Monte Carlo simulations assessing the risk of salmonellosis from consumption of almonds

Recent outbreaks of salmonellosis associated with raw almonds have raised awareness of this food as a vector for foodborne illness. We performed a quantitative assessment of the risk of contracting salmonellosis from consumption of raw almonds, accounting for factors that become important after almonds reach the processor. We estimated the risk associated with the consumption of raw almonds and the risk reduction associated with almonds treated with a theoretical 5-log reduction process or treated with propylene oxide using a standard commercial process. Probability distributions were chosen to describe the chance of almond contamination and the effects of storage time, storage temperature, and processing from currently available data. A beta-Poisson model for the dose-response relationship for Salmonella was obtained from published literature. The simulation estimated a 78% chance of one or more cases of salmonellosis per year from consumption of raw almonds. The application of a commercial propylene oxide treatment reduced this risk to 0.01%. Hypothetical 5-log reduction treatments with different standard deviations (+/-1, +/-0.5, +/-0.1, and +/-0) reduced the predicted yearly risk of salmonellosis to 0.69, 0.35, 0.30, and 0.21%, respectively. These results suggest that the risk of one or more U.S. cases of salmonellosis per year from consumption of raw almonds can be reduced from 78% to less than 1% by using a process achieving a 5-log reduction in Salmonella with a process standard deviation as large as 1 log unit or by using a commercial propylene oxide treatment.     

DNA barcoding detects market substitution in North American seafood

Seafood authentication and food safety concerns are a growing issue in today’s global marketplace, although traditional morphology-based identification keys and existing molecular approaches have limitations for species identification. Recently, DNA barcoding has gained support as a rapid, cost-effective and broadly applicable molecular diagnostic technique for this purpose. However, the maturity of the barcode database as a tool for seafood authentication has yet to be tested using real market samples. The present case study was undertaken for this reason. Though the database is undergoing continual development, it was able to provide species matches of >97% sequence similarity for 90 of 91 samples tested. Twenty-five percent of the samples were potentially mislabeled, demonstrating that DNA barcodes are already a powerful tool for the identification of seafood to the species level. We conclude that barcodes have broad applicability for authenticity testing and the phylogeographic patterning of genetic diversity can also inform aspects of traceability.     

Quantitative risk assessment of human salmonellosis from the consumption of a turkey product in collective catering establishments

The quantitative risk assessment (QRA) approach recommended by the Codex Alimentarius Commission was used to assess the risk of human salmonellosis from the consumption of 'cordon bleu', a specific turkey product, in collective catering establishments (CCEs) of a French department. The complete process was modeled and simulated, from the initial storage in the CCE freezer to the consumption, using a Monte Carlo simulation software. Data concerning the prevalence of contaminated 'cordon bleu', the level of contamination of Salmonella, the cooking and storage process were collected from 21 CCEs and 8 retailers of 'cordon bleu' in the selected department. Thermal inactivation kinetics for Salmonella were established to estimate the effect of heat treatment on the concentration in the product and to calculate the dose that could be ingested by the consumer. The Beta-Poisson dose-response model of Rose and Gerba [Water Science and Technology 24 (1991) 29] with the specific parameters for Salmonella was used to estimate the probability of infection related to the ingestion of a particular dose and a factor was applied to estimate the probability of illness from ingestion. The individual risk of salmonellosis, the risk of outbreak and the number of cases were calculated using Monte Carlo simulation method. The risk of salmonellosis was close to zero when the 'cordons bleus' were cooked in the oven. Therefore, the risk was calculated for the fryer cooking since the insufficient cooking time observed was, sometimes, at the origin of low temperatures (37-89 degrees C). The influence of both the initial concentration of Salmonella in the product and the heat storage before consumption on the final risk was studied. For a high initial concentration of Salmonella in the product, when the 'cordons bleus' are fryer cooked, the average risk of salmonellosis was equal to 3.95 x 10(-3) without storage before consumption and 2.8 x 10(-4) if the product is consumed after storage. This paper presents the results of the QRA and discusses risk management options to minimize the risk of salmonellosis.     

日本葡萄酒消费市场

日本葡萄酒消费市场,近几年总量与中国接近,每年葡萄酒消费量近30万吨,但中、日两国葡萄酒市场消费特点却有着明显的差异:日本为经济发达国家,葡萄酒消费总的趋势是向中、高档酒方向发展,中国是发展中国家,消费的葡萄酒大多是中、低档酒;日本市场上的国产、进口葡萄酒比例已达到4:6,即六成为进口酒,中国葡萄酒市场上大部分为国产酒,进口葡萄酒仅占一成多;还有,两国都属东亚国家,不如法国、意大利、葡萄牙、瑞士、西班牙、德国、澳大利亚、智利等国家,葡萄酒人均年消费量都在几十升,但日本1998年起人均年消费量也已达2L以上(见表1),而中国目前还不到0.3L.     

An international outbreak of salmonellosis associated with raw almonds contaminated with a rare phage type of Salmonella enteritidis

During the winter of 2000 to 2001, an outbreak due to Salmonella Enteritidis (SE) phage type 30 (PT30), a rare strain, was detected in Canada. The ensuing investigation involved Canadian and American public health and food regulatory agencies and an academic research laboratory. Enhanced laboratory surveillance, including phage typing and pulsed-field gel electrophoresis, was used to identify cases. Case questionnaires were administered to collect information about food and environmental exposures. A case-control study with 16 matched case-control pairs was conducted to test the hypothesis of an association between raw whole almond consumption and infection. Almond samples were collected from case homes, retail outlets, and the implicated processor, and environmental samples were collected from processing equipment and associated farms for microbiological testing. One hundred sixty-eight laboratory-confirmed cases of SE PT30 infection (157 in Canada, 11 in the United States) were identified between October 2000 and July 2001. The case-control study identified raw whole almonds as the source of infection (odds ration, 21.1; 95% confidence interval, 3.6 to infinity). SE PT30 was detected in raw whole natural almonds collected from home, retail, distribution, and warehouse sources and from environmental swabs of processing equipment and associated farmers' orchards. The frequent and prolonged recovery of this specific organism from a large agricultural area was an unexpected finding and may indicate significant diffuse contamination on these farms. Identification of almonds as the source of a foodborne outbreak is a previously undocumented finding, leading to a North American recall of this product and a review of current industry practices.     

Hexachlorocyclohexanes in the North American atmosphere

Annually integrated air concentrations of alpha- and gamma-hexachlorocyclohexane (HCH) were determined in 2000/2001 at 40 stations across North America using XAD-based passive air samplers to understand atmospheric distribution processes on a continental scale. Elevated levels of gamma-HCH in the atmosphere of the Canadian Prairies are consistent with the ongoing use of lindane as a seed treatment on canola and confirm the feasibility of detecting the agricultural use of a pesticide using long-term integrated passive air sampling. In contrast to gamma-HCH, the atmospheric concentrations of alpha-HCH show a rather uniform distribution across Canada and the United States, which is expected for a chemical with no current use on the continent. Higher levels in the atmosphere over Atlantic Canada can be explained by alpha-HCH evaporating from the waters of the Labrador Current, which is supported bythe chiral composition of alpha-HCH and the temperature dependence of its atmospheric concentrations along the east coast of Canada. Similarly, alpha-HCH is volatilizing from Lake Superior. Atmospheric HCH levels increase with elevation in the Canadian Rocky Mountains. The results suggest that evaporation, in particular from cold water bodies, is an important source of alpha-HCH to the North American atmosphere. Low levels of HCHs in Central America hint at efficient degradation under tropical conditions. Chiral analysis shows that (+)-alpha-HCH is often enriched in air over continental areas and at the Pacific Coast, which is opposite to the enantiomeric enrichment in the proximity to the Great Lakes and the Atlantic Ocean. Passive air sampling is a powerful tool to discern the large-scale variability of semivolatile and persistent organic chemicals in the atmosphere.     

浅析我国液体牛奶市场消费状况

分析了2001年全国液体牛奶的市场状态和消费结构。在对液体牛奶的市场分析中，叙述了各知名品牌的市场占有率变化；消费者对最佳品牌的认同情况；市场集中度的变化趋势以及WTO对中国液体牛奶市场的影响等。在对液本牛奶的消费分析中，着重阐述了消费者的购买决策影响因素、购物场所的选择、消费频次、饮用类型、饮用时段、饮用场合、饮用目的等方面观点。     

Quantitative risk assessment for human salmonellosis through the consumption of pork sausage in Porto Alegre, Brazil

A quantitative microbiology risk assessment was conducted to evaluate the risk of Salmonella infection to consumers of fresh pork sausages prepared at barbecues in Porto Alegre, Brazil. For the analysis, a prevalence of 24.4% positive pork sausages with a level of contamination between 0.03 and 460 CFU g(-1) was assumed. Data related to frequency and habits of consumption were obtained by a questionnaire survey given to 424 people. A second-order Monte Carlo simulation separating the uncertain parameter of cooking time from the variable parameters was run. Of the people interviewed, 87.5% consumed pork sausage, and 85.4% ate it at barbecues. The average risk of salmonellosis per barbecue at a minimum cooking time of 15.6 min (worst-case scenario) was 6.24 × 10(-4), and the risk assessed per month was 1.61 × 10(-3). Cooking for 19 min would fully inactivate Salmonella in 99.9% of the cases. At this cooking time, the sausage reached a mean internal temperature of 75.7°C. The results of the quantitative microbiology risk assessment revealed that the consumption of fresh pork sausage is safe when cooking time is approximately 19 min, whereas undercooked pork sausage may represent a nonnegligible health risk for consumers.     

Phylogenetic identification of Aeromonas from pigs slaughtered for consumption in slaughterhouses at the North of Portugal

In the present study, 710 isolates of Aeromonas spp. have been collected from pig carcasses, diaphragm muscle, faeces, dehairing equipment and water in slaughterhouses at the North of Portugal. The isolates were obtained from a total of 154 samples. All presumptive Aeromonas isolates were subjected to ERIC-PCR analysis and those which presented a different pattern were taken and the species classified by gyrB gene sequencing. We have found the species A. hydrophila, A. salmonicida, A. bestiarum, A. caviae, A. media, A. veronii, A. allosaccharophila, A. simiae and A. aquariorum. To our knowledge, this extent of Aeromonas species diversity has not been previously described from meat or from the slaughter environment, perhaps due to the unreliability of available identification methods. A noticeable level of isolate redundancy (strains with identical gyrB sequence) from different samples collected in different dates was also obtained, indicating that only a few predominant strains of these species persist at the slaughter system. It is also important to emphasise the presence of Aeromonas species previously associated with illness in man.     

Contributor factors for the occurrence of salmonellosis during preparation,storage and consumption of homemade mayonnaise salad

This study aimed to analyze the impact of practices adopted for preparation, storage and consumption of homemade mayonnaise salad (HMS) as contributor factors for the occurrence of salmonellosis. A total of 493 individuals answered a questionnaire composed of demographic and socioeconomic questions and, preparing, storage and consumption practices of HMS. The level of good hygiene practices (GHP) of respondents was calculated using Good Practice and Outbreak Prevention Indexes. The consumer behavior and the correlation between practices were performed using Multiple Correspondence Analysis (MCA). 75% of respondents consume HMS, being 43% of interviewers doing this at least once per month. HMS was prepared from 30 min to 1 h before being served by 46% of individuals, it remaining for 30 min to 1 h at room temperature during the meal by 63% of people. Furthermore, 51% of respondents left the HMS container open or improperly closed, which may lead to cross-contamination. Most respondents (66%) stated reuse the HMS for less than one day (44%), at once (76%). 77% of participants declared that they prepare HMS, being only 7% preparing HMS without eggs. The majority (51%) used a cooked and a raw egg yolk. In addition, 75% of the cases showed raw eggs in recipe. The Weighted Good Practice Index, Weighted Outbreak Prevention Index and Weighted Harmonic Outbreak Prevention Index were 63%, 62% and 27% of participants, respectively. The MCA gathered the participants into two groups one commits various errors and other commits few errors on GHP. Thus, a consumer would probably perform multiple either good or bad practices simultaneously.     

源自生活形态的女装市场细分及其消费特征

针对女装市场从生活形态视角进行市场细分研究,以期为企业进行精准营销提供参考。以杭州女装消费群为研究对象进行问卷调查,通过因子、聚类分析,划分出享受奋斗型、居家时尚型、理性自信型和随意现实型4个消费者细分市场。然后通过对人口统计因素和消费行为因素进行卡方检验,研究不同消费群类在年龄、职业、消费行为、购买意愿上存在显著差异。最后对各消费群类与人口因素及消费行为间的联系进行了对应分析,从而勾勒出杭州女装市场各消费群类的典型特征。     

2001美国最佳乳品

创新可以赋予产品更多的激情,并影响着市场的推广与发展,它也是使商家成为赢家的一个重要因素。     

近年和未来两年北美板材产量情况

住宅建设、维修以及家具业等相关行业对北美板材市场的繁荣至关重 要.伴随房地产市场处于历史性低谷、家具产业下滑,2008-2009年北美板材的消费及生产也呈现下滑趋势. 基于GDP和目前住房消费指数,表1总结了最近2年的数据,提供了北美地区2008年产量的估计数据,预测了2009-2011年的数据.     

无锡小排骨

由于饮茶的人群数量呈现上升之势,茶吧已经开始遍布美国,但咖啡在美国市场仍然保持霸主地位.     

南京地区乳品消费市场调查分析

通过调查问卷与走访方式对"三鹿牌婴幼儿奶粉事件"前后南京地区乳品消费品牌信任状况、乳品消费倾向情况和乳品消费量变化情况的调查,以期为我国轧品行业的发展提出科学的导向性的建议意见和发展思路.结果表明:"三鹿牌婴幼儿奶粉事件"发生后,经过一年的恢复期,我国乳品行业已基本走出事件后所造成的行业低谷期.目前,无论是乳制品的消费量,还是消费者对乳品企业及行业的信任状况较之前都有着大幅的提升.     

大扁杏杏仁油的脂肪酸分析

采用索氏提取法对大扁杏杏仁中油脂进行提取,并将油脂用饱和氢氧化钾-甲醇皂化,再用甲醇-硫酸(体积比为4∶1)甲酯化后,将乙醚萃取液作气相色谱-质谱联用仪分析。结果表明,大扁杏杏仁的出油率为51.2%,脂肪酸组分主要为油酸(77.08%),亚油酸(6.12%),棕榈酸(7.12%),亚麻酸(3.44%),硬脂酸(1.36%)等,其中不饱和脂肪酸占86.64%。     

重庆地区中学校校服消费市场调查分析

通过对重庆3个中学600名中学生和学生家长的问卷调查,对目前重庆地区校服的款式特征、认同感、满意度、着穿校服地原因等情况进行了分析,并对重庆地区中学校服的设计提出了建议。     

Polyfluorinated telomer alcohols and sulfonamides in the North American troposphere

In 2001, a sampling campaign was conducted in six North American cities--Reno, NV; Griffin, GA; Cleves, OH; Winnipeg, MB; Long Point, ON; and Toronto, ON--to investigate the tropospheric distribution of a suite of polyfluorinated alcohols and amides. Analysis via gas chromatography-chemical ionization-mass spectrometry indicated that both polyfluorinated sulfonamides and fluorinated telomer alcohols (FTOHs) are widely distributed throughout the North American troposphere with mean concentrations ranging from 22 to 403 pg/m3 and from 11 to 165 pg/m3 respectively. The dominant polyfluorinated contaminant was dependent on sampling location. Large mean concentrations of N-methyl perfluorooctane sulfonamidoethanol (359 pg/m3) and N-ethyl perfluorooctane sulfonamidoethanol (199 pg/m3) identified in Griffin and Reno, respectively, may indicate the release of polyfluorinated sulfonamides to the environment through paper and carpet treatment processes. The nonuniform nature of the spatial distribution of both polyfluorinated sulfonamides and FTOHs is indicative of the importance of point sources for the dissemination of these contaminants in the North American troposphere.     

Poly and perfluorinated carboxylates in North American precipitation

Although perfluorocarboxylates (PFCAs) have been detected in a number of environmental matrices, there are very few reports on concentrations in precipitation. In this study PFCAs, fluorotelomercarboxylates (FTCAs), and fluorotelomer-unsaturated carboxylates (FTUCAs), were determined in wet only precipitation samples from nine sites in North America. The analytical method involved derivatization of the carboxylates and measurement of the 2,4-difluoroanilide by GC-MS. Samples from three remote sites in Canada had low concentrations of perfluorooctanoate (PFOA) (<0.1-6.1 ng/L). Significantly higher concentrations of PFOA were found at 4 northeastern United States and 2 southern urban Canadian sites, with Delaware having the highest levels (85 ng/L PFOA, with a range of 0.6-89 ng/L) and a maximum flux of 13 000 ng/m2. 8:2- and 10:2 FTCAs and FTUCAs were detected at all 4 U.S. sites and 2 urban Canadian sites (<0.07-8.6 ng/L), most frequently at the Delaware site. Longer chained PFCAs (deca-, undeca-, and dodeca-perfluorocarboxylates) were detected (<0.07-5.2 ng/L) at 2 urban Ontario sites but not determined in other samples. Air mass back trajectory results for 3 U.S. sites indicate highly populated urban areas in the New York to Washington corridor as the main sources of PFOA, although low PFOA levels associated with air masses coming off the Atlantic Ocean imply multiple sources.     

合肥地区乳品消费市场调查分析

对合肥地区乳品市场品牌认同情况及消费者购买决策影响因素的调查，提出合肥乳品企业面对激烈竞争采取的应对措施和发展思路。