OBJECTIVETo study the relationship between foodborne diseases (FBD) and contamination of Salmonella spp. in catering foods, quantitative microbiological risk assessment (QMRA) of Salmonella spp. was used to evaluate the food material or the ready to eat food.

METHODSThe contamination data of Salmonella spp. in 10 896 food samples of 9 categories of food which were collected by National Food Contamination and Food Borne Disease Surveillance Net, combining with diet consumption data from National Food Nutrition Survey in 2002, were analyzed by the microbiological risk assessment model developed by WHO/FAO or FDA/FSIS of US to predict probability of FBD.

RESULTSThe results of MRA showed that the probability of salmonellosis by consuming ready to eat meat in summer and autumn was 0.20, much higher than the other foods. Although the contamination level in raw poultry was higher than meat, the probability of salmonellosis by raw poultry (9.11 x 10(-6)) was lower than meat (3.14 x 10(-5)) because of the low consumption volume.

CONCLUSIONProbability of FBD was significantly correlated with the volume of food consumption, the status of economy and bacteria contamination level. The level of FBD in summer season was higher than in winter and spring because of ambient temperature.

Food Contamination ; Food Microbiology ; Humans ; Risk Assessment ; Salmonella ; isolation & purification ; Salmonella Food Poisoning ; prevention & control

Animals ; Chickens ; microbiology ; Food Contamination ; prevention & control ; Salmonella ; isolation & purification

OBJECTIVETo improve the mini-modified semi solid rappaport vassiliadis most probable number (mini-MSRV MPN) method for Salmonella detection.

METHODSBased on the mini-MSRV MPN method,Buffered Peptone Water (BPW) was modified as one step enrichment medium and Modified Semi Solid Rappaport Vassiliadis (MSRV) medium was ameliorated as modified MSRV for Salmonella detection under standard Salmonella addition recovery. A total of 154 raw chicken samples, 48 swabs of pheasantry and 48 poultry dung samples were collected to compare the detection results of Salmonella by using improved mini-MSRV MPN, mini-MSRV MPN and regular most probable number (MPN) method.

RESULTSSalmonella recovery was < 2.7 MPN/g when the standard Salmonella addition was at the concentration of 0.9 CFU/g when the mini-MSRV MPN method was employed. If the standard Salmonella addition were at 9.0 and 90.0 CFU/g, the recoveries of bacteria were 10.1 and 94.0 MPN/g, and the average recovery rate was 112% and 104%, respectively. Salmonella detection rate of modified mini-MSRV MPN, mini-MSRV MPN and regular MPN method was 18.4% (46/250), 5.2% (13/250) and 6.0% (15/250), respectively. The detection rate was higher for modified mini-MSRV MPN method than of the other two methods (χ(2) values were 19.68 and 17.82, respectively, all P values < 0.05). The detection quantity of Salmonella (medians were 21.0, < 2.7 and < 3.0 MPN/g, respectively). The quantity detected by modified mini-MSRV MPN method was higher than that of the other two methods (both Z values were 5.71, both P values < 0.05).

CONCLUSIONModified mini-MSRV MPN method is an accurate method for foodborne Salmonella detection.

Animals ; Chickens ; microbiology ; Culture Media ; Food Contamination ; analysis ; Food Inspection ; methods ; Salmonella ; isolation & purification

OBJECTIVETo prepare a DNA Microarray that can detect 8 common species of food borne bacterial pathogens in south China.

METHODSAll the 70mer oligo probes were designed on the characteristic genome loci of the 8 species of food borne bacterial pathogens. Eight subarrays corresponding to the 8 food borne bacterial pathogens were spotted onto the slide and integrated into a pan-array on the chip. A number of identified and known bacterial samples from the storage bank were selected for the validation test.

RESULTSBased on the PPR ranking, for LM sub-array, the PPR of the 3 Listeria bacteria LM, Lin and Liv was 68.8%, 51.8% and 59.6%, respectively, while that of the non-Listeria bacterial samples was all below 43%. For VC sub-array, the PPR of VC sample was 54.1% and that of the non-VC bacterial samples was lower than 17.2%. For VP sub-array, the PPR was 66.7% for VP sample and below 24.2% for non-VP bacterial samples. For Sal sub-array, the PPR was 55.9% for Sal sample and below 50.5% for non-Sal bacterial samples. For Shi sub-array, the PPR of Shi sample and the non-Shi bacterial samples was 53.8% and below 36.6%, respectively. For SA sub-array, the PPR of SA sample and non-SA bacterial samples was 65.2% and below 22.7%, respectively. For CJ sub-array, the PPR of the 2 Campylobacter bacteria CJ and CC were 88.2% and 58.8%, respectively, and that of the non-Campylobacter bacterial samples was lower than 35.3%. For EC sub-array, the PPR of EC sample was 47.9%, and that of the non-EC bacterial samples was lower than 41.6%. Evaluation of the Biosafood-8 chip developed in this study by 18 biological samples from different origins demonstrated its good specificity and accuracy in the identification of the pathogens.

CONCLUSIONThe chip we developed can clearly differentiate the target food borne pathogenic bacteria and non-target bacteria and allows specific and accurate identification of the species of the tested bacteria isolates.

Bacteria ; classification ; isolation & purification ; China ; Food Contamination ; analysis ; Food Microbiology ; Oligonucleotide Array Sequence Analysis ; methods

China ; Consumer Product Safety ; standards ; Food Contamination ; prevention & control ; Food Inspection ; standards ; Food Microbiology ; Foodborne Diseases ; prevention & control ; Humans

OBJECTIVEThe loop-mediated isothermal amplification (LAMP) detection method was applied to detect Listeria monocytogenes in food. The specificity and sensitivity of this method were evaluated through comparing it with Real-time PCR and conventional detection method.

METHODSThe LAMP primers were designed based on hly gene of Listeria monocytogenes. The LAMP method was applied to detect 88 Listeria monocytogenes, 1 reference strain ATCC 15313 of Listeria monocytogenes and 33 non-targets bacteria strains; base-material addition test and practical food samples detection were also conducted. Both of Real-time PCR and ISO 11290-1 methods were used as parallel detection method in addition to LAMP. The three kinds of methods were compared by specificity, sensitivity, detection limit and the detection result of practical food samples.

RESULTSBoth detection results of LAMP and Real-time PCR for 89 Listeria monocytogenes were positive (100%, 89/89), 33 non-targets bacteria strains were negative (100%, 33/33). The sensitivity of LAMP was 2 × 10² CFU/ml, which was consistent with Real-time PCR method (2 × 10² CFU/ml) and better than ISO 11290-1 method (2 × 10² CFU/ml). Base-material addition test result showed that the detection limit of the three kinds of methods were 3 CFU/25 g samples. And the result of practical food samples displayed the same detection rate of 4% in the three methods (2/45).

CONCLUSIONThe LAMP method of Listeria monocytogenes established in this study has good specificity and sensitivity, which can be applied to the rapid detection of Listeria monocytogenes.

Food Contamination ; analysis ; Food Inspection ; methods ; Food Microbiology ; Listeria monocytogenes ; genetics ; isolation & purification ; Nucleic Acid Amplification Techniques ; methods

OBJECTIVE: To analyze the status quo of quantitative classification in Hunan Province catering industry, and to discuss the countermeasures in-depth. METHODS: According to relevant laws and regulations, and after referring to Daily supervision and quantitative scoring sheet and consulting experts, a checklist of key supervision indicators was made. The implementation of quantitative classification in 10 cities in Hunan Province was studied, and the status quo was analyzed. RESULTS: All the 390 catering units implemented quantitative classified management. The larger the catering enterprise, the higher level of quantitative classification. In addition to cafeterias, the smaller the catering units, the higher point of deduction, and snack bars and beverage stores were the highest. For those quantified and classified as C and D, the point of deduction was higher in the procurement and storage of raw materials, operation processing and other aspects. CONCLUSION The quantitative classification of Hunan Province has relatively wide coverage. There are hidden risks in food security in small catering units, snack bars, and beverage stores. The food hygienic condition of Hunan Province needs to be improved.
China ; Food Contamination ; prevention & control ; Food Microbiology ; Food Services ; organization & administration ; Foodborne Diseases ; prevention & control ; Hygiene ; Restaurants ; legislation & jurisprudence

A cross-sectional examination of 55 points of street foods in Thai Nguyen city was carried out, the results showed that 54.55% of samples of drinking water, 27.7% of samples of kitchen tools, 18.8% of samples taken from staffs hand and 52.73% of samples prepared foods were contaminated with microbiological agents (the main was E.coli) and did not meet hygienic national standards.
Food Contamination ; Food

OBJECTIVETo investigate the status of bacterial contamination in the shellfish products in Wenzhou.

METHODSOne hundred samples were collected and their bacterial populations including the total plate count were investigated.

RESULTSOf the 100 samples collected, 67 samples failed to not meet the national regulations due to bacterial contamination, accounting for 67% of the total samples. Among the contaminated samples, the most serious contamination was caused by coliforms (61.4% of the total plate count with contamination), followed by Salmonella (18.6%), Vibio parahaemolyticus (15.7%), Listeria spp. (4.3%) and others (6%).

CONCLUSIONMicrobial pollution has become a threat to the marine shellfish products in Wenzhou.

Animals ; China ; Colony Count, Microbial ; Food Contamination ; Food Microbiology ; Listeria ; isolation & purification ; Salmonella ; isolation & purification ; Shellfish ; microbiology

OBJECTIVETo realize the contamination of total aflatoxins in corn, peanut, rice, walnut and pine nut in China, and provide the base data for establishing a China tolerance limit standard and an international control practice for total aflatoxins.

METHODSThe samples of corn, peanut, rice, walnut and pine nut from Chongqing, Fujian, Guangdong, Guangxi, Hubei, Jiangsu, Shanghai and Zhejiang provinces and municipalities were collected randomly from markets, with the totally 284 samples. The samples were grounded and added to acetonitrile/water mixture. After filtering, the extract was transferred into a purifying column and pressed slowly. Then the purified liquid was derivatized with trifluoroacetic acid (TFA) and detected by using a high performance liquid chromatography (HPLC).

RESULTSThere was 70.27% corn having been detected out an average level of aflatoxins of 36.51 microg/kg and the highest level was 1098.36 microg/kg. At the same time, there was 14.86% corn exceeding the China national tolerance limit. In peanut, the aflatoxins detected rate was 24.24%. The average level was 80.27 microg/kg and the highest level was 437.09 microg/kg. While there was 3.03% peanut exceeding the China national and Codex tolerance limits. All of the rice, walnut and pine nut samples met the China tolerance limit for aflatoxins.

CONCLUSIONCorn and peanut might be the severely contaminated foods with aflatoxins in China. The aflatoxin B(1) in foods might be can not delegate the contamination of aflatoxins completely. Surveillance of total aflatoxins in foods suggested an actual need of establishing the China national and international standards for total aflatoxins.

Aflatoxins ; analysis ; Arachis ; China ; Chromatography, High Pressure Liquid ; Food Contamination ; analysis ; prevention & control ; Food Microbiology ; Nuts ; Oryza ; Zea mays