kg?1), “Salts, spices, soup and sauces” (21,028 mg kg?1), some cheeses and cereal products; and for K, “Cereal and cereal products” (4378 mg kg?1), “Meats and offal” (3993 mg kg?1), “Nuts and oilseeds” (7355 mg kg?1) and “Sweeteners, honey and confectionery” (3445 mg kg?1) (especially chocolate).  相似文献   

6.
A survey was conducted on the presence of hydroxymethylfurfural (HMF) and furfural in bread and bakery products; for this purpose a reliable extraction procedure followed by high performance liquid chromatography (HPLC) was applied. The performance of the method was evaluated in terms of linearity (r always > 0.99); detection limits (0.001 mg L−1 for furfural and 0.006 mg L−1 for HMF); recovery percentages (98.5–100.5% for HMF and 94.9–98.9% for furfural); intraday precision (<4.65%) and interday precision (<7.51%). Two batches of a wide variety of products commercially available were analysed (a total of 88 samples). HMF and furfural levels presented high variability between products and batches of the same product. Cake/pastry samples showed the lowest HMF content (3.0 mg kg−1 fw) while biscuits showed the highest content (7.8 mg kg−1 fw) (p < 0.05). Regarding furfural, bread samples presented the highest furfural content (5.3 mg kg−1 fw) (p < 0.05), cake/pastry and biscuits showed the lowest content (1.9 and 3.0 mg kg−1 fw, respectively). Chocolate containing samples presented higher amounts of furfural (>20 mg kg−1). These results indicate that special attention should be given to furfural content of bread (due to its daily high consumption) and re-evaluation of dietary exposure.  相似文献   

7.
The free amino acid composition and biogenic amine content were analysed in pasteurised goat milk cheeses produced in different regions in Spain. These goat cheeses are made with pasteurised milk to which a mesophilic starter culture is added; they are enzymatically coagulated, uncooked, pressed cheeses. They have a firm texture with a slight but typical goat milk aroma and flavour. The total free amino acids varied markedly among the samples, ranging from 1400 to 28,000 mg kg−1 DM (dry matter). Of the 20 amino acids analysed, the most abundant were leucine, proline, valine, glutamic acid, lysine, glutamine, ornithine and γ-aminobutyric acid, which accounted for over 60% of the total free amino acids. The goat milk cheeses presented low concentrations of biogenic amines, the most abundant being tyramine and/or histamine, with values ranging from 4.2 to 50.7 and from 10.2 to 60.5 mg kg−1 DM, respectively. Total biogenic amine content ranged between 26.4 mg kg−1 DM and 175.1 mg kg−1 DM, and was always below the level that is considered dangerous for humans. Therefore, taking into consideration the concentrations of BAs, these goat milk cheeses, produced under good hygienic conditions, can be considered safe for consumers.  相似文献   

8.
A flow-through system based on the integration of solid-phase spectroscopic detection implemented with photochemically induced fluorescence (PIF) is proposed for the determination of clothianidin (a non-fluorescent neonicotinoid insecticide) through a multicommutated method. The pesticide is injected into the carrier stream (0.015 mol L−1C2H4O2/NaC2H3O2, pH = 5.0) and flows towards a homemade photoreactor, which consists of a PTFE tubing loosely coiled around a low-pressure mercury lamp (15W). After the photochemical reaction of clothianidin, the generated fluorescent photoproduct is transported to a flow cell packed with Sephadex-SP C-25 where it is retained and monitored (λex = 357 nm/λem = 418 nm). The method presents a detection limit of 1.5 ng mL−1, a sample throughput of 23 h−1 and inter-day relative standard deviation lower than 3%. The described system has been satisfactorily applied to the determination of clothianidin in samples of drinking water, rice and honey. Taking into account that the maximum residue limit specified in the Codex Alimentarius Commission for rice grains is 0.5 mg kg−1, recovery experiments have been carried out for clothianidin concentrations in the 0.3-10.0 mg kg−1 range.  相似文献   

9.
The paper presents the application of liquid chromatography coupled with evaporative light scattering detector (LC-ELSD) for the determination of biogenic amines in different cheese samples, as their presence and relative amounts give useful information about freshness, level of ripening and quality of storage. Forty samples from different types of milk – hard-ripened, ripened and unripened – were considered. Results showed that the amine contents varied in relation to the manufacturing process, the highest concentration being in hard-ripened cheeses followed by ripened and then unripened. In hard-ripened cheeses amines were β-phenylethylamine (PHE) (69.8–136.6 mg kg?1), tyramine (TYR) (19.7–147.1 mg kg?1), spermidine (SPD) (nd–73.1 mg kg?1), cadaverine (CAD) (nd–64.7 mg kg?1), histamine (HIS) (17.6–48.2 mg kg?1), spermine (SPM) (nd–47.4 mg kg?1), putrescine (PUT) (nd–44.1 mg kg?1) and agmatine (AGM) (nd–4.2 mg kg?1); while in ripened cheese TYR (nd–116.7 mg kg?1), PUT (nd–82.9 mg kg?1), HIS (nd–57.7 mg kg?1), PHE (nd–51.1 mg kg?1), SPD (nd–31.5 mg kg?1), CAD (nd–30.7 mg kg?1), SPM (nd–26.9 mg kg?1) and AGM (nd–4.8 mg kg?1). On the basis of literature limits, in this study only hard ripened cheeses could represent a possible risk for consumers as they exceeded a proposed limit for PHE and total biogenic amines amount.  相似文献   

10.
The aim of the present study is the identification of plant sterols and the development of an analytical method that allows for the quantification of such family of compounds in oenological matrices. The application of liquid chromatography-atmospheric pressure chemical ionization ion-trap mass spectrometry (LC-APCI-ITMS) to sterol characterization is a useful tool and was selected to perform this research. Sterol separation was achieved using a C8 column with a mobile phase consisting of water and acetonitrile under gradient conditions and column temperature of 35 °C, which leads to analyte elution in less than 25 min. Retention times, precursor ions and MRM transitions of analytes allowed for the identification and sensitive quantitative determination of phytosterols in oenological matrices at trace levels. The method showed a dynamic linear range over the concentration ranges from 0.02 to 320 mg kg−1 for the different parts of grapes and from 8 to 100 ng mL−1 in case of wine. The most abundant phytosterol in all samples was β-sitosterol. The seeds are the richest source of phytosterols having a great amount of β-sitosterol, 314 mg kg−1 fresh berry mass, followed by stigmasterol, fucosterol and campesterol at much lower concentrations (ranging from 3 to 10 mg kg−1).  相似文献   

11.
A total of 28 minerals and trace elements from 1319 food samples typically consumed by the French population were determined during the second French Total Diet Study (TDS). Among the main trace elements analysed by inductively coupled plasma-mass spectrometry (ICP-MS) after microwave-assisted digestion, strontium (Sr), silver (Ag), tin (Sn), barium (Ba), iron (Fe), tellurium (Te), gallium (Ga), germanium (Ge) and vanadium (V) were retained for this work and their occurrence data reported here. The contents were compared using data from worldwide total diet studies. Data for tin in canned food and beverages were compared with European guidelines. The food groups with the highest levels were “Sweeteners, honey and confectionery” with dark chocolate (for Sr, Ag, Sn, Te, Ba, Fe Ga, Ge and V), “Fish and fish products” and particularly “Shellfish” (for Sr (14.3 mg kg?1), Ag (5.18 mg kg?1), Ga (0.002 mg kg?1), Ge (0.004 mg kg?1), Te (0.003 mg kg?1) and V (0.234 mg kg?1)), “Tofu” (for Sr (2.71 mg kg?1), Fe (29.0 mg kg?1) and Ba (0.824 mg kg?1)), “Ice cream” (Ba (0.621 mg kg?1), Fe (45.5 mg kg?1), Ag (0.193 mg kg?1)) and “Fat and oil” (for Te, Ga and Ge). Moreover, the highest concentrations of Sn were found in “Fruits and vegetables” (0.522 mg kg?1).  相似文献   

12.
As the brown meat of crabs accumulates cadmium (Cd) to elevated concentrations, the European Commission has recommended consumer advice on the consumption of such seafood products. To supplement available data, 397 samples (including whole crabs and products containing brown crab meat) were collected from UK retailers. Cd concentrations ranged from 0.01 to 26 mg kg −1 wet weight (ww) and mean and median concentrations of 3.4 and 2.8 mg kg−1 were found, respectively. Although there is no regulatory limit for Cd in brown crab meat, mean concentrations were above the permitted maximum of 0.5 mg kg−1 that applies to the white meat component derived from claws and legs. These data will support the UK Food Standards Agency’s risk assessment and management measures regarding the consumption of brown crab meat by UK consumers.  相似文献   

13.
Several ancient apple varieties and a wild apple variety grown in Croatia were analysed for the polyphenol content and compared to two varieties grown in USA. In the flesh, flavanols, dihydrochalcones and phenolic acids (24 to 137, 23 to 109, 3 to 238 mg kg−1 of fresh weight (FW), respectively) were found. Peel contained flavanols, dihydrochalcones, phenolic acids, flavonols and anthocyanins (65 to 690, 21 to 141, 0 to 107, 205 to 1223, 0 to 213 mg kg−1 FW, respectively). The wild apple was characterized by much higher flavanol and phenolic acid content in the flesh (301 and 734 mg kg−1 FW, respectively) while the peel was similar to other apples. The polyphenol profile was similar to apples from USA. The varieties Zimnjara, Lještarka and Adamova zvijezda could be highlighted as sources of polyphenols. Varieties are categorized by the content of dihydrochalcones and flavanols in the flesh (whether that content is high or low), and by the relative portion of phenolic acids and flavanols in the flesh (high phenolic acid proportion, lower flavanol proportion and vice versa). There was not observed to be as strong a pattern for categorizing differences in the peel.  相似文献   

14.
Mercury (Hg) exposures represent a significant worldwide health issue. At the same time its content in cultivated mushrooms is not effectively regulated. The present study investigated how substrate contamination with Hg (0.1–0.5 mM) affects its accumulation in stipes and caps of Agaricus bisporus E58, Pleurotus ostreatus H195 and Hericium erinaceus HE01, mushroom growth and composition of macronutrients. The greatest Hg accumulation was demonstrated for caps. Generally, Hg uptake increased in a concentration-dependent manner and exceeded 44 mg kg−1 (P. ostreatus), 116 mg kg−1 (A. bisporus) and 53 mg kg−1 (H. ercinaceus) in caps after 0.5 mM was added to the substrate. Importantly, an increase in Hg accumulation was also significant and potentially hazardous for human health at the lowest assayed concentration. A. bisporus and P. ostreatus revealed high resistance to Hg and declined its biomass only at 0.4 and 0.5 mM concentration. The presence of Hg did not alter the macronutrient composition (total carbohydrates, proteins and fats). These results highlight the significant role of proper substrate selection in mushroom cultivation to avoid exposing consumers to harmful Hg levels and further health consequences.  相似文献   

15.
Rice and its derivatives are important source of essential and non-essential elements. Essential elements as cobalt (Co) and selenium (Se) are vital for human homeostasis. However, non-essential elements such as arsenic (As), cadmium (Cd) and lead (Pb) may be present in rice-based food and consequently, people can be exposed—especially children and the celiac population. This study aimed to determine essentials and non-essentials elements in rice-based products and baby food and also to evaluate nutritional risk by estimating the daily intake of non-essential elements. Regarding essential elements, Co and Se presented the highest concentrations in rice flour (56 μg kg−1) and porridge (254 μg kg−1), respectively. For non-essential elements, the highest concentrations of As, Cd and Pb were 104 μg kg−1 (porridge), 16 μg kg−1 (flour), and 188 μg kg−1 (bread), respectively. Total As concentration in Brazilian rice-based baby food was <29 μg kg−1. However, As-speciation revealed inorganic-As (i-As) as the main specie. The highest estimated daily intake of Cd, Pb and i-As were 1.37 (rice-based baby food); 10.39 (pasta); and 3.34 (pasta) μg d−1, respectively. Therefore, continuous food monitoring for nutritional and toxicological purpose is necessary, especially concerning these particular populations and discussions for maximum levels of non-essential elements.  相似文献   

16.
A fast and sensitive method has been developed for the determination of five fluoroquinolones and a quinolone in commercial bovine milk by capillary-LC–DAD–MS after simple extraction method based on milk deproteinization with 15% trichloroacetic acid. Separation was carried out in a Zorbax SB-C18 column (150 mm × 0.5 mm, 5 μm) using a mixture of acetonitrile–5 mM ammonium formate (pH 3.7) as mobile phase in gradient elution mode. The sample was prepared in a 5 mM aqueous ammonium formate buffer for focusing purposes and 20 μL were injected. Flow rate and temperature were set at 20 μL min−1 and 25 °C, respectively. Method validation was performed according to the European Commission Decision 657/2002/EC. Sample detection limits were between 2.8 and 25 μg kg−1, and good linearity was observed up to 250 μg kg−1 for all analytes. Acceptable and constant recoveries of 96% for enrofloxacin, 77% for its metabolite ciprofloxacin, and 64% for flumequine, with RSDs (n = 4) lower than 8%, were obtained at the 100 μg kg−1 maximum level permitted in milk. Recoveries between 70% and 83% were obtained when difloxacin, sarafloxacin and ofloxacin (not allowed in animals that produce milk for human consumption) were added to milk samples at levels in the range 75–150 μg kg−1. Decision limit (CCα), detection capability (CCβ), repeatability, within-laboratory reproducibility and robustness were compliant with European Union regulations.  相似文献   

17.
The objective of this work was the evaluation of different conditions for the selected free amino acids extraction from cheese samples, followed by capillary isotachophoresis analysis. Parameters of the extraction: concentration and type of extraction reagents (solvents: methanol, ethanol and mineral acids: perchloric acid, trichloroacetic acid, sulphuric acid and hydrochloric acid), time and temperature, and isotachophoretic separation conditions (voltage, time) were studied. Repeatability, reproducibility and stability of this method at different conditions are discussed. The best yield of free amino acids was obtained after triple extraction (30 min each process) with 0.1 M hydrochloric acid at 50 °C. Histidine, lysine, arginine, ornithine, tyrosine, and phenylalanine were determined using calibration curves and the standard additions method in different types of cheeses. The highest level of amino acids was determined in semi-hard cheese (2626.3 mg 100 g−1 – calibration curve, and 2679.2 mg 100 g−1 – standard additions method), whereas the lowest were found in sheep cheese (426.3 mg 100 g−1 and 455.7 mg 100 g−1, respectively), and Gouda type cheese samples (441.5 mg 100 g−1 and 472.8 mg 100 g−1, respectively).  相似文献   

18.
Concentrations of the macroelements Ca, Mg, K and Na, microelements Cr, Cu, Fe, Mn and Zn and toxic metals As, Cd, Hg and Pb were determined in oysters and mussels collected at farming sites in the northern, central and south Adriatic Sea. Mean concentrations in oysters were (mg kg−1): As 4.51, Ca 1551, Cd 1.44, Cu 53.6, Cr 0.23, Fe 45.9, Hg 0.047, K 2476, Mg 895, Mn 2.80, Na 7148, Pb 0.52, Zn 675. Mean values in mussels were (mg kg−1): As 4.71, Ca 601, Cd 0.37, Cu 1.91, Cr 0.29, Fe 49.6, Hg 0.026, K 2246, Mg 1043, Mn 2.49, Na 7992, Pb 0.58, Zn 28.8. Significant differences in the concentrations of toxic metals and elements were found in oysters and mussels among farming sites. Obtained Cd, Hg and Pb concentration in oysters and mussels were lower than the limit levels set by the European Community. However, Cd concentration exceeded the limit level of 1 mg kg−1 in oysters from all locations except Lim Bay. The estimated daily intakes (EDIs) indicate that oysters are a good source of Ca, Cu and Zn. The higher Cu and Zn concentrations than the toxicity reference values suggest a risk for consumers if larger quantities of oysters are consumed frequently.  相似文献   

19.
A sensitive, precise and reliable flow-batch method for the determination of aluminium (Al) was developed using a sequential injection-monosegmented flow system incorporating a mixing chamber unit. Eriochrome cyanine R (ECR) was used as a chromogenic reagent in the presence of N,N-dodecyltrimethylammonium bromide (DTAB). The Al-ECR complex at pH 6 gave a maximum absorption at 584 nm. In-line single standard calibration and a standard addition procedure were developed employing the monosegmented flow technique. Under the optimum conditions, a linear calibration graph in the range of 0.0075–0.625 mg L−1 Al was obtained with limits of detection and quantitation of 0.0020 and 0.0070 mg L−1, respectively. Relative standard deviations were 0.8 and 1.3% for 0.010 and 0.025 mg L−1 Al (n = 11), respectively. A sample throughput of 24 h−1 using an in-line standard calibration approach and 6 h−1 using four standard addition levels was achieved. The developed system was successfully applied to water samples and beverage samples. The results agreed well with those obtained from the ICP-AES method. Good recoveries between 85 and 104% were obtained.  相似文献   

20.
In this study the concentrations of K, Ca, Mg, Na, Al, Zn, Fe, Mn, Cu, Cr, Ni, Se, Pb, Cd, and As in 39 honey samples of different botanical (orange-blossom, lemon-blossom, chestnut, eucalyptus, acacia, sulla and wildflower honeys) and geographical (Sicily and Calabria, Italy) origin were determined by ICP-OES and ICP-MS. The most abundant minerals decreased in the following order: K (mean value: 1.57 mg g−1) > Ca (0.2 mg g−1) > Mg (0.121 mg g−1) > Na (0.092 mg g−1). Recommended Dietary Allowance (RDA) values and benchmark levels were employed to assess the honey quality and safety. The data excluded toxicological risks: for an adult of 60 kg, a daily intake of 2 g of honey covered maximum 0.40% of Tolerable Weekly Intake (TWI) for Al, 0.33% of Benchmark Dose of 1% Extra Risk (BMDL01) for Pb, and 0.07% of Tolerable Daily Intake (TDI) for Ni. Mineral content marks the differences in honey samples from different geographical origin despite the botanical factor weight and can be used as a tool to assess the traceability of honeys. The discrimination between Sicilian and Calabrian honeys was achieved by Principal Component Analysis (PCA), and also the results of Canonical Discriminant Analysis (CDA) indicate that the 100% of total samples are correctly classified. This research contributes to the studies to determine the geographical origin of honeys.  相似文献   

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