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ABSTRACTA 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
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We studied the stability of the valuable vitamer nutrients α-tocotrienol and α-tocopherol and options for their protection in salami-type sausages (blended with α-tocotrienol-rich barley oil) and curing brine. Four different sausage formulations were produced containing nitrite curing salt; nitrite curing salt and ascorbic acid (300 mg/kg); nitrite curing salt and carnosic acid (45 mg/kg); or sodium chloride. Initial vitamer contents (100 mg/kg) did not decrease significantly during ripening and decreased only slightly during storage. Ascorbic acid and carnosic acid were found to be effective in preserving the vitamers in fresh sausages. Freeze-drying of sausages resulted in a significant loss of vitamers (97%), particularly after 14-day storage at room temperature, even in the presence of shielding gases. The vitamer content in the curing brine decreased with decreasing pH in the presence of nitrite. A nitrite concentration of 136 mg/L at pH 4 resulted in significant loss (90%) of the vitamers. Sufficient stability of the vitamers in salami-type sausage and curing brine can be achieved by processing, formulation, and storage conditions. 相似文献
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Kit Granby Nikoline Juul Nielsen Rikke V. Hedegaard Tue Christensen Mette Kann Leif H. Skibsted 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(8):921-929
Acrylamide in baked and toasted wheat and rye bread was studied in relation to levels of asparagine in flour, dough, bread and toasts. Asparagine was consumed during bread preparation resulting in reduced acrylamide content in the products. In wheat bread, 12% of the asparagine initially present in the flour (0.14 g kg?1) remained after yeast fermentation and baking; for rye bread, 82% of asparagine remained after sourdough fermentation and baking. Asparagine present in untoasted wheat bread had totally reacted after hard toasting. Toasted wheat and rye bread slices contained 11–161 and 27–205 µg kg?1 acrylamide, respectively, compared to untoasted wheat and rye bread with <5 and 7–23 µg kg?1 acrylamide, respectively. The dietary intake of acrylamide from bread (untoasted) of 2 µg day?1 is relatively low; however, acrylamide exposure from bread increases several fold for people eating toasted bread. 相似文献
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Concurrent phase separation and gelation in mixed oat β-glucans/sodium caseinate and oat β-glucans/pullulan aqueous dispersions 总被引:1,自引:0,他引:1
The phase separation behavior of mixed oat β-glucans/sodium caseinate and oat β-glucans/pullulan aqueous dispersions at 20 °C has been studied. The concentration of β-glucans required for induction of phase separation and the physical state of the separated phases, as revealed by visual observations and dynamic rheometry, depended on the molecular weight of β-glucans and the initial polymeric composition. For β-glucans with apparent molecular weights (Mw) 35 and 65 × 103 the β-glucan concentration at which thermodynamic incompatibility occurred decreased from about 2–2.5% (w/w) at low concentrations (∼0.2%) of sodium caseinate or pullulan to about 1–1.5% (w/w) β-glucans at high levels (up to 7.5% w/w) of the second biopolymer; these bi-phasic systems consisted of an upper liquid phase and a lower gel-like phase. For β-glucans with Mw of 110 × 103, a bi-phasic system with two liquid phases appeared above a certain β-glucan concentration, which decreased from approximately 4% to 1% (w/w) with increasing sodium caseinate levels in the range of 0.2–7.5% (w/w). With further increase in β-glucan concentration, the lower phase turned into a gel, and at even higher β-glucan concentrations, the polymer demixing process was ‘arrested’ by chain aggregation events, leading to a macroscopically single gel phase. Generally, the aggregation of β-glucans seemed to interfere with the phase separation phenomenon resulting in an increase of β-glucan concentration in the lower phase between 5% and 110% and only a slight increase of sodium caseinate or pullulan concentration in the upper phase (<10%), due to kinetic entrapment of the polymeric components into a highly viscous medium. 相似文献
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Unsanitary conditions during harvesting, drying, packing and storage stages in production and processing of spices and herbs could introduce mycotoxin contamination. The occurrence of ochratoxin A and fumonisins in popular spices and herbs was studied, using liquid chromatography-electrospray-mass spectrometry. Apart from mycotoxins, ergosterol as a factor indicating fungal development was also analysed. A total of 79 different samples commercialized in Poland were randomly purchased from popular markets were tested for mycotoxins. The frequency of samples with fumonisins was lower (31%) than ochratoxin A (49%). Free from mycotoxins were samples of bay leaf and white mustard. ERG content – in spice samples with high concentration level of mycotoxins – was also significantly higher than in samples with little to no mycotoxins. 相似文献
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José Fernando Huertas-Pérez Marion Ernest 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2019,36(1):109-119
Two methods based on a modified QuEChERS sample preparation and either LC coupled to atmospheric pressure ionisation and high-resolution MS or GC coupled to electron ionisation and tripled quadrupole MS have been assessed for the quantification of folpet and phthalimide in tea and other dry herbal infusions. Both methods have been fully validated in green tea and further checked in black tea, verbena and rooibos, and they performed according to the SANTE/11813/2017 criteria at the target LOQ concentration level (50 µg/kg). These methods allow the accurate quantification of folpet in the selected matrices according to the new EU residue definition, which includes phthalimide. Phthalimide is the main metabolite and degradation product of folpet, although according to recent studies, it could be generated from different sources than folpet breakdown, such as food processing or analysis by GC. 相似文献
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Berries and red fruits are rich dietary sources of polyphenols with reported health benefits. More than 50 different flavonols (glycosides of quercetin, myricetin, kaempferol, isorhamnetin, syringetin and laricitrin) have been detected and quantified with HPLC–MSn in fruits of blueberry, bilberry, cranberry, lingonberry, eastern shadbush, Japanese wineberry, black mulberry, chokeberry, red, black and white currants, jostaberry, red and white gooseberry, hardy kiwifruit, goji berry, rowan, dog rose, Chinese and midland hawthorn, wild and cultivated species of blackberry, raspberry, strawberry and elderberry. The phenolic constituents and contents varied considerably among the analyzed berry species. Elderberry contained the highest amount of total flavonols (450–568 mg kg−1 FW), followed by berry species, containing more than 200 mg kg−1 FW of total: chokeberry (267 mg kg−1), eastern shadbush (261 mg kg−1), wild grown blackberry (260 mg kg−1), rowanberry (232 mg kg−1), american cranberry (213 mg kg−1) and blackcurrants (204 mg kg−1). Strawberry (10.5 mg kg−1) and white currants (4.5 mg kg−1) contained the lowest amount of total flavonols. Quercetins represent the highest percentage (46–100%) among flavonols in most analyzed berries. In wild strawberry and gooseberry the prevailing flavonols belong to the group of isorhamnetins (50–62%) and kaempferols, which represent the major part of flavonols in currants (49–66%). Myricetin glycosides could only be detected in chokeberry, rowanberry and species from the Grossulariaceae, and Adoxaceae family and Vaccinium genus. Wild strawberry and blackberry contained from 3- to 5-fold higher total flavonols than the cultivated one. 相似文献
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The induction of α- and β-galactosidases in six strains of Lactobacillus reuteri (L. reuteri) by six carbohydrate sources and four protein sources was studied. L. reuteri grown on raffinose had the highest α-galactosidase activity (10.55 Gal U/ml), while lactose exhibited the highest β-galactosidase activity (43.82 Gal U/ml) when compared to other carbohydrate sources. L. reuteri grown on yeast extract exhibited the highest α- and β-galactosidases activity (15.27 and 12.88 Gal U/ml, respectively) when compared to other protein sources. MF14C and SD2112 grown on raffinose had the highest α-galactosidase activity (14.75 and 14.18 Gal U/ml, respectively) followed by CF2-7F (13.38 Gal U/ml). CF2-7F grown on lactose had the highest β-galactosidase activity (82.01 Gal U/ml). SD2112, MM2-3 and CF2-7F grown on yeast extract (20.96, 19.67, 19.67 Gal U/ml, respectively) showed the highest α-galactosidase activity. MM2-3 and CF2-7F grown on yeast extract showed the highest β-galactosidase activity (18.1 and 17.59 Gal U/ml, respectively). Raffinose and lactose were the best carbohydrate sources to produce α- and β-galactosidases, respectively. Yeast extract was the best protein source to produce both enzymes and CF2-7F strain was the best producing strain on all tested conditions. 相似文献
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Leonardo Di Donna Domenico Taverna Fabio Mazzotti Hicham Benabdelkamel Mohamed Attya Anna Napoli Giovanni Sindona 《Food chemistry》2013
Flavanones, a class of flavonoids present in large amounts in fruits and vegetables, have been assayed by LC–MS/MS and derivatization chemistry using d0/d3-labelled derivatized internal standards obtained by simple reaction procedures which involves d0/d3 methoxyamine. The assay method considers 13 flavanones including aglycones, neohesperidosides, rutinosides and 3-hydroxy-3-methyl glutaryl derivatives. The strengths of the method consist in a relative short analysis time (16 min) and good repeatability and reproducibility values which are in most cases under 10% (RSD%). The accuracy values range from 95.4% to 111.3% whilst the LOQ values ranges from 0.05 to 0.29 mg/L depending on the analyte. 相似文献
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Rogério A. Curi Luis Artur L. Chardulo Juliana Giusti Antonio C. Silveira Cyntia L. Martins Henrique N. de Oliveira 《Meat science》2010
The objective of this study was to investigate the effects of bovine GH1, CAPN1 and CAST gene polymorphisms on carcass and meat traits in Nellore and Nellore x Bos taurus beef cattle. Three hundred animals were genotyped for GH1/MspI (TC/G in intron 3), CAPN316 (AF_252504.2:g.5709C > G) and CAST/RsaI (AY_008267.1:g282C > G) and phenotyped for rib eye area, backfat thickness, intramuscular fat, shear force (SF), and myofibrillar fragmentation index (MFI). No significant associations were observed between the GH1/MspI and CAST/RsaI polymorphisms and phenotypes, although the relation between the CAST/RsaI genotypes and meat tenderness evaluated by MFI approached significant. The fact that the CAPN316 polymorphism did not show adequate segregation in Nellore cattle confirms the difficulty of using this marker in breeding programs of different Bos indicus breeds. However, the positive results of the association analysis obtained for Nellore x B. taurus crosses contributed to the validation of previous findings. 相似文献
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The study concerns the interactions between (+)-catechin and a representative oak wood aldehyde (5-(hydroxymethyl)furfuraldehyde for furanic aldehydes and vanillin for phenolic aldehydes) in a wine-like model solution in presence or not of SO2. The formed condensation products were characterised by LC/MS, LC/ESI/MSn, and ESI/HR/MS and we studied the effect of SO2 on these condensation reactions. 相似文献
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The experiment was undertaken to provide information of the influence of feeding either free-range or in confinement with different dietary MUFA/PUFA ratios and α-tocopheryl acetate supplementation (40 vs. 200 mg/kg) on tocopherol content and susceptibility to lipid oxidation of muscle and microsomes in Iberian pigs. The grass provided to the pigs had a similar α-tocopherol concentration to that observed for diets supplemented with 200 mg/kg α-tocopheryl acetate, and acorns supplied fourfold higher content of γ-tocopherol than the experimental diets. The α- and γ-tocopherol contents of muscle reflected the tocopherol concentration of the diets. Mono and Medium diets produced a similar MUFA/PUFA ratio in neutral and polar lipids of pig muscle to those fed outdoors. The lowest TBARS numbers were found in muscle samples from pigs fed a MUFA-enriched diet in confinement. No significant influence of free-range feeding or dietary fat on drip loss was found. However, α-tocopheryl acetate supplementation reduced (P<0.05) drip loss. Dietary vitamin E supplementation decreased the membrane lipid oxidation by 18% after 120 min. However, free-range feeding decreased the extent of microsome oxidation by 20%, 56% and 82% after 120 min when compared with those groups fed in confinement with high, medium and low MUFA/PUFA ratios, respectively. The hexanal concentration of muscle showed a similar trend to that observed for microsome induced-oxidation, suggesting, that hexanal determination is a more accurate method to measure lipid oxidation in iberian pig muscle than the thiobarbituric acid test. 相似文献
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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
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《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
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Kevin Tran David Eide Susan M. Nickols Michele R. Cromer Armando Sabaa-Srur Robert E. Smith 《Food chemistry》2012
Products labelled as containing extracts from two mushrooms (cordyceps plus reishi) and the juices from açaí, goji, mangosteen, noni, pomegranate, and sea buckthorn have been analysed for 174 different pesticides, using the validated QuEChERS method for sample preparation and electrospray LC–MS/MS in the positive ion mode for analysis. Pesticides were found in 10 of the 21 samples analysed. Most pesticides found were below the tolerance levels (1–6 μg/g, depending on the pesticide), but some were not. This included boscalid, dimethomorph, iprovalicarb, pyridaben, pyrimethanil, and imazalil, for which there is no tolerance reported or zero tolerance in any fruit. However, genuine açaí that was harvested in the state of Pará and lyophilised in Rio de Janeiro had no detectable pesticides, when analysed by both LC–MS/MS and GC–MS/MS, which can detect 213 more pesticides and industrial chemicals. Likewise no pesticides were found in one sample each of cordyceps plus reishi, sea buckthorn and noni. 相似文献
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Mimoza Basholli-Salihu Monika Mueller Sharareh Salar-Behzadi Frank M. Unger Helmut Viernstein 《LWT》2014
The benefit of disaccharide protectants for maintaining viability and β-glucosidase activity of Bifidobacterium infantis UV16PR during freeze-drying and storage in different food matrices was investigated. Protectants used were cellobiose, lactose, sucrose and trehalose. 相似文献
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The objective of this experiment was to determine whether source of supplemental α-tocopherol fed to periparturient dairy cows affects neutrophil function and vitamin E status of the cow and the neonatal calf. Starting 14 d before anticipated calving and continuing until 14 d post-parturition, cows were fed diets with no supplemental vitamin E or with 2,500 IU/d of vitamin E from all-rac α-tocopheryl acetate or RRR α-tocopheryl acetate. All-rac α-tocopherol contains equimolar amounts of all 8 stereoisomers, whereas the RRR contains only the RRR isomer. Concentrations of α-tocopherol in cow plasma, colostrum, milk, and blood neutrophils were greatest for the RRR treatment, intermediate for all-rac, and lowest for cows fed no supplemental vitamin E. The concentration of α-tocopherol in plasma of newborn calves was very low and not affected by treatment but after 6 feedings of their dam's colostrum or milk, concentrations in calf plasma followed the same treatment pattern as cow plasma. The number of bacteria phagocytized was greater by neutrophils from cows fed all-rac vitamin E than for the other 2 treatments, which resulted in a greater number of bacteria being killed. For cows fed all-rac vitamin E, the RRR isomer comprised about 20% of the α-tocopherol consumed but approximately 60% of the α-tocopherol in plasma and milk. This enrichment was caused mostly by an almost complete discrimination against the 2S isomers. Because all-rac α-tocopherol is 50% 2S isomers, these data suggest that 1 g of all-rac tocopheryl acetate is equivalent to 0.5 g of RRR tocopheryl acetate. 相似文献