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2.
固相萃取-气相色谱-质谱分析肉样中盐酸克伦特罗的残留量 总被引:25,自引:12,他引:25
建立了固相萃取 气相色谱 质谱联机分析肉样中盐酸克伦特罗残留量的方法。对盐酸克伦特罗在C1 8和离子交换固相萃取柱上的保留行为进行了研究 ,发现不同浓度盐酸克伦特罗的固相萃取回收率在 75 %~ 95 %之间 ;肉样中的加标回收率在 70 %~ 83 % ;相对标准偏差在 4 .95 %~ 1 3 .4 % ;最低检出限为 1 μg kg。盐酸克伦特罗的硅烷化产物 ,采用选择离子的模式进行检测 ( 86、2 4 3、2 62、2 77) ,衍生物的峰面积与样品浓度在0 .0 0 2 5 2~ 2 .0 2mg L范围内呈良好的线性关系 ,线性回归系数大于 0 .9999。 相似文献
3.
Mnica S. Brito Anna Lúcia C. H. Villavicencio Jorge Mancini-filho 《Radiation Physics and Chemistry》2002,63(3-6):337-340
In order to give the consumer the assurance that meat processed by irradiation is a safe product, a great deal of research has been developed in the world. The effect of irradiation on the hygienic quality of meat and meat products is considered as related to the control of meat-borne parasites of humans; elimination of pathogens from fresh meat and poultry; and elimination of pathogens from processed meat. Lipid oxidation and associated changes are the major causes of the quality deterioration of meat during storage. Irradiation of lipids induces the production of free radicals, which react with oxygen, leading to the formation of carbonyls, responsible for alterations in food nutritional and sensorial characteristics. Trans fatty acids are present in ground beef and can also be formed during its processing. Interestingly, the trans fatty acids, due to their chemical and physical characteristics, show more resistance to the oxidizing process. This property motivated us to investigate the level of the trans fatty acids, as well as the level of oxidation in irradiated ground beef. Irradiation of ground beef was performed by gamma rays from a 60Co source. The applied radiation doses were 0; 1.0; 2.0; 3.0; 4.0; 5.0; 6.0; 7.0 and 8.0 kGy. Lipid peroxidation in terms of TBA number and carbonyl content was monitored during storage. The sample characteristics and trans fatty acids composition were measured, following irradiation and after 60 and 90 days of storage at –10°C. 相似文献
4.
Mahrour A. Lacroix M. Nketsa-Tabiri J. Calderon N. Gagnon M. 《Radiation Physics and Chemistry》1998,52(1-6):81-84
This study was undertaken to determine if a combined treatment (marinating in natural plant extracts or vacuum) with irradiation could have a synergetic effect, in order to reduce the dose required for complete elimination of Salmonella on fresh poultry. The effect of these combined treatments on the shelf-life extension was also evaluated. The fresh chicken legs were irradiated at 0, 3 and 5 kGy. The poultry underwent microbial analysis(mesophilic and Salmonella detection). For each treatment, the total microbial count decreased with increase of irradiation dose. The marinating treatment have a synergistic effect with irradiation treatment to reduce the total microbial count and controlling the proliferation during storage at 4°C. Irradiation of fresh chicken pieces with a dose of 3 kGy appears to be able to extend the microbial shelf-life by a factor of 2. When the chicken is marinating and irradiated at 3 kGy or when irradiated at 5 kGy without marinating, the microbial shelf-life is extended by a factor of 7 to 8. No Salmonella was found during all the experiment in the chicken in air and marinated. However, a presence of Salmonella was found in samples irradiated at 5 kGy under vacuum, in unirradiated samples and samples irradiated at 3kGy in air and under vacuum. 相似文献
5.
Many countries allow the treatment of foods with low doses of ionizing radiation to reduce microbial and insect infestations, inhibit maturation, and extend shelf life. Therefore, a reliable method is needed to identify irradiated foods and to determine their compliance with respect to allowable absorbed radiation dose. Several approaches for the identification of irradiated foods have been developed such as measurement of radiolytic products, chemiluminescence, and thermoluminescence, and the use of electron spin resonance spectroscopy to measure free radicals trapped in bone. A method for the determination of radiolytically produced hydrocarbons was developed in our laboratory to evaluate the utility of monitoring these compounds as indicators of food irradiation. The method involves the extraction of the radiolytic hydrocarbons from foods and their quantitation by gas chromatography. Concentrations of the radiolytically produced hydrocarbons increased linearly with radiation doses ranging from 0 to 6 kGy. The limit of detection appears to be approximately 1 kGy. The method was found to be useful for the identification of gamma-irradiated foods such as shrimp, frog legs, pork, beef, and poultry. Results of the method evaluation studies of these food matrices as well as factors affecting hydrocarbon production and determination will be presented. 相似文献
6.
Chirag Patel Vishwanada Sastry Datta Madamwar 《Applied biochemistry and biotechnology》1996,56(1):89-94
To obtain enriched methane content and improve the anaerobic digestion of a mixture of cattle dung, poultry waste, and cheese
whey, the effect of various doses of Tegoprens: T-3012, T-3022, T-5842, T-5843, T-5851, T-5852 has been studied, in bench-scale
digesters. Among them, Tegoprens 3022 showed more than a 45% increase in gas production with higher methane content. 相似文献
7.
《Arabian Journal of Chemistry》2022,15(10):104116
The misuses of veterinary drugs can result in the accumulation of residues in food of animal origin that can make its way to the final consumer. Herein we describe a simple method for the accurate determination of beta-lactams, quinolones, sulphonamides, and tetracyclines in fish, poultry, and red meat. No extraction cartridges were used; instead, the extraction process consisted of the addition of an organic solvents, shaking, centrifugation, and dilution. An extensive validation process demonstrated an excellent linearity (R2 ≥ 0.99) for 23-drug residues. The recovery of drugs in different matrices at two concentration levels (n = 6) was in the range of 82–119%. The method was proved to be repeatable and reproducible with intra/inter-day measurements (RSDs lower than 20%). The quantification limits of drug residues were in the range of 0.8 to 45.3 ug/kg, which is well below the maximum residue limits set by most regulatory authorities. This method was successfully applied to the routine analysis of 20 fish, poultry, and red meat samples (n = 60). 相似文献
8.
Amol D. RautRavindranath Shashidhar Jayant R. Bandekar Balu P. Kapadnis 《Radiation Physics and Chemistry》2012,81(1):82-85
Campylobacter, a common poultry intestine commensal, is a well known cause of human gastric illnesses across the globe. Consumption of contaminated poultry meat is a major cause of Campylobacter related infections. In the present study, radiation sensitivity of indigenous strains of C. jejuni and C. coli isolated from poultry was evaluated. The decimal reduction dose (D10) values of different Campylobacter isolates at 0-4 °C in saline and blood broth were in the range of 0.120-0.210 kGy and 0.170-0.234 kGy, respectively. D10 values in chicken meat homogenate for Campylobacter were in the range of 0.110-0.190 kGy. Chicken meat samples were inoculated with C. jejuni and exposed to gamma radiation to study the effectiveness of radiation treatment in elimination of Campylobacter. Radiation treatment with a dose of 1 kGy could achieve complete elimination of 105 CFU of Campylobacter/g in poultry meat samples. No recovery of Campylobacter was observed, even after enrichment and selective plating in 1 kGy treated chicken meat samples stored at 4 °C up to 7 days. Present study shows that irradiation of poultry meat with 1 kGy can ensure safety of poultry meat. 相似文献
9.
10.
An ‘on-water’, efficient, high yielding, expeditious method has been developed for the synthesis of 1,4-dihydropyridine (1,4-DHP) derivatives via an one-pot multi-component condensation of dimedone or 4-hydroxycoumarine, aldehydes, and ammonium acetate using Fe3O4@SiO2 nanoparticles as a recyclable heterogeneous catalyst. This method takes advantage of the fact that water, a green solvent is used in combination with Fe3O4@SiO2 nanoparticles as catalyst which can be easily recovered magnetically and reused for further runs. 相似文献