Abstract:Since the regulation of health food management in China in 1996， a series of changes have taken place in the functions of health food which were allowed to apply for and approve/register in the past 26 years. The expression and interpretation of function terms/claims have been gradually improved and been more reasonable， which laid a solid foundation for further supervision and market regulation， and reserved space and possibility for the development of new health functions. This paper briefly introduced and reviewd the development and change process of the functions of health food in China， and made some suggestions for the development of new health functions.

Abstract:Objective The sampling method of virus on food packaging surfaces was optimized. The virus recovery rate on different material surfaces was studied by simulating different scenes of virus contamination on the surfaces of frozen food packaging materials.Methods The virus was evenly coated on the surfaces of different materials in different scenarios. Different buffers and different sampling methods were used for sampling residual virus. The virus recovery rate was calculated by virus titer （TCID₅₀）.Results Among the three sample buffers， Hank’s balanced salt solution had the highest virus recovery rate， followed by PBS buffer and MEM media. Among the five sampling methods， the highest recovery was to apply the wet swab once on the surface and then rotated for the next swabing. Using the optimized sampling method to sample virus from the surfaces of different materials， the recovery rates of smooth plastic surface and metal surface were 10.47% and 3.55%， while the living virus of hard plastic surface， thick cardboard surface， kraft paper and wood surface could not be collected. The virus recovery rates of contaminated food on smooth plastic surface before and after frozen were 92.03% and 4.83%， and that of and metal surface were 1.27% and 4.94%. In addition， the recovery rate of hard plastic surface was 2.59% in contaminated food before frozen， and the recovery rate of thick cardboard surface was 1.27% only in the contaminated food after frozen.Conclusion The virvs recovery rates varies depending on the substrate of surfaces. This sampling method is suitable for collecting virus from smooth "hard surfaces". The residual virus on frozen food packaging surfaces can be effectively collected by the sampling method optimized above as well.

Abstract:Objective A sample survey was conducted on the radionuclide content in imported Japaneseinfant milk powder sold by cross-border e-commerce in order to provide basic data for risk assessment.Methods Random sampling was conducted on imported Japanese infant milk powder sold by online cross-border e-commerce， including different brands and types. The strontium-90 activity concentration of milk powder samples was analyzed by HDEHP extraction chromatography （rapid method）， γ radionuclide activity concentration was analyzed by γ energy spectrometer， total αand total β activity concentration was analyzed by low background α， β measuring instrument.Then， the Radionuclide content in infant milk powder was compared with that from Chinese and imported from the Netherlands.Results The artificial γ radionuclides （⁶⁰Co， ¹⁰³Ru， ¹⁰⁶Ru， ¹³¹I， ¹³⁴Cs， ¹³⁷Cs） were not detected in the imported milk powder samples from Japan. strontium-90 activity concentration of 5 milk powder samples imported from Japan was lower than the method detection limit （MDL）. The strontium-90 activity concentration of other samples ranged from 0.13 to 0.18 Bq/kg. Only natural radionuclides ²³⁸U was detected in all samples， which ranged from 33.5 to 109 Bq/kg. The activity concentration of total α and total β ranged from 0.05 to 0.12 Bq/kg. The content of all radionuclides was lower than the limit of Chinese national food safety standards （GB18871—2002 and GB14882—94）.Conclusion The results showed that 60% of the samples of infant milk powder imported from Japan on online cross-border e-commerce platforms were produced in Areas banned from import by China . Although the radionuclide content detected did not exceed China’s limits， considering the limitations of the sampling quantity and scope， consumers still need to be aware of the risk of excessive levels of radionuclides in infant milk powder imported from Janan. With the follow-up measures of the Fukushima nuclear accident， the relevant regulatory authorities still need strengthen random inspection and monitoring.

Abstract:Objective To investigate the contamination levels of nitrate and nitrite in imported cheese products from the Chinese market and assess the health risk of nitrate and nitrite exposure among Chinese adult cheese consumers.Methods Based on the content of nitrate and nitrite in imported cheese products sold in China and the consumption data of cheese food of Chinese residents in 2012， the exposure of dietary nitrate and nitrite of adult cheese consumers in China was estimated by probabilistic assessment method. The exposure results were compared with the acceptable daily intake （ADI） for nitrate directed by the Joint FAO/WHO Expert Committee on Food Additives （JECFA） and the ADI for nitrite directed by the European Food Safety Authority （EFSA）.Results Among 162 imported cheese samples， the detection rate of nitrate was 89.5%， and the average contamination levels was 11.23 mg/kg. The nitrite was detected in only 2 samples， with concentrations of 0.4 and 0.6 mg/kg. The average pollution level of nitrate in different kinds of imported cheese products from high to low was soft cheese， semi-hard cheese， other kinds of cheese and hard cheese. The average exposure of nitrate from imported cheese in Chinese adult was 5.13 μg/kg BW/d， accounting for 0.14% of ADI， and that of high exposure group （P95） was 20.06 μg/kg BW/d， accounting for 0.55% of ADI.Conclusion The detection rate of nitrate in imported cheese products is relatively high， and the content of different types of imported cheese products is different， while the detection rate of nitrite is very low. The health risk of Chinese adult exposed to nitrate through imported cheese is low.

Abstract:Objective To study the use of packaging materials for tea in China and establish the database of surface area to volume ratios （S/V） of different food contact materials for different types of tea.Methods Seven categories and 413 tea samples with different packaging forms were purchased from markets and online stores. Food contact surface area of each sample was determined by direct measurement or via 3D surface area measuring instruments. The S/V was calculated based on the food contact surface area and the quality or specification data of the tea products.Results All the contact materials for tea were made of a single material， and the mean S/V was 93.0 dm²/kg， ranging from 3.5 to 595.6 dm²/kg. 99.8% （412/413） of the S/V was equal or higher than 6.0 dm²/kg， and 87.2% （360/413） was in the range of 6.0-200.0 dm²/kg.Conclusion The S/V of most commercially available tea products in China was higher than 6.0 dm²/kg， a parameter used for risk assessment by European Food Safety Authority （EFSA）. Therefore， using the S/V constructed by this investigation can decrease the uncertainty in the food contact material risk assessment.

Abstract:Objective To investigate the molecular types and antimicrobial resistance of Salmonella isolated from foodborne disease surveillance in Liaoning Province during 2016—2020 and provide reliable scientific basis for the prevention and control of Salmonella infection and antibiotic treatment.Methods A total of 90 strains of Salmonella isolated from clinical diarrhea cases in foodborne disease surveillance in Liaoning Province from 2016 to 2020 were detected for drug sensitivity by broth dilution method. The molecular typing was analysed by pulsed-field gel electrophoresis （PFGE） method. Bionumeries 7.6 software was used to analyze the similarity between strains.Results The 90 Salmonella strains were divided into 13 serotypes， of which Salmonella typhimurium and Salmonella enteritidis were dominant. The 90 strains were divided into 54 PFGE patterns by Xba I. The similarity between each pattern was 51.4%~100%， including 1~10 strains. The same serotype strains had highly similar PFGE pattern， and there was multiple clustering phenomenon. The drug susceptibility results showed that 90 strains of Salmonella showed 36 kinds of drug resistance spectrum.The resistance rate to ampicillin was the highest （66.7%）， followed by that to nalidixic acid （62.2%）. All strains were sensitive to cefoxitin.The overall multi-drug resistance rate reached 48.9% （44/90）， among which the predominant serotypes of Salmonella typhimurium and Salmonella enteritidis were 87.5% and 45.8%.Conclusion The cases of diarrhea caused by Salmonella in Liaoning Province are sporadic， but the trend of multi-drug resistance is obvious， the overall drug resistance rate is relatively high， and the drug resistance spectrum is wide. Traceability and drug resistance monitoring should be further strengthened. It is suggested that molecular tracing and drug resistance surveillance for Salmonella should be further strengthened.

Abstract:Objective To understand the antibiotic residues in ice/fresh chicken collected from retail market and the antibiotic susceptibility of Escherichia coli （E.coli）isolated from these chicken in Henan Province. This study will provide data basis for chicken safety risk assessment.Methods A total of 60 ice/fresh chicken were collected from retail market and tested for antibiotic residues by high performance liquid chromatography-mass spectrometry tandem method from May to November in 2020 in He’nan Province； Totally， 300 E. coli isolates were recovered from these chicken and tested for antibiotic susceptibility by micro-broth dilution method.Results No antibiotic residues were detected in these chicken samples. All the E. coli isolates are susceptible to imipenem. The antibiotic resistant rates of the E. coli isolates to the other 14 antibiotics were from 8% to 86.33%. The antibiotic resistant rate ≥50% were： tetracycline 86.33% （259/300）， ampicillin 69.00% （207/300）， chloramphenicol 63.33% （190/300）， cefazolin 50.67 （152/300）， nalidixic acid 50.00% （150/300）. The proportion of multidrug-resistant organism （MDRO） is up to 81.75% （224/274）. The antibiotic resistance rates were significant difference among different regions （χ²=31.331， P<0.05）. The spectrums of antibiotic resistance of E. coli isolates were scattered， the most popular spectrum was tetracycline （8.39%， 23/274）.Conclusion The antibiotic residues of retail chicken meet the relevant regulations of China government in He’nan Province. E. coli isolates of chicken showed high resistance to antibiotics， and the MDRO are popular in the tested isolates. It is necessary to strengthen supervision of the antibiotic usage in poultry farm to control the antibiotic resistance production.

Abstract:Objective To provide theoretical guidance and decision-making basis for food security in Fuyang district， the levels of lead， cadmium， chromium and arsenic in native rice in Fuyang district in Hangzhou were studied， and the potential risk of eating native rice to human health was evaluated.Methods 450 representative and mature rice samples were collected from 8 areas in Fuyang from 2018 to 2020. The other 50 samples from the supermarket were used as the control group. The pretreatment conditions of microwave digestion were optimized and then the exposure amount of heavy metals were detected according to Chinese national standards. And the risk assessment was carried out by MOS or MOE method.Results The average values of lead， cadmium， chromium and arsenic in native rice samples were 38.0， 180， 83.8， 77.2 μg/k， respectively. The qualified rate of lead， chromium and inorganic arsenic in native rice was 100%. The over-limit rate of cadmium in native rice was 26%， and the qualified rate of commercial rice in control group was 100%. The exposure of lead， cadmium， chromium and arsenic to the health risk of residents were acceptable， and the risk level was Cd>Cr>Pb>As.Conclusion According to the results of dietary risk assessment， the health risk caused by the exposure of four heavy metals to the native rice consumed in Fuyang district is relatively low.

Abstract:Objective To investigate the pesticide residues in vegetables in Inner Mongolia and assess the dietary exposure risk.Methods Using the data of pesticide residues in vegetables from the 2016—2019 risk monitoring in Inner Mongolia， combined with the food consumption data of the residents in Inner Mongolia in the 2012 National Total Diet Study， the food safety index method and the acute dietary intake risk assessment model were used to conduct risk assessments.Results From 2016 to 2019， a total of 9 types and 15 106 vegetable samples were tested. Organophosphorus， organochlorine， carbamate and pyrethroid pesticides were detected. The overall detection rates were 0.98% （72/7 315）， 3.43% （109/3 178）， 4.44% （56/1 261） and 0.30% （10/3 352）， respectively. Among the four categories， there were some samples violating the stardards， including omethoate （0.05%，4/7 315）， phorate （0.16%，12/7 315）， chlorpyrifos （0.10%，7/7 315）， isofenphos-methyl（0.01%）， hydrocarbophos（0.01%）， methamphetamine （0.01%，1/7 315）， procymidone （0.09%，3/3 178）， chlorothalonil （0.03%，1/3 178）， cyhalothrin （0.32%，4/1 261）and amino carbofuran （0.09%，3/3 352）. The assessment results showed that the food safety index （IFS） was less than 1 based on the average pesticide residue concentration Ri， and the risk was acceptable. But there were some risks of phorate， triazophos， methophos， chlorothalonil and cyhalothrin based on the maximum value of Ri. The results of acute exposure assessment showed that there was acute risk with 1.42 mg/kg of phorate in tomatoes.Conclusion All four types of pesticides in vegetables had been detected， and some had exceeded the standard. There were some health risks for phorate， triazophos， methophos， chlorothalonil and cyhalothrin when the food safety index method （IFS） was applied with the maximum value of the pesticide residue concentration Ri. The results of the acute exposure assessment indicate that there was an acute health risk of ingesting phorate through tomatoes. It was recommended that relevant departments strengthen the supervision of the use of prohibited and restricted pesticides to better protect the health of local residents.

Abstract:Objective To analyze the correlation of muti-mycotoxin contamination in wheat， the co-contamination characteristics of different mycotoxins were studied.Methods Data mining analysis of the association between monitoring data for multiple mycotoxins contamination in wheat was performed using the association rule Apriori algorithm. Boolean data type of transaction database was constructed according to the pollutant index values to risk hierarchy structure to mine frequent item sets of transaction database. To determine frequent item sets and obtain strong association rules， minimum threshold support and minimum confidence was set， and iterative connection and pruning operations were performed repeatedly. Association rules were evaluated by confidence， support and promotion degree， etc. Finally， data visualization was applied to association rules to display and verify rules more intuitively.Results The potential strong association rules of co-contamination of muti-mycotoxins in wheat were found， including 9 strong association rules of single common contamination toxin and several strong association rules of combined term sets. The co-pollution relationship between deoxynivalenol and nivalenol， zearalenone and deoxynivalenol was analyzed and verified. The confidence was 92.0% and 80.6%， respectively.Conclusion The strong association rules obtained by data mining have certain significance for the early warning， prevention and control of wheat toxin risk， which provides basis for the assessment of combined exposure to multiple toxins.

Abstract:Objective The advantages and disadvantages of three statistical models commonly used in food contaminant exposure assessment， namely the observed individual means （OIM） model， the beta-abinomial and normal （BBN） model and the non-parametric model were compared by an example of the estimation of long-term exposure to cadmium via rice.Methods Rice， cadmium and diet were used as Chinese and English keywords to search the literature on cadmium concentration in rice in China National Knowledge Infrastructure， Wanfang Data Knowledge Service Platform and PubMed database. Long-term levels of exposure to cadmium via rice for the total population and age groups in China were estimated by combining partial consumption frequency data obtained from the Chinese nutrition survey.Results In the total population， the OIM model showed that the 2.5^th to 97.5^th percentile （P2.5、P97.5） of the exposure to heavy metal Cd in rice was 0.081-0.576 μg/（kg·BW·d）， the non-parametric model result was 0.081-0.573 μg/（kg·BW·d）， and the BBN model result was 0.104-0.611 μg/（kg·BW·d）. The average results of the OIM model， non-parametric model and BBN model in different populations were close. The average values of the three models in the total population were 0.278， 0.277 and 0.278 μg/（kg·BW·d）， respectively.Conclusion With large sample data， non-parametric models have similar assessment results to the OIM model， while BBN models can allow for a more conservative assessment of exposure by subtracting differences in consumption frequency within individuals， and better evaluate the long-term exposure level of pollutants.

Abstract:Objective To estimate the global prevalence and concentration of deoxynivalenol （DON）， aflatoxins （AFs）， zearalenone （ZEN）， nivalenol （NIV）， T-2 toxin （T2）， HT-2 toxin （HT2）， ochratoxin A （OTA）， fumonisins （FBs）， alternariol （AOH）， alternariol monomethyl ether （AME）， tentoxin （TEN） and tenuazonic acid （TeA） in wheat and wheat-based products via Meta-analysis.Methods The databases include PubMed， Web of Science， CNKI and WANFANG database.Results A total of 69 eligible studies were included in this study， related to 22，308 samples. The global pooled prevalence of mycotoxins in wheat and wheat-based products was 58% （95%CI： 51%-66%）， which mainly were TeA （99%）， TEN （88%）， DON （85%）， AFs （57%）， ZEN （42%）， T2 （39%）， AOH （30%）， AME （29%）， NIV （28%）， HT2 （25%）， OTA （21%） and FBs （16%）. The global pooled concentration of mycotoxins in wheat and wheat-based products was 32.80 μg/kg （95%CI： 24.96-43.10 μg/kg）. DON showed the highest concentration （317.53 μg/kg）， followed by TeA （117.37 μg/kg）， FBs （45.09 μg/kg）. The co-occurrence rate of DON-ZEN was 11.0%, 14.0% and 26.7%, TeA-TEN was 16.2%, TeA-TEN-AME was 14.3% and TeA-TEN-AOH-AME was 19.5%, respectively.Conclusion Wheat and wheat-based products showed different characteristics of mycotoxin contamination in different countries or regions, and the co-occurrence rate of more than one mycotoxin in wheat and wheat-based products was high, which should be paid attention to in the combined exposure assessment.

Abstract:Objective To evaluate the equivalence of 5 Salmonella selective enrichment procedures in standard methods worldwide.Methods The growth rates（P_R） and the colony characteristics of 5 selective enrichment broths（SC， TTB， RV， MKTTn， SBG） and 5 selective mediums（CAS， XLD， XLT4， HE， BS） were validated according to the GB4789.28—2013. The sensitivity（SE）， the relative trueness（RT） and the acceptable limit（AL） were estimated on highly contaminated foods through the use of 5 protocols combined with 5 selective enrichment broths and 2 selective mediums according to the method of ISO 16140—2：2016. The sensitivity（Se）， the specificity（Sp）， the positive predictive value（PPV） and the negative predictive value（NPV） were simultaneously determined through the use of 10 compound modes combined with selective enrichment broths and selective mediums according to the classical statistical methods.Results The results showed that SC broth had no efficacy in enriching Salmonella enterica serotype Cholerae and Salmonella enterica serotype Cholerae var. Kunzendorf. The CAS and XLD were significantly better than XLT4， HE and BS in identifying typhoidal Salmonella and nontyphoidal Salmonella as well as the phenotype of hydrogen sulfide.Totally 84 samples（22 pieces of meat， 32 pieces of poultry and 30 pieces of aquatic products） were tested. 25 out of the 84（29.76%） were confirmed positive by 5 protocols， and 16 serotypes from 42 isolates were identified. The SE of 5 protocols were 84.00%， 100.00%， 88.00%，88.00% and 92.00%， respectively， but showed no statistically significant difference between each other. The AL of one protocol （SC+TTB） went beyond the limitation of the ISO 16140—2：2016 due to the ineffectiveness of SC broth. The compound mode of RV-CAS had the best comprehensive benefits， while the Se， the Sp， the PPV and the NPV of which were 68.00%， 95.00%， 85.00% and 88.00%， respectively.Conclusion The ineffectiveness of SC broth reduces the sensitivity of the detection protocol for Salmonella， which could cause a negative deviation， resulting in the threshold exceeding of the Acceptability Limit （AL）. The combinational selective enrichment broth of RV-CAS is recommended to be the optimal mode， with CAS+XLD being recommended to be the optimal selective medium combination. The process of Salmonella serotyping is suggested to be improved in the standard of GB4789.4 to cope with the multi-serotype Salmonella contamination in food chain and be consistent with the international standardization for food microbiology.

Abstract:Objective To study the effects of Hericium erinaceus polysaccharide on the microstructure， cytokine secretion， antioxidant function， cell proliferation and apoptosis of thymus and spleen in mice with immune stress induced by lipopolysaccharide （LPS）， so as to provide reference for the application of Hericium erinaceus polysaccharide in relieving stress.Methods Fifty male Kunming mice of 12-week old were randomly divided into control group， model group and experimental group I - III （n = 10）. In addition to the control group， the other four groups were intraperitoneally injected with 0.6 mL/kg/d LPS （once a day） three days before the end of the experiment. The experimental groups I， II and III were given 80， 160 and 320 mg/kg Hericium erinaceus polysaccharide by gavage for 2 weeks.Results Compared with the control group， the levels of interleukin-1 β （IL-1β）， interleukin-4 （IL-4） and interferon γ （IFN- γ） in thymus and spleen of mice in the model group were significantly increased （P<0.05 or P<0.01）， the activities of total superoxide dismutase （T-SOD） and total antioxidant capacity （T-AOC） were significantly decreased （P<0.05）， the content of glutathione peroxidase （GSH-Px） was also significantly decreased （P<0.05）， and the content of malondialdehyde （MDA） was significantly increased （P<0.05）. The expression of proliferating cell nuclear antigen （PCNA） mRNA in spleen of mice was significantly decreased （P<0.05）， while the expression of cysteine protease-3 （caspase-3） mRNA was significantly increased （P<0.05）. Compared with the model group， IL-1β， IL-4 and IFN-γ in thymus and spleen of mice in experimental group III was significantly higher， the activity or content of T-SOD， T-AOC and GSH Px were increased significantly （P<0.05）， and the content of MDA and the expression of caspase-3 mRNA were significantly decreased （P<0.05）. By histological observation， compared with the model group， the microstructure of thymus and spleen in experimental group Ⅲ was significantly improved， the thickness of thymic cortex was increased （P<0.01）， and the thickness of splenic nodule and periarterial lymphatic sheath was decreased （P<0.05 or P<0.01）.Conclusion Supplementation of 320 mg/kg Hericium erinaceus polysaccharide can significantly improve the damage of thymus and spleen microstructure， inhibit the secretion of pro-inflammatory cytokines and the expression of apoptosis genes induced by immune stress， and enhance the activity of antioxidant enzymes.

Abstract:Objective The purpose of this study was to provide basis for the revision of GB 4789.28—2013 and the quality control of culture media by screening the quality control strains of culture media for salmonella test.Methods The strains specified in GB 4789.28 and 9 salmonella strains（Salmonella newport， salmonclla Infantis， Salmonella choleraesuis， Salmonella blegdam， Salmonella kottbus， Salmonella arizona， Salmonella dublin， Salmonella agona， Salmonella. anatis） isolated from real food were used to test the growth rate and selectivity of 10 different brands of media including Rappaport Vassiliadis Salmonella Enrichment， Selenite Cystine Broth， Tetrathionate Broth Base enriched broth， Bismuth Sulfite Agar， Hektoen Enteric Agar， Xylose Lysine Desoxycholate Agar by quantitative and semi-quantitative methods. It was evaluated whether the quality control strain used in GB4789.28—2013 could meet the quality control of salmonella media.Results The results showed that the growth rate and selectivity of different media brands were different when the same strain was used， and Salmonella choleraesuis and Salmonella arizonae had higher requirements on the quality of media.Conclusion It is suggested that medium production enterprises and microbiology laboratories should use strains isolated from food with higher quality requirement in medium testing， and the quality control methods should be highly standardized to ensure the stability and reliability of test data.

Abstract:Objective To detect the genotoxicity of Coreopsis tinctoria Nutt.（water extract） and provide research data for its safety evaluation.Methods The water extract of Coreopsis tinctoria Nutt. was used as the test substance in bacterial reverse mutation test， mouse lymphoma Assay （MLA） with and without metabolic activation S9； and the powder of Coreopsis tinctoria Nutt. was used in micronucleus test. Ames test based on the plate incorporation method was performed to detect his^-/trp^- revert mutation capabilities of S．typhimurium TA98， TA100， TA1535， TA1537 and E．coli WP2 uvrA induced under four doses of 1.25， 2.5， 5 and 10 mg/ plate； MLA based on the microporous method was performed to detect the increase of tk^-+/- mutation frequency （MF） of L5178Y cells induced by 5 concentrations of 1.5， 2.0， 2.5， 3.0 and 3.5 mg/mL under the treatment condition of ±S9/3 h， and to evaluate the damage effects on the tested cells； for the mouse bone marrow micronucleus test： CD-1 mice were administrated with 900 mg/kg， 1 800 mg/kg and 3 600 mg/kg of the Coreopsis tinctoria Nutt. powder （200 mesh） intragastrically for three times at an interval of 24 h， and the samples were collected by 18-24 h after the last dose. The micronucleated cells in 2 000 polychromatic erythrocytes were counted， and the micronucleated cell rate were calculated.Results Under both conditions absent and present S9， the numbers of the revertants in five strains induced by 1.25~10 mg/dish （equivalent to crude drug： 8.33~66.67 mg/plate） were not significantly increased compared with the negative （solvent） control of sterilized water for injection. The MF induced by 1.5~3.5 mg/mL （equivalent to crude drug： 10~23.33 mg/mL） were significantly increased with a concentration-response relationship， and most of the mutants were in the form of small colony. The T-MF and S-MF induced by 3.0 and 3.5 mg/mL +S9 groups were more than 3 times of the negative control group： the mean micronucleus rates in 900 mg/kg， 1 800 mg/kg and 3 600 mg/kg groups were 0.85±0.58， 1.10±0.97 and 1.45±1.12， respectively， with no significant difference compared with the deionized water negative control group.Conclusion The water extract of Coreopsis tinctoria Nutt. could significantly increase the mutation frequency of tk^+/- gene and led to chromosome damage in L5178Y cells， no matter with or without metabolic activation， suggesting its potential genotoxicity to human.

Abstract:Objective To study the effects of the kind and concentration of antibiotics in pre-enrichment for the detection of Shiga toxin-producing Escherichia coli （STEC） in the current international standard method.Methods The minimal inhibitory concentrations （MICs） of three antimicrobials supplemented in an STEC enrichment broth of four official methods were measured through testing of a panel of STEC and non-STEC isolates.Results There were differences among different antibiotics for the inhibition of STEC. At the recommended concentration， acriflavine and cefsulodin inhibited the growth of stx1a and stx2b subtypes of STEC， while novobiocin inhibited the growth of stx1a， stx1c， stx1d， stx2b， stx2d， stx2e， stx2f and stx2g subtypes of STEC. In addition， there was no significant difference among MICs of STEC and other gram-negative bacteria to acriflavine， cefsulodin and novobiocin （P>0.05）. MICs of gram-positive strains to three tested antimicrobials were significantly lower than those of gram-negative bacteria （P<0.01）.Conclusion The data provided valuable evidence for the STEC enrichment method development and improvement.

Abstract:Objective To reduce the content of cadmium in rice， the method of cadmium removal from rice was established and the extraction conditions were optimized by response surface methodology.Methods The cadmium extraction rate was used as the index to screen the cadmium removal methods. Commercially available cadmium positive rice was chosen as the test sample and four kinds of food grade organic weak acids were chosen as extractants. The concentration of acid solution， extraction time， solid-liquid ratio and rice powder particle size were used as independent variables to carry out the single factor extraction. And the optimal conditions for removing cadmium from rice was obtained by response surface design.Results The optimal conditions for removing cadmium from rice were 4.2% acetic acid solution， 11 min extraction， liquid-to-material ratio 13：1 （mL/g）， and at least 50 mesh for rice flour. Under these conditions， the average removal rate of cadmium in rice was 98.67%.Conclusion The experimental model is reasonable and the optimized extraction method is feasible. The removal or reduction of cadmium in raw rice is realized with optimal cadmium extraction conditions， which provides a scientific method for the research on cadmium removal from cadmium-contaminated rice.

Abstract:Objective To develop a novel ELISA for sensitive and naked-eye detection of danofloxacin （DAN）.Methods Based on TYR signal amplification， a novel ELISA was developed for sensitive detection of DAN. Analytical performance of the method was conducted by sensitivity and specificity experiments. The method was used for detecting DAN-spiked chicken and pork samples to verify.Results This method could be used to qualitatively detect DAN with naked eyes at a cut-off value of 0.4 ng/mL， which was 25-fold lower than that of the traditional ELISA （10 ng/mL）. The method exhibited no cross-reaction of DAN with six other drugs in buffer. The method was successfully used for detecting DAN-spiked chicken and pork samples.Conclusion The developed novel ELISA exhibits high sensitivity and specificity， and can be used for the danofloxacin detection in actual samples by naked eye.

Abstract:Objective To establish a nucleic acid immunochromatography method for rapid detection of Enteroinvasive Escherichia coli （EIEC）.Methods The target single-stranded DNA was prepared by asymmetric PCR， the invE which was the virulence gene of EIEC and uidA which was the marker gene of Escherichia coli were detected by immunochromatography.Results In the asymmetric PCR system， the optimal ratio of forward and reverse primer for uidA and invE was 1∶3， and the optimal primer concentrations （reverse primer） were 0.2 μmol/L and 0.25 μmol/L， respectively. The optimal cycle number of amplification was 40. The lowest detection limit of this method was 3.97 × 10^-3 ng/μL， and the specificity was comparable to that of PCR-gel electrophoresis.Conclusion The method which had the advantages of convenience， less time consuming， low detection cost， good accuracy and specificity， was suitable for primary laboratory.

Abstract:Objective An online fully automated alkaline hydrolysis method for the determination of chloropropanol esters （MCPDE） and glycidyl esters （GE） in edible oils and fats was developed， and the effects of vegetable oil type and temperature on the conversion of GE to 3-chloro-1，2-propanediol （3-MCPD） were investigated.Methods Based on the basic principles of AOCS Cd 29c-13， the samples were subjected to hydrolysis， chlorination， liquid-liquid extraction and derivatization on a fully automated sample pretreatment platform， and then separated by a DB-5MS column after injection. The data was determined by multiple reaction monitoring mode （MRM） coupled with the internal standard method.Results The efficiency of GE conversion to 3-MCPDE in the five vegetable oils was significant different. However， the effect of temperature was relatively greater. The alkali hydrolysis time was optimized， and the hydrolysis of MCPDE and GE was basically completed when the hydrolysis was carried out for 7 min at 10℃. The limits of detection for 2-chloro-1，3-propanediol （2-MCPDE）， 3-chloro-1，2-propanediol （3-MCPDE） and GE were all 5 μg/kg calculated by their free forms. There was a good linear relationship between the concentration and ratio of the response ranged from 0 to 0.4 μg/mL. When spiked from 20 to 2 500 μg/kg， the recoveries of MCPDE and GE ranged from 90.3% to 109.7% with the relative standard deviation （n=6） of 1.3%-7.7%， indicating that the precision was better than that of the manual procedure. The method was comparable with the Chinese national standard method for food safety under reviewed and was successfully applied to the determination of FAPAS proficiency test samples.Conclusion The novel automatic procedure has the advantages of simple operation and high sensitivity， which reduces the labor intensity， improves the detection efficiency and repeatability compared with the reported manual procedure， and can better meet the requirement for quantification of MCPDE and GE in edible oils and fats.

Abstract:Objective To establish a dual real-time PCR rapid detection method for sole fish and Pangasius bocourti-derived components.Methods Universal TaqMan primers and probe sets were designed according to the mitochondrial 16S rRNA gene sequence of 13 species of sole fish. TaqMan primers and probe sets were designed according to the mitochondrial cytb gene sequence of Pangasius bocourti， and the amplification reaction system was optimized for real-time PCR to achieve the purpose of rapid detection of products.Results This method had good specificity， and the sensitivity could reach 10^-3 ng sole fish DNA. Sole fish 16S rRNA gene could be detected in fish products mixed with carp meal， and the mass fraction sensitivity could reach 1%. The sensitivity could reach 10^-4 ng Pangasius bocourti DNA. Pangasius bocourti cytb gene could be detected in fish products mixed with sole fish， atlantic cod meal and rice noodles， the mass fraction sensitivity of sole fish and atlantic cod meal could reach 0.1%， and the mass fraction sensitivity of rice noodles could reach 0.001%.Conclusion This method had high specificity， high speed and high sensitivity， and could meet the detection requirements of sole fish authenticity and Pangasius bocourti adulteration in fish meat products.

Abstract:Objective To establish a method for the determination of arsenic compounds in poultry food by high performance liquid chromatography-inductively coupled plasma mass spectrometry（HPLC-ICP-MS）.Methods The sample was microwave assisted extracted by 10% methanol and 1% nitric acid．Ten arsenic compounds were separated by DIonexIonPac As7（4 mm×250 mm） anion exchange column with 0.5-200 mmol/L ammonium carbonate for gradient elution.Results The linear ranges for 10 arsenic compounds were between 1-20 μg/L with the linear coefficients（r） more than 0.999 0，and the detection limits of the method were between 0.24-0.80 μg/kg. The relative standard deviations （RSDs） of precision ranged from 1.0% to 5.7%. The recoveries were 83.77%-114.21% in chicken and beef substrate， spiked with the three levels.Conclusion With high sensitivity， simplicity for pretreatment， good reproducibility and accuracy， the method was suitable for the determination of ten arsenic compounds in poultry food.

Abstract:Platelet over-activation is one of the important mechanisms of atherosclerosis （AS） in diabetes mellitus. Dietary nutrient intervention plays an important role in the primary prevention and treatment of diabetes mellitus combined with AS. Studies have shown that the antiplatelet factor in tomato extract can inhibit platelet aggregation and activation in different environments. Its bioactive ingredient are nucleosides and derivatives and phenolic compounds， which retard the pathological progress of diabetes mellitus complicated with AS. This review aims to explore the mechanism of the antiplatelet effect of tomato extract， and to provide a theoretical basis for the prevention and treatment of diabetes mellitus complicated with AS.

Abstract:Based on the background of building a food safety assurance system for sustainable supply chain， combined with Hazard Analysis Critical Control Point （HACCP） and the current status of the development and application of HACCP certification， the role of HACCP in the construction of a sustainable food supply chain was preliminarily analyzed. In order to provide a theoretical basis for certification bodies and management departments to effectively implement HACCP certification， and make HACCP certification an important tool for the market to regulate the allocation of food safety management resources， recommendations for the development of HACCP certification was put forward.

Abstract:Codex Alimentarius Commission had published the latest version of “General principles of food hygiene （CXC 1-1969）” on 23^th November， 2020， which was significantly meaningful for the development of food safety management and HACCP principle. Furthermore， CXC 1-1969 was considered as the reference for the composition of the 2021 “Hazard analysis and critical control point （HACCP） system certification accreditation regulation” published by the Certification and Accreditation Administration of China on 30^th July， 2021. The update of CXC 1-1969 extended the connotation of Good Hygiene Practices （GHPs） by examples and explanation as well as clearly defined the differences of preventive controls between GHPs and critical control points （CCPs）. In addition， the updated version added food safety key issues， such as allergen management and food safety culture. This article explains the change details of CXC 1-1969 by contrasting with the 2003 version and provides ideas to the development and application of HACCP system in China.

Abstract:Objective The current management system of provincial food safety standards were analyzed and suggestions were made.Methods Based on the management system of provincial food safety standards in 20 provinces， the review committee， scope of provincial food safety standard， time limit for public comment， review process， re-audit were mainly analyzed.Results 18 provinces have review committee and stipulated scope of provincial food safety standard to varying degrees. Public comment period of 15 provinces is one month or two months. 20 provinces stipulate to review standard for 1-4 times. 18 provinces have re-audit.Conclusion The review committee should be set in the management system of provincial food safety standards. Scope of provincial food safety standard should be stipulated. The time limit for public comment should be not less than one month. Review standard should be no less than three times. Re-audit process can be removed. To ensure the effective management of provincial food safety standards， the other management should be set according to the relevant laws and regulations and regional characteristics.

Abstract:Objective To understand the current situation and existing problems of the food safety risk monitoring ability of CDC at all levels in Jiangxi Province， and provide basis for further improving.Methods The basic information， personnel allocation， testing ability and personnel training of CDC at all levels in Jiangxi Province were investigated by self-filled questionnaire survey.Results A total of 97 CDCs at all levels were investigated in Jiangxi Province， among which 43 CDCs at county （district） level did not obtain qualification certification. The average area of the provincial CDC was 3 495 m²， and the average laboratory area was 968 m². There were 1 091 people engaged in food related activities in the provincial CDC， mainly technical personnels， accounting for 75%； The composition characteristics of technical personnels and quality management personnels were basically the same： bachelor’s degree， more than 6 years experience， 30-50 years old personnels accounted for the highest proportion. The overall monitoring capacity of CDCs in the province was weak. Except for the provincial level， the average food detection capacity of CDCs at city and county （district） level didn’t meet the national requirements. In 2018， a total of 1 430 training was received in the province， with an average 1.3 training per person per year.Conclusion In Jiangxi Province， the talent team construction of CDC at all levels needs to be strengthened， and it is urgent to expand the staff team of CDC at local level， especially to improve the proportion of highly educated talents. The monitoring capacity needs to be improved， and the passing rate of certification of inspection and testing institutions of county （district） level CDC institutions needs to be improved.

Abstract:Objective To understand the public’s ability to distinguish online food and drug rumors and false publicity， so as to prevent the spread of rumors and maintain social stability.Methods A questionnaire survey， by the method of random sampling， was conducted on the public’s ability to identify food and drug online rumors and false publicity in a minority autonomous prefecture of Guizhou Province in China.Results The identification ability of online rumors and false propaganda about food and drug on the local public was generally low. The adolescents in economically underdeveloped areas have weak ability to identify network rumors and false propaganda. Most of the public are rational in dealing with online food and drug safety information， they prefer to learn about information through the authoritative websites of national regulatory authorities， basically have the subjective consciousness of confirming the authenticity of information， but lack the action ability to dispel rumors.Conclusion The management of food and drug online rumors and false publicity should be strengthened. We should pay more attention on monitoring， systematic analysis， targeted and predictive governance and popular science activities.

Abstract:Objective To provide reference for formulating effective supervision and management strategies， the overall situation of food safety in Tangshan was analyzed.Methods The food safety supervision and inspection in Tangshan from 2018 to 2020 were summarized， and the problems were analyzed.Results 120 744 batches of food samples were inspected from 2018 to 2020. 3 046 batches of unqualified food samples were found， and the unqualified rate was 2.52%. The main food safety problems were the use of food additives beyond the scope and limit and microbial pollution. Among the 33 product categories， the unqualified rate of tableware was 25.61%， which was more prominent. The unqualified reason might be that tableware has not been thoroughly disinfected or improperly cleaned after disinfection.Conclusion Inspection is an effective means to provides clues for effective supervision and clarify the key supervision area and requirements.

Abstract:Objective The results of follow-up evaluation of GB 2757—2012 National Food Safety Standard- Distilled Wines and Mixed Wines were analyzed to reveal the main problems in the implementation of the standard and provide the basis for revision.Methods The comments of “Normal Tracking Evaluation” section on the national food safety standard follow-up evaluation platform were collected. The data was input to the Excel 2019 software for analysis. The key issues were discussed to provide suggestions for the revision of the standard.Results 827 valid comments were received. When "no comment" was rejected， 47.95% of the comments were focused on "physicochemical indexes" including methanol and cyanide indicators. It was suggested that some other issues were worthy of attention and research， such as the microbiological risk of mixed wines， new categorization， characteristic index and physicochemical indexes.Conclusion The comments reflects the key issues in the implementation of GB 2757—2012. The revision of standards should be timely started on the basis of scientific evaluation in the future. At the same time， it is suggested that the publicity， training and consultation should be strenghtened to improve understanding and applying of the standard.

Abstract:Objective To provide basis for further improvement of China's national food safety standards system， the special follow-up evaluation results of national food safety standards in 2020 were analyzed， and the comprehensive evaluation of standards by regulatory authorities， industry enterprises and other parties were systematically understood.Methods Opinions were collected through the online questionnaire survey. Excel 2016 was used to sort out the collected comments and descriptive statistical analysis. Meanwhile， the results were compared with those of 2019 to get the trend analysis results.Results A total of 17 074 special follow-up evaluation questionnaires of national food safety standards were collected on the online platform， with the highest participation of personnel from food production and operation enterprises， accounting for 50.1%（5 917/11 810） of the total number of valid questionnaires. 93.0%（9 363/10 067） of the respondents thought that the food categories could be clearly positioned in the current general food safety standards. 84.2%（9 942/11 810） and 61.5%（7 260/11 809） of the respondents thought that there were corresponding food product standards and code of practice standards， respectively. The comprehensive score of product standards was 4.41， and the comprehensive score of code of practice standards was 4.42.Conclusion China’s current food safety standards system framework is basically established. All parties are generally satisfied with China’s national food safety standards system， but there are still some problems in the standards system that need to be further improved. It is suggested to carry out the food safety standards follow-up evaluation in depth and make full use of its results， and improve the national food safety standards system in the future.

Abstract:Objective To study the traceability status of food pollution and foodborne diseases caused Salmonella covalis （S.covalis） in He’nan province from 2016 to 2020.Methods 22 strains of S.corvallis from foods and 5 strains from diarrhea patients were isolated from 2016 to 2020 in He’nan Province. Serotyping， drug susceptibility test and PFGE molecular typing were carried out according to the National Food Safety Risk Monitoring Manual. PFGE and susceptibility data were clustered using BioNumerics 7.6 software package.Results 22 strains of foodborne S.corvallis were all from fresh meat. According to results of drug susceptibility test， the multiple drug resistance of foodborne strains was not very serious， while the drug resistance spectrum of strains from diarrhea patients was complex， some were sensitive strains and two strains of them were super resistant bacteria with 13 multiple drug resistance. According to the results of PFGE molecular typing， there were high similarities among food strains in the same region in the same period， suggesting the probability of aggregation of contaminated food in a certain area in summer. According to the comparison and tracing of diarrhea patient strains and food strains， there was no disease directly caused by food， and the disease was caused probably after transmission.Conclusion Food safety risk monitoring data can provide effective clues for market supervision， the popularization and application of drug resistance monitoring and molecular typing technology has promoted the traceability and precise prevention of foodborne diseases， and greatly achieved the goals of disease prevention and health protection.

Abstract:Objective To investigate a black fungus poisoning incident in Shenzhen and identify the specie of pathogen. Meanwhile， the toxogenic strains， the distribution and metabolism of bongkrekic acid （BA） in vivo were also studied to provide references for treatments of similar incidents.Methods Isolation and identification of pathogenic bacteria were carried out according to GB/T 4789.29-2003. MALDI-TOF MS was also used. UPLC-QTRAP-MS/MS was used for determination of BA in Black Fungus， blood， liver， urine， bacterial suspension and other samples.Results Different concentrations of BA were found in soaked Black Fungus， blood and urine samples. BA was also found in necrotic liver acquired from liver transplant 5 days after BA intake. Continuous surveillance showed that certain concentration of BA still exist in patient’s blood and urine even 9 days after BA intake. Burkholderia gladioli were isolated from both dried and soaked Black Fungus， and both two strains produced abundant BA after bacilli-culture.Conclusion Burkholderia gladioli in the Black Fungus produced large amount of BA during the soaking process. Then BA was ingested by the patient and widely distribute in vivo. Consequently， the patient died of multiple organ failure.

Abstract:Objective To analyze the epidemiological characteristics of mushroom poisoning events in Guangxi， and provide scientific evidence for the control and prevention strategy.Methods The descriptive analysis was conducted on the incidence data of mushroom poisoning events in Guangxi reported through the Foodborne Disease Outbreak Reporting System from 2015 to 2020.Results A total of 189 mushroom poisoning events were reported with 789 poisoning cases and 10 deaths in Guangxi from 2015 to 2020. The case fatality was 1.27%. The highest number of food poisoning incidents was found in 2020， accounting for 38.10%（72/189） of the total. The majority of the mushroom poisoning events occurred from May to September. Guilin， Baise， Wuzhou and Qinzhou were areas of high incidence of mushroom poisoning events. Family was the main places for mushroom poisoning events， accounting for 93.65%（177/189）of the total.Conclusion The prevention and control strategies of mushroom poisoning in Guangxi should be formulated according to the characteristics of high-incidence seasons， high-incidence areas and high-risk populations， and the publicity and education of families in rural areas should be strengthened to improve the public awareness of prevention.

Abstract:Objective To provide scientific basis for early warning and prevention， the epidemic characteristics of mushroom poisoning in Hubei Province from 2016 to 2020 were analyzed.Methods The epidemiological characteristics of mushroom poisoning incidents reported by the food-borne disease outbreak surveillance system in Hubei Province from 2016 to 2020 were analyzed.Results A total of 163 cases of poisonous mushroom poisoning were reported in Hubei Province from 2016 to 2020， with 487 cases and 17 deaths， with a case fatality rate of 3.49%（17/487）. The largest number of incidents occurred in 2020， accounting for 34.36% （56/163） of the total. Poisonous mushroom poisoning mainly occurred from June to October. Enshi Prefecture and Yichang City were the areas with high incidence of poisonous mushroom poisoning， and households were the main sources of poisonous mushroom poisoning places that occurred accounted for 93.87%（153/163） of the total number of incidents. The proportion of rural poisonous mushroom poisoning incidents was much higher than that in urban areas， and accidental picking and eating was the only cause of poisoning mushroom poisoning.Conclusion Poisonous mushroom poisoning is the main cause of death from food-borne disease outbreaks in Hubei Province. Publicity and education should be carried out in key areas for the high-level populations during the high-incidence season. Wild mushrooms should not be picked or eaten.

Abstract:Objective To learn the epidemiological features of foodborne disease in Baiyun District， Guangzhou City from 2018 to 2020， so as to provide scientific basis for the development of targeted prevention and control measures.Methods The descriptive analysis method was used to analyze the data of 1 226 cases of foodborne diseases reported by surveillance hospitals in Baiyun District， Guangzhou City from 2018 to 2020. The epidemiological and clinical characteristics were described， and the Logistic regression analysis was conducted on the influencing factors of timely outpatient rate.Results From 2018 to 2020， there were 567 cases of foodborne diseases in males （46.25%， 567/1 226） and 659 cases in females （53.75%，659/1 226） in Baiyun District， Guangzhou City. The age of cases mainly ranged from 21 to 30 years old （37.19%，456/1 226）. The occupational distribution of cases was dominated by civil servants， employees of enterprises and institutions. The peak period was June to October. Family（41.80%， 754/1 804） was the main suspicious eating place. Meat and meat products were the main types of suspect foods. Catering service industry was the main processing and packaging method. Multivariate Logistic regression showed that old age， high hospital grade， vomiting times were positively correlated with the timeliness of health-seeking， diarrhea and diarrhea times were more negatively correlated.Conclusion The high incidence of foodborne diseases in Baiyun District， Cuangzhou City was in hot seasons， and families and food service organizations were the high risk places. Food safety supervision and health education should be further targeted to prevent and control the occurrence and prevalence of food-borne diseases．

Abstract:Objective To reveal the research hotspots， current situation and development trend of food safety risks in China by analyzing the basic information of relevant literatures， and to lay a theoretical foundation for future research.Methods In this paper， the literature related to food safety risk collected by CNKI， Wanfang Data and VIP was used as the data source， and the research topic was determined by means of co-word analysis， factor analysis， cluster analysis and strategic coordinate analysis of high-frequency keywords.Results Through cluster analysis of 85 high-frequency keywords selected by SPSS26.0， 9 mainstream research hotspots have been formed in China， which were： food contamination and related risk monitoring， health risks of vegetable pesticide residues， genetically modified food and related legal supervision， risk prevention and early warning， factors affecting consumer perception of risk， risk analysis of food supply chain quality and safety， national food safety standards， food safety risk supervision， safety testing and guarantee.Conclusion At present， a relatively mature research focus in this field is food safety risk regulation. Theoretical researches mostly focus on the objectives， functions， systems and technologies of food safety regulation in China. It is necessary to strengthen the publicity and training of relevant food safety standards of regulatory authorities， so as to improve the food safety supervision and governance ability of grassroots. As an emerging research topic， vegetable pesticide residues and risk prevention and early warning have great development potential in the future. Follow-up research should solve the current situation of lack of relevant monitoring conditions at the grassroots level， and build and improve the risk early warning system as soon as possible.

Abstract:Aptamers are DNA or RNA molecules that can bind to their target molecules with high affinity and specificity， and because aptamers are stable， simply synthesized and chemically modified， aptamers have become useful tools for analytical， diagnostic and therapeutic applications. This article reviews the application examples of aptamers on the detection of foodborne pathogens， biotoxins， heavy metal ions， drug residues， illegal additives and other harmful factors in food， and provides the application prospects of aptamers on food safety detection.