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Iratxe Perez-Arnedo María J. Cantalejo Alba Martínez-Laorden Elena Gonzalez-Fandos 《International Journal of Food Science & Technology》2021,56(4):1855-1864
Microbiological contamination of chicken meat depends on the conditions under which the animals are reared, slaughtered and processed. The aim of this study was to determine the influence of farm origin and processing stages at slaughterhouse on the microbial safety and quality of chicken. Samples of chicken carcasses from three different farms were taken from a slaughterhouse. Mesophiles, Escherichia coli, coagulase positive Staphylococcci counts, presence of Listeria monocytogenes,Campylobacter and Salmonella were determined at five sampling points: after defeathering, after evisceration, after washing, after chilling and after cutting. Chilling reduced log numbers of mesophiles, coagulase positive Staphylococci and E. coli by 0.85, 1.52 and 2.2 log units, respectively. Salmonella was not detected after chilling. High prevalence of Campylobacter spp was observed at all the stages ranging between 84% and 100%. L. monocytogenes was not detected in chicken carcasses after defeathering. However, it was detected after evisceration and after washing and chilling. The most critical stage for L. monocytogenes contamination was the portioning operation, the prevalence in breast and legs being 88% and 84%, respectively. 相似文献
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A hybrid fluidized-bed bioreactor for water purification was proposed and analyzed. It is a novel type of bioreactor characterized by hitherto unknown stationary and dynamic features. Steady-state characteristics of this hybrid bioreactor with external liquid circulation are presented. A quantitative analysis of steady-state properties of the bioreactor was performed with the aid of an original mathematical model developed for a double-substrate aerobic microbiological process. A steady-state analysis of aerobic processes characterized by different oxygen demand was performed. The effect of essential parameters was evaluated, including carbonaceous substrate concentration in the feed stream to the apparatus, aeration intensity, total residence time of a liquid in the bioreactor, and height of the bed of fine carrier particles. 相似文献
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Foodborne illnesses are syndromes including nausea, vomiting, abdominal cramps and diarrhea caused by the ingestion of food contaminated by chemical substances or microorganisms and/or their toxins. Reporting of food poisoning has been mandatory for European Union member states since 2003. Data collected by the European Food Safety Authority (EFSA) include number of outbreaks per causative agent, number of human cases as well as hospitalization and death rates. This paper will focus on meat products as food vehicles for FBOs. Following the legal definition of meat and meat products and the European reporting scheme, the main pathogenic bacteria will be presented. 相似文献
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随着三元复合驱采油技术在油田的广泛应用,三元复合驱采出水产量不断增加。三元复合驱采出水水质复杂,具有矿化度高、黏度大、含油乳化程度高、小油滴含量高、油水分离困难等特点,对油田生产和环境的影响日益严重。因此,开展三元复合驱采出水高效处理方法的研究成为一项重要的任务。本文分析了影响三元复合驱采出水油水分离特性的各种因素,介绍了目前国内应用于三元采出水处理的先进技术,如膜分离法、气浮选分离法、高级氧化法、微生物法等,阐述了这些处理技术的优势及存在的问题,重点介绍了气浮选分离法和微生物法在三元采出水处理中的应用情况,并对大庆油田三元复合驱采出水现场处理工艺进行了介绍,最后对今后的研究工作提出了一些展望。 相似文献
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Assessment of chemical and microbiological parameters of indoor swimming pool atmosphere using multiple comparisons 下载免费PDF全文
The aim of this study was to evaluate the air quality of an indoor swimming pool, analyzing diurnal and seasonal variations in microbiological counts and chemical parameters. The results indicated that yeast and bacteria counts, as well as carbon dioxide (CO2), nitrogen oxides (NOx) and O3 concentrations, showed significant diurnal difference. On the other hand, temperature, relative humidity (R.H.), yeast counts and concentrations of CO2, particles, O3, toluene, and benzene showed seasonal differences. In addition, the relationship between indoor and outdoor air and the degree of correlation between the different parameters have been calculated, suggesting that CO2, fine particles and NOx would have indoor origin due to the human activity and secondary reactions favored by the chemical and environmental conditions of the swimming pool; while O3, benzene and toluene, would come from outside, mainly. The overall results indicated that indoor air quality (IAQ) in the swimming pool building was deficient by the high levels of CO2 and microorganisms, low temperatures, and high R.H., because frequently the limits established by the legislation were exceeded. This fact could be due to the poor ventilation and the inadequate operation of heating, ventilation, and air‐conditioning systems. 相似文献
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从后期质量跟踪的角度,对自主招生学生进校后的情况进行了跟踪调研,通过学生问卷调查结合大量的客观数据统计,从能力素质方面及学习成绩、奖学金获得、参加科研情况等多角度分析、比较自主招生和普通高考两类学生入校后的差异,并在此基础上分析结论背后的原因,以此检验CQ大学自主招生效果,回答社会对自主招生的质疑,丰富相关研究领域成果。研究表明,自主招生学生能力素质均分及各项能力素质均显著高于普通高考学生;自主招生学生成绩略高于普通高考学生;自主招生学生综合素质表现(综合奖学金、五四评优、争先创优)显著高于普通高考学生;自2015年开始自主招生学生科创能力(科创项目立项)显著高于普通高考学生。 相似文献
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本文总结论述了我国迅速发展的平板网架结构,并详细对结构的形式、连接方法、计算分析、施工与质裣、以及屋面材料、支座形式和防火、防锈涂料等方面发展状况进行了评述,最后还列示了有代表性的几十个典型工程实例。 相似文献
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