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81.
K. Lancova M. Kostelanska J. Kohoutkova J. Nedelnik H. Moravcova 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(5):650-659
Toxic secondary metabolites produced by fungi representing Fusarium genus are common contaminants in cereals worldwide. To estimate the dietary intake of these trichothecene mycotoxins, information on their fate during cereal processing is needed. Up-to-date techniques such as high-performance liquid chromatography (HPLC) coupled with tandem mass spectrometry (LC-MS/MS) was used for the analysis of seven trichothecenes (deoxynivalenol, nivalenol, HT-2 toxin, T-2 toxin, 15- and 3-acetyldeoxynivalenol, and fusarenon-X) in bread production chain (wheat grains, intermediate products collected during milling and baking process, breads). Regardless of whether the grains were naturally infected or artificially inoculated by Fusarium spp. in the field, the fractions obtained from the grain-cleaning procedure contained the highest mycotoxin levels. During milling the highest concentrations of deoxynivalenol were found in the bran, the lowest in the reduction flours. Baking at 210°C for 14 min had no significant effect on deoxynivalenol levels. The rheological properties of dough measured by fermentograph, maturograph, oven rise recorder, and laboratory baking test were carried out, and based on the obtained results the influence of mycotoxin content on rheological behaviour was investigated. 相似文献
82.
Waldo J. de Boer Hilko van der Voet Bas G.H. Bokkers Martine I. Bakker Polly E. Boon 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(11):1433-1449
Various models exist for estimating the usual intake distribution from dietary intake data. In this paper, we compare two of these models, the Iowa State University Foods (ISUF) model and the betabinomial-normal (BBN) model and apply them to three different datasets. Intake data are obtained by aggregating over multiple food products and are often non-normal. The ISUF and BBN model both address non-normality. While the two models have similar structures, they show some differences. The ISUF model includes an additional spline transformation for improving the normality of the intake amount distribution, while the BBN model includes the possibility of addressing covariates, such as age or sex. Our analyses showed that for two of the example datasets both models produced similar estimates of the higher percentiles of the usual intake distribution. However, for the third dataset, where the intake amount distribution appear to be multimodal, both models produced different percentile estimates. 相似文献
83.
《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(7):1020-1031
ABSTRACTIn this study, a new method was developed for simultaneously determining nine preservatives, that is, benzoic acid (BA), sorbic acid (SOA), dehydroacetic acid (DHA) and PHBAs (methyl p-hydroxybenzoate [PHBA-me], ethyl p-hydroxybenzoate [PHBA-et], isopropyl p-hydroxybenzoate [PHBA-ipro], propyl p-hydroxybenzoate [PHBA-npro]), isobutyl p-hydroxybenzoate [PHBA-ibut] and butyl p-hydroxybenzoate [PHBA-nbut]), in processed foods, employing liquid chromatography (LC). This procedure accelerated sample preparation and improved efficiency by employing modified quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction without clean-up. Samples were prepared with 20 mL of acetonitrile/water (1:1) with the assistance of a ceramic stone. The extract solutions were diluted 10 times or according to the detection amount and then injected into an LC-PDA. This method showed good linearity, and the LOQs were 10 mg/kg for BA, SOA and DHA and 5?mg/kg for the PHBAs. When validating this method, the recoveries of the nine preservatives were in the range 77.0–99.6%, RSDr values were in the range 0.7–5.3% and those of RSDwr were in the range 2.3–8.4%. These results suggest that this new method is highly reproducible. 相似文献
84.
Literature compilation of volatile N-nitrosamines in processed meat and poultry products - an update
《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(10):1491-1500
ABSTRACTA compilation of volatile N-nitrosamine levels in processed (e.g., cured, canned, smoked) meat and poultry products is presented. Over 1800 samples of processed meat products including bacon, ham, salami, sausage, and various other processed meat and poultry products have been examined for the presence of eight volatile N-nitrosamines. The database compiled from the literature is based on 25 references published for the period of 1985 to 2018 from 14 countries. N-nitrosodimethylamine (NDMA), N-nitrosopiperidine (NPIP), and N-nitrosopyrrolidine (NPYR), are the most frequently identified volatile N-nitrosamines occurring in processed meat and poultry products. N-nitrosodiethylamine (NDEA), and N-nitrosodibutylamine (NDBA) are also frequently observed to a lesser extent. The processed meat and poultry products with the highest levels of volatile N-nitrosamines were pork (fried, fat only eaten), poultry (fried), poultry (spiced, grilled), and bacon (fried). 相似文献
85.
Victoria Jackson Meera Penumetcha 《International Journal of Food Science & Technology》2019,54(6):1981-1988
Processed foods are popular and their consumption is expected to grow globally. Food processing and manufacturing promote lipid oxidation in foods rich in polyunsaturated fatty acids and cholesterol. This review focuses on how various food manufacturing/processing techniques promote lipid oxidation in grains, meats and meat products, dairy and fats/oils. This review also considers emerging evidence from animal and human studies that suggest a link between dietary oxidised lipid consumption and chronic disease risk. An update on novel food technologies that limit food lipid oxidation is discussed so as to inform both food scientists and dietitians/nutritionists to direct future efforts in not only continuing to bring these novel technologies to the market place but also conduct clinical trials to establish their role in human health. 相似文献
86.
87.
目的比较常规加热法和粉碎离心法对果冻类样品中非法添加物质的提取效果。方法以常见的2种降糖类、4种减肥类和3种利尿类非法添加化学物质为研究对象制备基质加标阳性样,样品经加热和粉碎离心处理后采用超高效液相色谱串联质谱仪测定,外标法定量,以基质效应、回收率和精密度为指标考察2种方法的提取效率。结果加热处理下样品的回收率为31.27%~135.50%,精密度为0.75%~16.40%,经粉碎离心提取处理下的样品中的9种非法添加化学药物回收率为51.60%~116.90%,精密度为1.63%~10.70%,粉碎离心处理下样品的基质效应也低于加热处理。结论相较于加热提取法,粉碎离心提取法操作简便、结果稳定可靠、灵敏度高,可用于果冻类胶质样品的样品前处理。 相似文献
88.
André F. Soares Alice R. Honorio Diana C. Nunes de Lima Alline A. L. Tribst 《International Journal of Food Science & Technology》2021,56(9):4428-4433
This study characterised the main sweet beverages and food products marketed in Brazil regarding (i) the addition of sugar/sweeteners, (ii) nutritional profile and (iii) sugar claims. Results revealed that most of the beverages had added sweeteners, while food products were mainly sweetened with sugar. Moreover, >90% of the powdered products had added sweeteners. ‘Zero sugar’ (46%) and ‘light’ (55%) were the most common sugar claims in sugar-free and reduced-sugar products, respectively. Powdered products, soya drinks and baked products included claims less frequently. Regarding the nutritional profile, beverages with sugar substitution had a proportionally greater reduction in the content of carbohydrates and calories (up to 99%, for both) in relation to food (<82% and <85%, respectively). The results suggest that reducing sugar in solid foods remains a greater challenge than in beverages and that this reduction has less impact on the final energy density of foods. 相似文献
89.
研究了热水处理对茭白的嫩度、表皮色泽、叶绿素含量的影响 .结果表明 :38℃热水处理 1h可保持茭白的嫩度、抑制表皮中叶绿素的合成、抑制细胞质膜相对透性的增加 ,研究还表明茭白采后无呼吸高峰出现 . 相似文献
90.
中国加工食品安全现状研究——基于国家质检总局2009~2012年抽查数据分析 总被引:1,自引:0,他引:1
基于国家质检总局网站上公布的2009~2012年16039个产品抽检结果的研究表明,我国加工食品监督抽查合格率从2009年的91.1%上升至2012年的95.6%:抽查结果中1024种不合格加工食品的生产企业分布在全国30个省直辖市自治区,排名前三的地区为广东、山东、河北;理化指标不合格、微生物指标不合格、超范围使用食品添加剂和化学污染物超标是我国加工食品存在的主要问题。通过分析发现,我国加工食品整体抽查合格率仍不高,抽检中不合格加工食品来自经济较发达地区的情况较多,食用油、调味品、膨化食品、豆制品等食品类别不合格率较高,造成我国加工食品不合格的主要食品安全问题是化学性有害因素,其次是生物性有害因素。 相似文献