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1.
Saint-Paulin, a French semihard cheese, was manufactured from milk with and without added NO3
–. Reference and experimental cheeses were analysed at different stages of ripening for the presence of apparent total N-nitroso compounds (ATNC) by chemical denitrosation and chemiluminescence detection (thermal energy analyser). The fate of
NO3
– and NO2
–was also scrutinized. The levels of ATNC and of volatile N-nitrosamines were followed during ripening. After 60 days of ripening, ATNC were detected at concentrations of 27 μg NO-N/kg
and 64 μg NO-N/kg in the cheeses obtained from milk with and without added NO3
–, respectively. The NO3
– contents of both cheeses were nearly the same, and below 5 mg/kg. The occurrence of NO2
–was not observed. No relationship was found between the NO3
– contents and the contamination of the cheeses by volatile N-nitrosamines. At the beginning of ripening, the cheeses manufactured with added NO3
- showed high levels of ATNC (mean value 5800 μg N-NO/kg with large variations of 570–15210 μg NO-N/kg). These ATNC contents
rapidly decreased during the first days of ripening (96%), but decreased much more slowly during the following days. An hypothetical
mechanism, attempting to explain the disappearance of ATNC, involving the formation of alkylated species in the cheese was
proposed.
Received: 30 March 1998 / Revised version: 7 October 1998 相似文献
2.
The fermented foods yoghurt, bread and cheese were analysed for the presence of apparent total N-nitroso compounds (ATNC) by a group-selective procedure involving direct chemical denitrosation and chemiluminescence detection of the released nitric oxide. The levels of ATNC were below the 20 micrograms(N-NO)/kg detection limit in all 20 yoghurts, 23 of the 24 bread samples and 28 out of 31 different varieties of cheese analysed. ATNC were detected in most of those cheese samples manufactured with added nitrate, including Edam, Gouda and Havarti, in concentrations ranging from 30 to 210 micrograms(N-NO)/kg. 相似文献
3.
Twenty-five smoked and unsmoked fried bacon samples have been analysed by a group selective procedure to measure the concentration of apparent total N-nitroso compounds (ATNC). The levels of a range of individual N-nitroso compounds, including simple volatile N-nitrosamines, N-nitrosothiazolidines, N-nitrosamino acids and N-nitrosothiazolidine carboxylic acids have also been examined. Concentrations of ATNC varied from 430 to 6800 micrograms(N-NO)/kg with a mean of 2700 micrograms(N-NO)/kg. Protein-bound N-nitrosoproline was the most abundant compound detected in unsmoked bacon, mean 260 micrograms/kg, and on average accounted for 4% of the ATNC concentration. For smoked bacon, bound N-nitrosoproline was detected in levels of up to 890 micrograms/kg and contributed 5% to the ATNC total. The most abundant compound present in smoked bacon was N-nitrosothiazolidine-4-carboxylic acid, mean 660 micrograms/kg, and this accounted for 6% of the ATNC. N-Nitrosothiazolidine, mean 340 micrograms/kg, and 2-(hydroxymethyl)-3-nitrosothiazolidine-4-carboxylic acid, mean 180 micrograms/kg, were the next most prominent compounds detected in smoked bacon. The combined sum of all the individual N-nitroso compounds measured accounted for, on average, 16% of the total ATNC. The identities of the N-nitroso compounds comprising the majority of the ATNC in bacon remain unknown. 相似文献
4.
Methodologies used to assess N-nitroso compounds as a group by chemical denitrosation with hydrogen bromide in glacial acetic acid have been described. Carrying out these analyses without precautions can cause considerable variations in results. Some pitfalls must be avoided in order to obtain valuable results and accurate interpretations. 相似文献
5.
The apparent total N-nitroso content of foods can be measured by a procedure based on chemical denitrosation and chemiluminescent detection of the eliminated nitric oxide. Procedures have been established which substantially reduce the 'apparatus blank' response to the denitrosating agent and allow total nitroso contents down to 10 micrograms (N-NO)/kg to be measured reproducibly on a 1-g sample. Typically, duplicate analyses of samples containing 10-1000 micrograms (N-NO)/kg differ by less than 15% of their mean. Potentially the method can be subject to some interference from compounds other than N-nitroso compounds, but at least in some commodities these interfering compounds do not exist in measurable amounts. 相似文献
6.
C L Walters 《Food Additives & Contaminants》1992,9(5):441-447
The stabilities of nitrate and nitrite in food systems and their reactions in such matrices are reviewed. Particular reference is made to reactions with haem proteins, smoke components and amines in foods, and the chemistry of formation of N-nitroso compounds from food components is discussed. Finally, the methodology available for determination of both volatile and non-volatile N-nitroso compounds is addressed. 相似文献
7.
Enzymic hydrolysis was employed to solubilize 35% of the total N-nitroso compounds associated with bacon adipose connective tissue. Size exclusion chromatography of the digest showed that 95% of the solubilized N-nitroso compounds had molecular weights equivalent to those of di-, tri- and tetrapeptides. The likely identity of these compounds is discussed in the light of their extractability from acidified solution into ethyl acetate and their thermal and pH stability. 相似文献
8.
从N-亚硝基化合物来源出发,对食品中N-亚硝基化合物的危害,机理进行综合分析,并提出预防和控制食品中N-亚硝基化合物的具体措施,为进一步提高人们对食品安全的正确认识,提供科学的参考. 相似文献
9.
MARCELA ARANDA IVAN TRIVINO ANGELICA OSORIO JOSE M. BASTIAS ORIETA ROOS 《International Journal of Food Science & Technology》1992,27(4):385-390
Chilean hams and sausages were analysed for the presence of nitrosodimethylamine and nitrosodiethylamine by GLC/NPD. The presence of 3.5–210ppb levels were found in 51.6% of the samples. All of the positive samples contained nitrosodimethylamine while only 11% of them contained nitrosodiethylamine. Mutagenicity assays were performed in Salmonella typhimurium . Strains TA 98 and TA 100 were used in absence and presence of S9 mix. A dose-response curve of the mutagenic activity was observed in TA 100 with S9 mix. Unscheduled DNA synthesis assay also confirmed that the purified extracts of hams and sausages at doses as low as 1 ppb are inducers of damage to DNA of human foetal lung cells. 相似文献
10.
Nitrate, nitrite, and N-nitroso compounds in Finnish foods and the estimation of the dietary intakes
Pirjo -Liisa Penttilä Leena Räsänen Sinikka Kimppa 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1990,190(4):336-340
Summary An estimate of the dietary intakes of nitrite, nitrate andN-nitroso compounds is presented, based on the analytical data supplied by the Finnish Food Quality Control. Figures on the food consumption of the Finnish population, taken from a national dietary survey, and food consumption of 1768 children and adolescents over a 48-h recall period were used. The mean daily dietary nitrate intakes were estimated to be about 55 mg for the total population and for children and adolescents. The mean nitrite intakes were 1.88 mg for the total population and 1.07 mg for children and adolescents. The intake ofN-nitroso compounds (NDMA) was estimated to be 0.08 g for the total population and 0.02 g for children. Nitrates were found to originate mainly from vegetables (80%), nitrites from meat products (97%) and nitrosamines mostly from fish products and beer. A comparison of the estimate of dietary intake of nitrite with ADI values indicated that the nitrite intake of the total population was 23% and by children 39% of ADI. The average weight was approximately 60 kg for adults and 20 kg for children. When measured average weight (39 kg) was used, and the nitrite intake was found to be 28% of ADI. Nitrate intakes from food additives were 2.5% and 1.4% of the ADI value, respectively. When the total nitrate intake from various food sources was compared with the ADI (which is given only for food additives), the estimated nitrate intake of the total population was 25% and that of children 28% of the ADI value.
Nitrat, Nitrit und N-nitroso-Verbindungen in der finnischen Nahrung
Zusammenfassung Die Einnahme von Nitrat, Nitrit undN-Nitroso-Verbindungen stützt sich auf die analytischen Werte der finnischen Lebensmittelkontrolle. Für die Schätzung der Nahrungsaufnahme der finnischen Bevölkerung benutzte man Resultate einer nationalen Nahrungsforschung und eines 48-Stunden-Befundes für 1768 Kinder und Jugendliche. Die durchschnittliche tägliche Einnahme von Nitrat schätzte man auf ungefähr 55 mg für die ganze Bevölkerung. Die durchschnittliche Einnahme von Nitrit betrug 1,88 mg für die ganze Bevölkerung und 1,07 mg für Kinder und Jugendliche. Die Einnahme vonN-Nitroso-Verbindungen (NDMA) schätzte man auf 0,08 g für die ganze Bevölkerung und 0,02 g für Kinder. Die hauptsächliche Nahrungsquelle der Nitrate war Gemüse (80%) und bei den Nitriten die Fleischwaren (97%). Nitrosamine stammten hauptsächlich aus Fischwaren und aus Bier. Als man die geschätzte Einnahme von Nitrit mit den ADI-Werten verglich, ergab sich, daß die Einnahme von Nitrit 23% (ganze Bevölkerung) und 39% (Kinder) des ADI-Wertes war. Als durchschnittliches Körpergewicht nahm man 60 kg für Erwachsene und 20 kg für Kinder an. Wenn man den Wert des gemessenen durchschnittlichen Körpergewichts (39 kg) für Kinder benutzte, war die Einnahme von Nitrit 28% des ADI-Wertes. Die Einnahme von Nitrat in Zusatzstoffen war 2,5% und entsprechend 1,4% des ADI-Wertes. Die Einnahme von Nitrat in der Nahrung schätzte man auf 25% (ganze Bevölkerung) und auf 28% (Kinder) des ADI-Wertes (gegeben nur für Nitrat als Zusatzstoffe).相似文献
11.
Nitrate, nitrite, and N-nitroso compounds in Finnish foods and the estimation of the dietary intakes
P L Penttil? L R?s?nen S Kimppa 《Zeitschrift für Lebensmittel-Untersuchung und -Forschung》1990,190(4):336-340
An estimate of the dietary intakes of nitrite, nitrate and N-nitroso compounds is presented, based on the analytical data supplied by the Finnish Food Quality Control. Figures on the food consumption of the Finnish population, taken from a national dietary survey, and food consumption of 1768 children and adolescents over a 48-h recall period were used. The mean daily dietary nitrate intakes were estimated to be about 55 mg for the total population and for children and adolescents. The mean nitrite intakes were 1.88 mg for the total population and 1.07 mg for children and adolescents. The intake of N-nitroso compounds (NDMA) was estimated to be 0.08 micrograms for the total population and 0.02 micrograms for children. Nitrates were found to originate mainly from vegetables (80%), nitrites from meat products (97%) and nitrosamines mostly from fish products and beer. A comparison of the estimate of dietary intake of with ADI values indicated that the nitrite intake of the total population was 23% and by children 39% of ADI. The average weight was approximately 60 kg for adults and 20 kg for children. When measured average weight (39 kg) was used, and the nitrite intake was found to be 28% of ADI. Nitrate intakes from food additives were 2.5% and 1.4% of the ADI value, respectively. When the total nitrate intake from various food sources was compared with the ADI (which is given only for food additives), the estimated nitrate intake of the total population was 25% and that of children 28% of the ADI value. 相似文献
12.
A R Tricker M J Perkins R C Massey C Bishop P E Key D J McWeeny 《Food Additives & Contaminants》1984,1(3):245-252
Procedures are described for the use of high-performance liquid chromatography and gas chromatography with a chemiluminescence detector in the analysis of N-nitrosoamino acids, N-nitrosothiazolidine-4-carboxylic acid, N-nitroso-oxazolidine-4-carboxylic acids and N-nitroso dipeptides N-terminal in N-nitrosoproline in cured meat products. The detection limit is around 5-10 micrograms/kg. Evidence is presented for the presence of all these species except the N-nitrosated dipeptides. 相似文献
13.
目的建立气相色谱-质谱联用法(gas chromatography-mass spectrometry,GC-MS)测定啤酒中N,N-二甲基亚硝胺的不确定度评定的方法。方法从测定方法分析不确定度来源,计算各不确定度分量,合成扩展不确定度。结果该检测方法线性良好,线性方程为Y=0.00557X-0.0974,相关系数r=0.9994,相对标准偏差为1.11%。啤酒样品中的N,N-二甲基亚硝胺测定结果平均值为10.9μg/m L,扩展不确定度为1.56μg/mL。结论提出的方法适用于啤酒中N,N-二甲基亚硝胺的不确定度评定。 相似文献
14.
A review of the literature published prior to July 1991 covers the occurrence and formation of non-volatile N-nitrosamines occurring in foods and beverages. The presence of identified volatile and non-volatile N-nitrosamines accounts for less than 10% of the total apparent N-nitrosamine concentration. N-Nitrosoproline and N-nitrosothiazolidine-4-carboxylic acid are the most commonly identified non-volatile N-nitrosamines in the diet. Non-volatile N-nitrosamines account for 12 of the 21 currently identified N-nitroso compounds in foods and beverages. 相似文献
15.
An attempt has been made to briefly review methods available for the determination of total N-nitroso compounds, N-nitrosamides, N-nitrosamino acids, and miscellaneous other nonvolatile N-nitroso compounds in foods and beverages, giving special emphasis to the progress made during the past five years. It appears that a wide variety of acceptable methods are available for N-nitrosamino acids and simple hydroxylated N-nitrosamines, but none of them has yet been adequately validated. Only limited progress has been made for the analysis of N-nitrosamides, N-nitroso sugar amino acids, and other N-nitroso compounds. Various mass spectrometric methods available for the determination and confirmation of these compounds are also discussed. 相似文献
16.
17.
食品中N-亚硝基化合物的危害性及预防措施 总被引:3,自引:0,他引:3
N-亚硝基化合物是一广谱致癌物,其前体物质广泛存在于环境中,人类与之接触十分频繁。近年来国内外对食管癌、胃癌、鼻咽癌、肝癌、宫颈癌及膀胱癌的研究表明,可能与N-亚硝基化合物有关。文章对食品中N-亚硝基化合物的化学性质、分类结构、毒理作用、食物来源、污染途径对人体的危害作用以及预防措施进行了详细综述,旨在引起人们的重视,养成良好的饮食习惯,合理搭配膳食结构,向着利于身心健康的方向发展。 相似文献
18.
Peter F. Swann 《Journal of the science of food and agriculture》1975,26(11):1761-1770
Nitrate is essentially non-toxic to mammals but it can be reduced to nitrite either in improperly stored food, in the rumen of cattle, in the gastrointestinal tract of the human infant, and by the microflora of the human mouth. The nitrite from these and other sources, including that purposely added to food, presents a toxic hazard both because of the direct toxicity of nitrite, and by the formation of carcinogenic N-nitroso compound by reaction with amino compounds. Administration of toxic amounts of nitrite induces methaemoglobinaemia. The nature of this disease, its importance in human medicine and the reason for the particular sensitivity of the infant, are briefly discussed. The carcinogenic properties of N-nitroso compounds are described. These compounds have been found in the environment and may be formed in the stomach from amines and nitrite. Our knowledge of the amount of N-nitroso compounds to which man is exposed, is continually increasing but with the lack of epidemiologic evidence, the assessment of the significance to man of these traces of N-nitroso compounds depends upon the interpretation of animal experiments and their extrapolation to man. This extrapolation would be more certain if there were a more clear understanding of the factors determining tissue selectivity by carcinogens and tissue sensitivity, and of the mechanism of cumulation of carcinogenic doses and of synergism between carcinogens. Recent experiments suggest that there may soon be a significant breakthrough in the understanding of this. These experiments are briefly discussed. 相似文献
19.
Maximilian Michel Sandro Cocuzza Martin Biendl Frank Peifer Sebastian Hans Yvonne Methner Friedrich Pehl Werner Back Fritz Jacob Mathias Hutzler 《Journal of the Institute of Brewing》2020,126(4):354-361
Beer spoiling lactic acid bacteria are a major reason for quality complaints in breweries around the world. Spoilage by a variety of these bacteria can result in haze, sediment, slime, off-flavours and acidity. As these bacteria occur frequently in the brewing environment, using certain hop products that inhibit the growth of these spoilers could be a solution to prevent problems. To investigate the impact of seven different hop compounds (α-acids, iso-α-acids, tetrahydro-iso-α-acids, rho-iso-α-acids, xanthohumol, iso-xanthohumol and humulinones) on the growth of six major beer spoilage bacteria (Lactobacillus brevis. L. backi, L. coryniformis, L. lindneri, L. buchneri, Pediococcus damnosous), two concentrations (10 and 25 mg/L) of each hop substance were added to unhopped beer. The potential growth of the spoilage bacteria was investigated over 56 consecutive days. A comparison of the results shows a strong inhibition of growth of all spoilage bacteria at 25 mg/L of tetrahydro-iso-α-acids closely followed by α-acids as the second most inhibitory substance. The results showed a high resistance of L. brevis to all hop compounds as well as an inhibition of L. coryniformis and L. buchneri at low concentrations of most hop components. In comparison with the control sample, L. lindneri showed increased growth in the presence of some hop compounds (rho-iso-α-acids, xanthohumol, iso-xanthohumol, humulinones). © 2020 The Authors. Journal of the Institute of Brewing published by John Wiley & Sons Ltd on behalf of The Institute of Brewing & Distilling 相似文献
20.
分析了酿造后期至包装阶段、总氧及其组成在各环节的变化情况,指出了灌装过程总氧含量增加幅度最大的环节,并对灌装过程影响总氧的因素进行了探讨。 相似文献