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An LC-MS/MS multi-method was developed to simultaneously quantify ergot alkaloids (EAs) and tropane alkaloids (TAs) in 113 cereal-based food for infants and young children. To assess yearly variation, samples were collected in 2011, 2012 and 2014. EAs were detected in 54% and TAs in 22% of the samples. Mean EA levels in the three sampling years were 10.6, 6.2 and 8.6 µg kg?1, respectively (maximum: 115.4 µg kg?1), indicating that exposure to EAs would not have exceeded the health-based guidance values set by EFSA in 2012. Mean TA levels were 3.9, 2.4 and 0.4 µg kg?1, respectively (maximum: 80.8 µg kg?1). The acute reference dose for TAs, derived by EFSA in 2013, would have been exceeded by young children when consuming some of the products sampled in 2011–2012. TA levels had decreased drastically in 2014, possibly due to measures taken by producers as response to the EFSA Opinion.  相似文献   

3.
《Food chemistry》1986,19(2):93-104
A method is described for the lowering or removal of the metal content of wines. For this purpose, a chelating material is employed, formed from cellulose functionalized with iminodiacetic acid. Its use allows, first, a preconcentration of metals present at trace levels and, secondly, a lowering or removal of undesirable metals. Possible matrix effects, both by organic and inorganic components, have been considered and allowed for in the analytical determination.  相似文献   

4.
Aflatoxin M1 (AFM1) occurrence was analysed in 80 samples of milk and 21 samples of infant formulae on the Serbian market, using high-performance liquid chromatography with fluorescence detection. All milk samples collected in 2013 showed AFM1 contamination in the range 0.02–0.32 μg kg?1, with a mean level of 0.13 μg kg?1. The EU maximum level for AFM1 in milk (0.05 μg kg?1) was exceeded in 75% of the samples. In 2014, AFM1 was found in 83%, 70%, 80% and 58% of the samples collected in April, July, September and December, respectively, exceeding the limit in 5% of the samples taken in July. The additional number of liver cancer cases per year associated with exposure to AFM1 was estimated to be 0.004 in the adult population. Regarding infant formulae, AFM1 was found in only one sample.  相似文献   

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The occurrence of aflatoxins (AF) B1, B2, G1, G2 and cyclopiazonic acid (CPA) in feeds, and AFM1 and CPA in milk was determined in dairy farms located in the northeastern region of São Paulo state, Brazil, between October 2005 and February 2006. AF and CPA determinations were performed by HPLC. AFB1 was found in 42% of feed at levels of 1.0–26.4 µg kg?1 (mean: 7.1 ± 7.2 µg kg?1). The concentrations of AFM1 in raw milk varied between 0.010 and 0.645 µg l?1 (mean: 0.104 ± 0.138 µg l?1). Only one sample was above the tolerance limit adopted in Brazil (0.50 µg l?1) for AFM1 in milk. Regarding CPA in feed, six (12%) samples showed concentrations of 12.5–153.3 µg kg?1 (mean: 57.6 ± 48.7 µg kg?1). CPA was detected in only three milk samples (6%) at levels of 6.4, 8.8 and 9.1 µg l?1. Concentrations of aflatoxins and CPA in feed and milk were relatively low, although the high frequency of both mycotoxins indicates the necessity to continuously monitor dairy farms to prevent contamination of feed ingredients.  相似文献   

7.
ABSTRACT

A survey on the occurrence of acrylamide (AA) in roasted coffee, barley, and potato crisps was carried out using an intra-lab validated liquid chromatography (LC)–MS (mass spectrometry)/MS method. Over the years 2015–2016, 66 samples of coffee, 22 of roasted barley, and 22 of potato crisps were collected from retail outlets in Italy. AA was detected in almost all samples. In roasted coffee, the level exceeded 450 µg kg?1, the limit recommended by the European Commission (EC), in 36.4% of the samples. In roasted barley, mean contamination was slightly lower than in coffee and no sample exceeded the EC limit of 2000 µg kg?1. The AA contamination in potato crisps was remarkable. A percentage of 36.4 (n = 8) showed a value higher than the EC limit of 1000 µg kg?1. Considering the average consumption of coffee and potato crisps by Italian people, AA exposure is significant and should be decreased.  相似文献   

8.
Dry-cured bacons were processed using pig bacon belly as material by dry-salting and drying–ripening. Lipolysis and lipid oxidation in intramuscular lipids were studied by evaluating the changes in lipid composition, lipolytic enzymes and lipoxygenase (LOX) activities, peroxide value (POV) and TBARS during processing. Lipid composition showed a significant decrease (< 0.05) in phospholipids and an increase (< 0.05) in free fatty acids (r = −0.85, p = 0.0004). All lipolytic activities decreased (< 0.05) with increasing process time. Acid lipase showed higher activity than did neutral lipase (< 0.05) throughout the processing. LOX activity increased significantly during salting (< 0.01) and thereafter decreased. High salt content inhibited acid lipase and phospholipase activities but promoted LOX activity. Both POV and TBARS decreased (< 0.05) with temperature rising during the last ripening period, suggesting that rising temperature in this period could lower oxidation indices in products. LOX was closely correlated with TBARS (r = 0.94) but not with POV (r = 0.36), indicating that LOX could facilitate lipid secondary oxidation.  相似文献   

9.
Guaraná powder is an antiobesogenic supplement; however, its effect on inflammatory biomarkers has not yet been determined. Therefore, this study analysed whether guaraná supplementation can differentially modulate the levels of proinflammatory cytokines [interleukin 6 (IL-6), tumour necrosis factor-alpha, interleukin 1 beta (IL-1β), interferon-gamma (Ig-γ)] and anti-inflammatory interleukin 10 (IL-10) from in vitro and in vivo protocols. In the pilot in vitro protocol, human peripheral blood mononuclear cells were exposed to guaraná, as well as to resveratrol, quercetin and ascorbic acid as positive controls. The effect of guaraná on cytokine levels was also evaluated in culture medium supplemented with glucose and insulin. A randomised, placebo-controlled in vivo assay was also performed to evaluate the potential influence of guaraná on the blood cytokine levels of 14 healthy volunteers supplemented for 14 days. The effect of guaraná was similar to that of resveratrol, a known anti-inflammatory molecule, decreasing IL-1β, IL-10 and Ig-γ levels and increasing IL-10 levels compared to those of the control group. The in vitro insulin supplementation potentiated the effect of guaraná on some cytokines. A decreasing effect on the blood inflammatory cytokine levels, along with an increase in IL-10 levels, was also observed in volunteers supplemented with guaraná. In conclusion, guaraná positively modulates cytokines associated with inflammatory metabolism.  相似文献   

10.
《International Dairy Journal》2003,13(2-3):191-200
Three batches of Pecorino del Poro, ewes’ cheese made from raw milk, were examined throughout a 28-day ripening time at three different seasons. High logarithmic counts per gram of cheese for mesophilic coccal-shaped lactic acid bacteria (6.70–12.45), mesophilic lactobacilli (4.82–11.73), thermophilic coccal-shaped lactic acid bacteria (2.30–9.90), and thermophilic lactobacilli (2.95–8.15) were found. Coccal-shaped lactic acid bacteria were the dominant microorganisms throughout ripening. The microorganisms used as an indicator of hygiene during manufacture of the cheeses, coliforms and Escherichia coli, were considerably lower, as were enterococci and yeasts. Coliforms and E. coli decreased sharply throughout ripening. Physico-chemical parameters such as pH (5.07–7.03), dry matter (46.34–72.79%), ether extract (31.35–51.84% of dry matter), crude protein (29.93–44.73% of dry matter), and chloride content (2.36–4.11% of dry matter) were also determined. Probably, the use of selected autochthonous mesophilic lactococci as a starter would control or suppress the growth of undesirable microorganisms. The results obtained suggest the need for improvements in milking and dairy conditions.  相似文献   

11.
Asparagus is often infected by fungi of the Fusarium genus, a causal agent of crown and root rot, which decreases the quantity and quality of spears. Fusarium oxysporum and Fusarium proliferatum are the most severe asparagus pathogens, well known as mycotoxin producers, mainly fumonisins and moniliformin. The present study was undertaken to estimate fumonisin B1, moniliformin and ergosterol concentrations in asparagus tissue. Moreover, the possibility of toxin transport to the edible asparagus part during the inoculation by F. oxysporum and F. proliferatum of different plant parts (root, crown and stem base) and the potential risk for consumers were assessed. Our studies showed that the highest capability of producing fumonisin B1 and moniliformin was demonstrated from isolates of F. proliferatum. The highest level of fumonisin B1 in edible spears was detected when the asparagus crown was inoculated with F. oxysporum and F. proliferatum. The lowest concentration was found in the case of storage root inoculation, which corresponds with mycelium absence and the long distance from the roots to the stem. Similar results were demonstrated for moniliformin. The mycotoxin content was confirmed even in healthy spears (without disease symptoms and mycelium presence), which might indicate that the transport of mycotoxins is possible from the soil through the root system to the top part of the plants.  相似文献   

12.
A study is reported in which fibre-length measurements were made on fibres withdrawn from a range of staples representing 21 sale lots of merino wool. The average variance of fibres within staples was 2.2 cm2, and the estimates fell in the range 1.2–4.8 cm2. Fibre-length variances within sale lots were estimated for six sale lots, and these ranged from 3.3 to 5.8 cm2.

Both the ratio of average fibre length to staple length and the regression coefficients for these parameters varied over a wide range (e.g., from 1.1 to 1.6 for the ratios and from 0.4 to 1.0 for the regression coefficients). This variation, coupled with relatively low correlation coefficients, indicates that the use of staple length as a predictor of the average fibre length of greasy wool is inefficient. However, staple length may be a useful predictor of the average fibre length of wool tops.  相似文献   

13.
Microplastic in terrestrial ecosystems and the soil?   总被引:18,自引:0,他引:18  
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14.
Grapefruit phytochemicals (β-carotene and flavonoids) stability after different jam processing was evaluated. Osmotic dehydration, microwave energy and conventional heating techniques have been used to obtain jam. β-Carotene and individual flavonoids were analyzed by HPLC technique. The results showed that jam obtained from osmodehydrated fruit (ODJ) is the only that preserved completely the β-carotene content. All processes of production of jam significantly decreased the content of narirutin (NAT), poncirin (PON), naringenin (NAG) and quercetin (QUER), while naringin (NAR) remained stable. Jams obtained by applying a heat treatment showed significant lower values of NAG and QUER in comparison with ODJ. The jam obtained from osmodehydrated fruit, without being submitted to any heat treatment, showed at the end of storage the highest contents of naringin, hesperidin, neohesperidin, didymin, quercetin, poncirin and the total sum of analysed flavonoids. In general, the phytochemical loss in jams as a consequence of processing was lower than those provoked by storage effect.  相似文献   

15.
Spices and herbs have been used since ancient times as flavor and aroma enhancers, colorants, preservatives, and traditional medicines. There are more than 30 spices and herbs of global economic and culinary importance. Among the spices, black pepper, capsicums, cumin, cinnamon, nutmeg, ginger, turmeric, saffron, coriander, cloves, dill, mint, thyme, sesame seed, mustard seed, and curry powder are the most popular spices worldwide. In addition to their culinary uses, a number of functional properties of aromatic herbs and spices are also well described in the scientific literature. However, spices and herbs cultivated mainly in tropic and subtropic areas can be exposed to contamination with toxigenic fungi and subsequently mycotoxins. This review provides an overview on the mycotoxin risk in widely consumed spices and aromatic herbs.  相似文献   

16.
Air and precipitation samples were collected in three stations located in Quebec between January 1993 and March 1996 to determine spatial and seasonal variations of several organochlorine pesticides and metabolites (alpha-HCH, gamma-HCH, HCB, gamma-chlordane, DDT, DDE, Mirex). alpha-HCH, gamma-HCH, and HCB were more or less measured in large amounts at all sites, whereas gamma-chlordane, DDT, and DDE concentrations were lower and Mirex was undetectable. Higher concentrations levels were observed in air during hot spring/summer periods except for HCB, indicating a probable temperature dependence. Ln concentrations vs reciprocal temperature plots and Henry's law determinations helped to highlight the contribution of soil and/or water volatilization of those compounds. Itwas observed that alpha-HCH came mainly from Atlantic Ocean volatilization at Mingan, whereas sources of gamma-chlordane and DDE were mostly due to volatilization from soils in southern Quebec. DDT may be present in the atmosphere by the way of transport from remote regions. Lindane sources were multiple: it may be found in the atmosphere bythe processes of transport and volatilization coming from soil or water. Finally, a negative correlation between HCB and air temperature implies that processes other than volatilization are involved in transport of this compound.  相似文献   

17.
Deoxynivalenol-3-β-D-glucoside (D3G), a phase II plant metabolite of the mycotoxin deoxynivalenol (DON), occurs in naturally Fusarium-contaminated cereals. In order to investigate the frequency of occurrence as well as the relative and absolute concentrations of D3G in naturally infected cereals, 23 wheat samples originating from fields in Austria, Germany and Slovakia as well as 54 maize samples from Austrian fields were analysed for DON and D3G by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Both analytes were detected in all the 77 field samples. DON was found at levels from 42 to 4130 ng g?1 (977 ± 1000 ng g?1 on average). The D3G concentrations in all cereal samples were in the range 10–1070 ng g?1 (216 ± 253 ng g?1 on average), corresponding to about 5–46 mol% of their DON concentrations (15 ± 8 mol% on average).  相似文献   

18.
New options to process dairy products by means of new single unit operations or combinations thereof are presented. The innovative possibilities discussed in this paper mainly refer to novel ways of influencing product microstructures or textures as perceived during consumption, by means of contributions of single molecule fractions of complex systems derived from membrane fractionation techniques. In addition, options to integrate physiologically active components which also have a structure forming effect in fermented or other dairy products are highlighted. Alternatives derived from thermal, mechanical and enzymatic processing and from fractionation techniques by means of membranes are presented which can be exploited for fractionation and compositional matrix design of dairy products.  相似文献   

19.
Wine and beer consumption are an integral part of European culture: Southern Europe is associated with wine and Northern Europe is associated with beer. When consumed in moderation, these alcoholic beverages can be part of a balanced and healthy diet. In the 1990s, non-alcoholic beer (NAB), which has no cultural roots, became available in the market. This review identifies determinants for consumption of wine, beer, and NAB, using data on consumption patterns from Portugal and the Netherlands. Since the 1960s the image of Portugal as a wine country declined, whereas the image of the Netherlands as a beer country remained stable. In each country beer is now the most consumed alcoholic beverage and is mainly a men's beverage, whereas wine is the second most consumed and is consumed by both genders. Cultural differences define Portuguese as “outdoors, everyday drinkers”, within a meal context, and Dutch as “at home, weekend drinkers.” Wine is perceived as the healthiest beverage, followed by NAB, and regular beer. Motivation for consumption is related to context: wine for special occasions, beer for informal occasions, and NAB for occasions when alcohol is not convenient. Moderate wine and beer consumption seems to be surrounded by positive emotions.

This review is relevant for public health, for industry market strategies, and identifies opportunities of future research on drinking behaviour.  相似文献   


20.
The objectives of this study were to assess antibody and cellular immune responses in first-lactation dairy heifers reared under a pasture-based production system and to investigate associations between immune competence and stress responsiveness, health, and productivity. A commercial vaccine was used to induce antibody and cellular immune responses and, based on measured responses, animals were classified as above average, average, and below average for each trait independently and in combination (overall immune competence). Overall immune competence phenotypic rankings were generated by combining standardized residual values for antibody and cellular responses measured in individual heifers. Cortisol responses to handling and yarding were used to assess stress responsiveness, worm egg counts were used to assess internal parasite burden, somatic cell counts to assess udder health and estimates of total daily milk volume, and milk fat and milk protein contents to assess productivity. A total of 393 Holstein-Friesian and Holstein-Friesian × Jersey crossbred heifers from 2 herds practicing seasonal calving in a pasture-fed production system were enrolled in the study. The immune competence phenotypes of individual heifers were assessed before their first mating and their subsequent performance during their first lactation was monitored. Animals with below-average antibody and cellular immune competence had higher serum cortisol concentrations compared with their counterparts following handling, suggesting they had a reduced ability to cope with management-induced stress. Furthermore, a significant negative (favorable) correlation was observed between antibody responses and stress responsiveness. Similarly, correlations between antibody responses and internal parasite burden were significant and negative (favorable). No correlations were observed between overall immune competence and milk yield, milk fat, and milk protein content.  相似文献   

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