Abstract:Objective VITEK matrix-assisted laster desorption ionization-time of flight mass spectrometry (VITEK MALDI-TOF MS,hereinafter referred to as VITEK MS). To study the impact of different sample preparation procedures for Cronobacter sakazakii identification and its traceability. And two data acquisition softwares of VITEK MS and MALDI 7090 were used to compare the differences of mass spectrograms between them. Methods Twenty two strains, including 18 isolated Cronobacter sakazakii strains, two Cronobacter sakazakii reference strains, one Enterobacter cloacae reference strain and one Citrobacter freundii reference strain were prepared respectively by three different preparation procedures, including direct transfer method, formic acid extraction method and formic acid-acetonitrile extraction method, and analyzed by MS. A detailed analysis of mass spectrograms was obtained from the software of VITEK MS. The result were compared with biochemical result. Then, the impact of sample preparation method on the identification result was evaluated by researching the consistency of result derived from three different preparation method, The traceability of 20 Cronobacter sakazakii strains was also investigated by the cluster analysis of VITEK MS result. The same strains were analyzed by MALDI 7090, and the mass spectrograms were compared with those by VITEK MS. Results The 20 strains were identified by VITEK MS as Cronobacter sakazakii, which were in consistent with biochemical result and could be distinguished from Enterobacter cloacae and Citrobacter freundii. There was no significant difference in the result confidence among the three different preparation procedures(P>0.05), but the number of mass peaks and their relative intensities showed remarkable difference. The formic acid extraction method achieved spectra consisting of >15 peaks and mass ranges of 2 000-15 000 m/z, of which relative intensities were >5 mV. At similarity level of 80%, the 20 strains prepared by the formic acid extraction method were classified into 5 clusters by the cluster analysis of VITEK MS result, through which the transmission route of Cronobacter sakazakii could be identified. There was no obvious difference in the peak positions and relative intensity between VITEK MS and MALDI 7090. Conclusion MALDI-TOF MS was considered as a reliable technique in the identification of Cronobacter sakazakii. The formic acid extraction method was more suitable for the identification of Cronobacter sakazakii by MALDI-TOF MS, which will be a useful technique for Cronobacter sakazakii trace. There was no obvious difference in the mass spectrograms between VITEK MS and MALDI 7090.

Abstract:Objective To find out the serotype distribution, molecular subtyping and drug resistance patterns of Salmonella isolates from marketed meat products in Shanghai. Methods A sentinel supermarket or market near an intensive community from each of 16 administrative regions in Shanghai were randomly selected, in which livestock and poultry meat products were collected regularly from January to August in 2016. Salmonella isolation and serotyping, antibiotic susceptibility testing, as well as molecular subtyping were conducted according to the foodborne disease surveillance monitoring program of the China National Center for Food Safety Risk Assessment. Results A total of 158 Salmonella strains were isolated from 606 commercially available meat products including pork, chicken, duck, beef, mutton and goose. Total positive rate was 26.1%(158/606), separation rates for livestock and poultry were 52.5%(83/158) and 47.5%(75/158) respectively. Salmonella enteritis, Salmonella typhimurium, Salmonella derby, Salmonella rissen and Salmonella indiana were the top 5 Salmonella serovars for meat products in Shanghai, but serovar type distributions in livestock and poultry were significantly different (P<0.05). Sulfisoxazole had the highest drug resistance rate for 158 Salmonella strains(79.7%,126/158), followed by streptomycin, nalidixic acid, ampicillin, tetracycline and chloramphenicol (38.0%～77.8%). Moreover, 123 strains (77.8%) were multi-drug resistant (MDR) strains. Drug resistance rates of gentamicin, streptomycin, sulfonamides, trimethoprim/sulfamethoxazole, chloramphenicol, tetracycline and ceftiofur, ceftriaxone and nalidixic acid were significant different in Salmonella strains from pigs and chicken(P<0.05). Six antibiotics exceeded the detection limits in almost half of the Salmonella strains. Salmonella enteritis strains had 15 PFGE patterns, in which type 1 and type 3 were predominant clones. Salmonella typhimurium strains had 23 significant different PFGE patterns, which showed genetic polymorphism features. Conclusion Salmonella contamination in retail meat and poultry is the main reason which leads to high Salmonella positive rate in Shanghai, the multidrug-resistant of Salmonella in meat products is serious and must be paid attention to. Salmonella rissen from pigs and Salmonella give from chicken are the newly imported animal originated Salmonella serovars.

Abstract:Objective To describe the burden of disease in Hunan Province caused by mushroom poisoning, and provide evidence basis for the management of heath resources. Methods Throughout 2016, in Hunan Province, questionnaire survey for burden of disease involving mushroom poisoning patients was conducted along with field investigations. Results Two hundred and thirty-two individuals who went to hospital after consuming poisonous mushrooms in 2016 were surveyed, and the financial cost added up to ￥998 889 (￥4 306 on average), consisting of ￥959 658 of direct financial burden and ￥39 231of indirect financial burden. Conclusion The financial burden of disease for poisonous mushrooms in Hunan Province in 2016 was ￥4 306 on average. It was estimated that for 1 632 cases recorded by the provincial foodborne disease surveillance system in 2016, the total financial burden of disease was ￥7 027 392.

Abstract:Objective To understand the distribution characteristics of serogroups and the heat resistant direct hemolysin (TDH) and TDH related hemolysin (TRH) of Vibrio parahaemolyticus strains from different sources in Pingyang County, Wenzhou City. Methods Fifty-nine food isolates and 39 clinical isolates of Vibrio parahaemolyticus were selected as the research objects. Serological grouping was performed with standard serum. Real-time polymerase chain reaction (PCR) was used to detect tdh gene and trh gene. Results There were 9 serogroups in the food isolates with no dominant serogroup. O1, O3 and O4 were detected in the clinical isolates, with O3 and O4 accounting for 48.7%(19/39) and 46.2%(18/39) respectively. The detection of virulence genes of isolates from foodborne diseases showed that 38 strains contained only tdh gene and 1 strain contained only trh gene. There was only one strain contained tdh gene detected from the food isolates. Conclusion There were differences of the major serotypes and the virulence genes between Vibrio parahaemolyticus strains isolated from the food and hospital in Pingyang County. This work provided a scientific basis for the prevention and rapid test of foodborne diseases caused by Vibrio parahaemolyticus.

Abstract:Objective The method of rapid detection of main ingredients in infant formula milk powder was studied by near infrared spectroscopy. Methods A total of 100 samples of 12 brands of infant formula were collected, and 10 000-4 000 cm-1 band of near-infrared spectra were collected. The calibration model was established by principal component regression and partial least square method. Results The model predicted the best result by partial least-squares method and standard normal variable transformation pretreatment. The predicted variances of main ingredients, protein, fat, dietary fiber, moisture, ash, carbohydrate and energy were 98.44%, 97.40%, 96.18%, 96.74%, 96.97%, 96.55% and 95.35%, and the estimated standard error were 0.354 2,0.473 8,0.201 4,0.105 8,0.093 61,0.520 7 and 13.64. For external validation of the model, the predictive value of 7 main ingredients of the predicted sample was compared with that of the laboratory test result. Comparison result of relative error and relative deviation were below 5.00%. The result of seven main ingredients met the precision requirements of national standards. Conclusion The method could be used to determine the quantity fraction and quantity of protein, fat, dietary fiber, moisture, ash, carbohydrate and energy in infant formula and the quality.

Abstract:Objective To establish a method for the simultaneous determination of ofloxacin, norfloxacin, ciprofloxacin, pefloxacin, danofloxacin, lomefloxacin, enrofloxacin, ciprofloxacin, pefloxacin, oxolinic acid and flumequine,tetracycline, chlortetracycline, oxytetracycline and doxycycline in animal tissue by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) with automatic solid phase extraction. Methods The samples were extracted with 0.1 mol/L EDTA-Mcllcaine buffer solution (pH=4.0), and the resulting extracts were cleaned-up on HLB solid phase extraction column, and then eluted with 100% methanol. The target components were separated on a UPLC C₁₈ column (100 mm×2.1 mm, 1.6 μm), with 0.1% formic acid water and methanol-acetonitrile (40∶60, V/V) solution as mobile phase in gradient elution. Multiple reaction monitoring (MRM) in positive was used, qualitative confirmation was performed from retention time and secondary mass characteristic ions, and the matrix-matched external standard calibration curves were used for quantitative analysis. Results The target components and impurity could be well separated, it was showed good linearity in the range of 1.25-50.0 μg/kg (r=0.998 5 above). The detection limits and quantitation limits of 11 kinds of quinolones were 0.013-0.069 and 0.043-0.23 μg/kg, the limits of 4 kinds of tetracyclines were 0.033-0.093 and 0.11-0.31 μg/kg. The recovery tests at high, medium, and low spiked levels:the recoveries were 70.8%-105.4%, and relative standard deviation (RSDs) were 0.5%-7.4% in chicken; the recoveries were 75.6%-115.2%, and RSDs were 0.8%-8.9% in pork; the recoveries were 73.7%-117.5%, and RSDs were 0.5%-14.8% in shrimp. The method was applied to the analysis of 60 samples from Guangdong, and the result showed that ofloxacin, ciprofloxacin, enrofloxacin and doxycycline were detected in 4 samples, the maximum content of enrofloxacin and doxycycline in shrimp was 400 μg/kg, the content of doxycycline in chicken was 220 μg/kg, which exceeded the limit value of 100 μg/kg. Conclusion The method was accurate, efficient and simple, synchronous confirmation and quantitative analysis of the residues for chicken, pork and shrimp meat and other musculature of quinolones and tetracyclines, and was suitable for analysis and confirmation in food safety risk monitoring.

Abstract:Objective To analyze special trade concerns(STCs) related to food WTO Committee on Sanitary and Phytosanitary neasures (SPS Committee) and provide recommendations for the solution of China's special trade concerns. Methods Based on STCs data from WTO/SPS Information Management System, SPS STCs annual reports, SPS notifications and news reports between 1995 and 2016, a statistics and descriptive analysis was conducted from diverse perspectives such as the amount of STCs, involved members and focus fields. Results The number of STCs changed irregularly. Both developed and developing members had been paid great attention to the adoption of STC mechanism. However, the involved members had high concentration characteristics. Agro-products were the hot products, while import restriction, maximum limit of pollutants, and inspection and quarantine measures for animal and plants were focus measures. The harmonization with international standards and scientific nature of the measures were flash points. Conclusion The STC is one of the effective and efficient mechanisms to solve international trade conflictions. In view of the status of the international standard organizations and the solving practices of STCs, to intensify international standardization construction, improve the voice in international standard organizations, strive for multilateral cooperation and keep continuous concern on STCs will have a positive influence on solving STCs.

Abstract:Objective This paper reviewed the studies on hydrolyzed milk proteins used in infant formula food, and provides suggestions for research and development, supervision and clinical application of hydrolysate formulas. MethodsRequirements in laws and regulations, clinical trial studies and related researches for hydrolyzed milk proteins and hydrolysate formulas were collected and analyzed. Results Regulations and standards for hydrolyzed milk proteins used in formula food for special medical purposes had been released in China; Codex Alimentarius Commission (CAC) and European Union also had regulations and standards for hydrolyzed milk proteins used in infant formula; The US had a large number of literatures and studies for hypoallergenic infant formulas. The requirements of China Taiwan were in accordance with CAC. The relevant regulations of Australia, New Zealand, Japan and other countries and regions had not been found. Conclusion Scientific institutions should pay attention to the basic research of hydrolyzed milk proteins and hydrolysate formulas. Administration department should improve the standards and regulations.

Abstract:Objective This research explored the spatial distribution and spatial auto-correlation of cadmium content level in crayfish in Qianjiang, Hubei, which aimed to provide basis for optimizing the local crayfish breeding industry. Methods The detection data of 760 samples at 38 sample points were analyzed by the spatial visualization and auto-correlation. Results The crayfish with relative high level of cadmium source from the northwest and south part of Qianjiang, especially guanghuasi in the northwest. The Moran's I was -0.04, and the Z score was -0.10 and the P value was 0.92 (P>0.05). Conclusion The cadmium content in crayfish in Qianjiang didn't present spatial clustering. And the level was lower than the maximal residual level which indicate a favorable breeding environment in Qianjiang.

Abstract:Objective To investigate the levels of six indicator polychlorinated biphenyls (PCBs) in milk samples from some areas of Hubei Province. Methods Thirty locally milk samples were collected in 2014 from some areas of Hubei Province. Concentrations of six indicator PCBs in milk samples were measured by isotope dilution-high resolution gas chromatography-high resolution mass spectrometry (HRGC-HRMS). The daily intake of residents in Hubei Province through milk was calculated and compared with domestic and foreign studies, and the exposure risk was assessed. ResultsThe content of indicator PCBs in milk was 107.2-4 311.2 pg/g fat, the mean and median value was 699.9 and 433.9 pg/g fat, respectively. The compounds with the highest contribution rate in milk samples were PCB-28, followed by PCB-153 and PCB-138. The average and high level (P95) daily intake of residents in Hubei Province through milk is 0.001 47 and 0.005 25 ng/kg BW, respectively. Conclusion The concentrations of indicator PCBs in milk of Hubei were at low level and residents in this province had low health risks through milk intake.

Abstract:Objective To discover the food contamination of lead, cadmium and mercury and provide basic evidence for the risk assessment. Methods According to the surveillance plan during 2012-2016, samples were collected from 12 regions of Inner Mongolia separately. The lead, cadmium and mercury content in food was measured and evaluated according to the national standards. Results Eight kinds of food were monitored during 2012-2016. 4 212 samples were tested for lead. The detection rate was 32.72% (1 378/4 212), and the violation rate was 0.76%(32/4 212). The violation rate was the highest in mushroom, wtih 7.37%(14/190). 4 173 samples were tested for cadmium, the detection rate was 54.18%(2 261/4 173), and the violation rate was 0.58% (24/4 173). The most violations were in mushroom, aquatic products, meat and meat products, with the violation rate of 3.68%(7/190), 2.06%(9/437) and 1.15%(6/524) respectively. 4 217 samples were tested for mercury. The total detection rate was 32.68%(1 378/4 217), total violation rate was 0.50%(21/4 217), the most violation were in mushroom and vegetables. The violation rate was 3.68%(7/190) and 1.01% (11/1 088). Conclusion The evidence showed that mushroom, aquatic products, meat and meat products, vegetables were contaminated by heavy metal in Inner Mongolia.

Abstract:Objective To investigate Vibrio vulnificus contamination in seafood in Beijing region and compare the results between real time flourescence chain reaction (RT-PCR) and VITEK. Methods 105 samples of seafood were randomly collected from Beijing region and were detected by traditional method combined with molecular biology method. Comparison of accuracy between RT-PCR and VITEK identification method was also conducted. Results Among 105 seafood samples, there were 40 Vibrio vulnificus positive samples, and the positive ratio was 38.10%. The positive ratio for shrimp, shellfish and fisd were 52.38% (11/21), 37.88% (25/66) and 22.22%(4/18), respectively. Confirmed by rpoB gene sequencing, the accuracy was 100.00%(40/40) for RT-PCR, and 67.50%(27/40) for VITEK. Conclusion Vibrio vulnificus contamination in seafood was an existing problem in Beijing region. In order to prevent the occurrence of food safety events, an evaluation of the potential risk of Vibrio vulnificus contamination in seafood was in need.

Abstract:Objective To investigate the accumulation of arsenic and heavy metals and to better understand the health risks associated with chemicals in vegetables from China. Methods Statistical characteristics of the concentrations of six elements, i.e., Cu, Pb, Cd, Cr, As and Hg, in vegetables from some areas of China were investigated, and their health risks were assessed using the hazard model recommended by US Environmental Protection Agency, based on the available information regarding the concentrations of arsenic and heavy metals reported in published literatures. Results The Kolmogorov-Smirnov test indicated that all the six elements in three types of vegetables had skewed concentration distributions. And the coefficients of variation of element concentrations are less than 10%. The contents of Cd, As and Hg were significantly different (P<0.05) among rhizome vegetables, leafy vegetables and eggplant vegetables. The contents of Pb and Cr were significantly different (P<0.05) among leafy vegetables and eggplant vegetables. No significant differences (P>0.05) were observed for Cu. The contents of Pb, As and Hg in rhizome and Cd concentration in leafy vegetables were relatively higher, respectively. The linear correlation of Pb-Cd in rhizomes and leafy vegetables were all stronger (P<0.01). The linear correlation of Pb-Cr was stronger in rhizomes vegetables (P<0.01). The pollution indexes showed that the levels of Cu, Cd, Cr and As in three types of vegetables were within the limits of safety. But the levels of Pb and Hg in rhizome vegetables and leafy vegetables belong to slight pollution. The non-carcinogenic risk levels from exposure to arsenic and metals (including Cu, Pb, Cd, Cr and Hg) were separately acceptable in rhizome vegetables and eggplant vegetables. However, health risk assessment indicated that the hazard quotients of Pb in leafy vegetables were 1.780 and 2.020 for adult and children at the 95th percentile, respectively. This indicated that the lead in leafy vegetables had a potentially non-carcinogenic risk via food exposure. Conclusion The pollution of arsenic, copper, mercury, chromium and cadmium in vegetables in China were generally low, but the lead pollution in leaf vegetables should be of concern.

Abstract:Objective The risks of Bacillus cereus in commercial fermented bean curd were compared using the existing modified exponential model, log-logistic and Gamma-Weibull model. Methods The initial contamination level of Bacillus cereus in commercial fermented bean curd was obtained by sampling data from a certain city. The risk of commercial fermented bean curd was calculated according to the modified exponential, log-logistic and Gamma-Weibull models. Results Using the average initial contamination level of Bacillus cereus in commercial fermented bean curd as the consumption dose, the Gamma-Weibull model calculated the risk slightly lower than the other two models. Using the highest initial contamination level as the consumption dose, the Gamma-Weibull model calculated the risk slightly higher than the other two models. Conclusion This study could provide research method and ideas for analyzing the risk of other microorganisms using Bacillus cereus risk assessment as an example.

Abstract:Objective National food safety standards project is the foundation of national food safety standards system. By studying the current characteristics of the national food safety national standards project mechanism, the suggestions and advice for the management of national food safety standards were provided. Methods All national food safety standards project proposals from 2011 to 2016 have been sorted and compared with actual annual planning collected from Secretariat of National Food Safety Standards Review Committee. Results Among the proposals and projects, about 90% proposals failed to be brought into the annual project for reasons including not meeting the principle, not being of priority and inadequate financial support. Meanwhile, the current working mechanism laid a good foundation for perfecting the system of national food safety standards. Conclusion To strengthen the national food safety standards project, the suggestions included addressing food safety issue, better food safety risk surveillance and risk assessment, and capacity building on responsible institutions.

Abstract:Objective To investigate the epidemiological characteristic of a food poisoning in Hebei Province, identify the wild mushroom species causing poisoning, and put forward effective prevention and control measures. Methods The epidemiological investigation, morphological identification and molecular biology identification were used to analyze the poisoning event. Results Eleven people were poisoned due to poisonous mushrooms, there were 3 deaths and the fatality rate was 27.27%. Mushrooms at the construction site were collected, and identified as Amanita subjunquillea, combined with morphological and molecular biology identification method. Conclusion Poisoning event caused by mistaken eating of Amanita subjunquillea was first reported in Hebei. In the future, measures for preventing and controlling poisoning should focus on strengthening the monitoring and health education, reminding people not to eat wild mushrooms.

Abstract:Nowadays, with better living conditions and improved health consciousness, mass fitness has developed rapidly and sports nutrition food has obtained extensive attention. In this paper, the definition and classification of sports nutrition food were introduced. The history of development and current status of sports nutrition food were analyzed. At the same time, the development trends of sports nutrition food in China were predicted. The purpose was to provide reference for the future development of sports nutrition food industry.

Abstract:Vibrio vulnificus widely exists in oysters and seawater. It has been recognized as one of the three major pathogenic Vibrio spp. because of its strong cytotoxicity and hemolysis. In this paper, the contamination status of Vibrio vulnificus in food, prevalence, pathogenicity, pathogenic mechanism and detection method are reviewed, so as to provide theoretical basis for the prevention and treatment of the infection.