OBJECTIVETo explore the status of clenbuterol pollution in swine products in Beijing city in 2002.

METHODSEuropean Union method (EUR 15127-EN Cy2.3) was adopted to examine the samples. Samples were screened by enzyme-linked immunosorbent assay (ELISA) and confirmed by GC-MS. Detected limit of the method was 0.5 micro g/kg. Samples, including lung, liver, pork, kidney and urine of swine, were collected from slaughterhouses, refrigeratories and markets in 11 districts of Beijing.

RESULTSThe results indicated that 185 out of 1 379 samples were positive with an annual positive rate of 13.4%. The highest was 15.7% in lung of swine, followed by urine 15.2% and pork liver 14.0%.

CONCLUSIONRates of detection had decreased from 30.0% to 2.7% during 2002.

Animals ; China ; Clenbuterol ; analysis ; Drug Residues ; analysis ; Food Contamination ; analysis ; Humans ; Meat ; analysis ; Meat Products ; Swine

Adulteration in meat products is a widespread issue that could lead to serious threats to public health and religious violations. Technology that offers rapid, sensitive, accurate and reliable detection of meat species is the key to an effectual monitoring and control against meat adulteration. In recent years, high-throughput sequencing-based DNA metabarcoding technology has developed rapidly. With the characteristics of being high-throughput, highly precise and high-speed, this technology can simultaneously identify multiple species in complex samples, thus offering pronounced advantages in the surveillance of adulteration in meat and meat products. Starting with an introduction of the major developments in the high-throughput sequencing technology in the past two decades, this review provides an overview of the technical characteristics and research methods of DNA metabarcoding, summarizes the application of DNA metabarcoding technology in meat adulteration detection over the last few years, discusses the challenges of using DNA metabarcoding technology in the detection of meat adulteration, and provides future prospects on the development of this technology.
DNA ; Food Contamination/analysis* ; High-Throughput Nucleotide Sequencing/methods* ; Meat/analysis* ; Meat Products ; Technology

No abstract available.
Animals ; Cattle ; Encephalopathy, Bovine Spongiform/epidemiology ; Meat/*analysis ; United States

OBJECTIVETo investigate Benzo (a) pyrene (BaP) residue in retail food of Xiamen.

METHODSBaP residue in 121 retail food samples collected from Xiamen were determined by a rapid BaP detector based on derivative constant-energy synchronous fluorescence technique.

RESULTSBaP was detected in 84.3% samples and the concentration were ranged from 0.17 to 59.0 microg/kg. There were 49.6% samples exceeding 5.00 microg/kg, and most of them were roasting food (1.44 - 54.10 microg/kg), processed meat products (0.17 - 59.00 microg/kg) and aquatic products (2.79 - 36.80 microg/kg). The BaP concentration in 34 samples collected from roadside stands were 1.78 - 49.60 microg/kg, of which the rate of the samples exceeding 5.00 microg/kg was 88.2%.

CONCLUSIONThe BaP contamination in retail food samples from Xiamen is serious.

Benzo(a)pyrene ; analysis ; China ; Food Contamination ; analysis ; Food Inspection ; methods ; Meat Products ; analysis

Animals ; Antibodies ; immunology ; Cattle ; Enzyme-Linked Immunosorbent Assay ; Immunoassay ; methods ; Meat Products ; analysis ; Testosterone ; analysis

Neuropeptide Y (NPY) is one of the most important orexigenic agents in central regulation of feeding behavior, body weight and energy homeostasis in domestic chickens. To examine differences in the hypothalamic NPY between layer-type and meat-type of chickens, which are two divergent kinds of the domestic chickens in feeding behavior and body weight, we detected mRNA levels of NPY in hypothalamic infundibular nucleus (IN), paraventricular nucleus (PVN) and lateral hypothalamic area (LHA) of these two types of chickens using one-step real time RT-PCR. The meat-type chicken had more food daily (about 1.7 folds) and greater body weights (about 1.5 folds) and brain weights than the layer-type chicken at the age of 14 d. In the meat-type of chicken, NPY mRNA levels of the IN and PVN were significantly greater than those of the LHA, and were not significantly different between the IN and PVN. However, in the layer-type of chicken, NPY mRNA levels were significantly greater in the IN than those in the LHA and PVN, and were not significantly different between the PVN and LHA. In all these hypothalamic regions, the layer-type of chicken had significantly higher NPY mRNA levels than the meat-type chicken did. These results suggest the expression of NPY in the hypothalamus has a type-dependent pattern in domestic chickens.
Animals ; Body Weight ; Chickens ; classification ; metabolism ; Hypothalamus ; metabolism ; Male ; Meat ; Neuropeptide Y ; genetics ; RNA, Messenger ; analysis

AIMTo detect the residual clenbuterol in pork meat and liver using HPLC with Coulometric electrode array system.

METHODSHomogenized meat or liver sample was treated with 1 mol x L(-1) hydrochloric acid and centrifuged, the fat existing in meat or liver tissue was removed by diethyl ether. The pH of the remaining aqueous layer was adjusted to 10.8 +/- 0.2 or 11.6 +/- 0.2 for meat or liver and liquid-liquid extraction with diethyl ether was followed. The ether extract was evaporated to dryness, the residue was dissolved in the mobile phase. The mobile phase A consisted of 50 mmol x L(-1) phosphoric acid-30 mmol x L(-1) triethylamine and was adjusted to pH 4.0 with 2 mol x L(-1) sodium hydroxide solution. The mobile phase B consisted of methanol-acetonitrile (30:45). A mixture of mobile phase A and B (80:20) was used in the method. A four electrode array module was selected for quantitation, the electrode potentials were set at 450, 600, 650 and 680 mV respectively.

RESULTSThe two calibration curves for meat and liver showed good linearity between 1.88 - 60.16 ng x g(-1), the detection limit of clenbuterol was 1.2 ng x g(-1).

CONCLUSIONThis method using HPLC-electrochemical detection is reproducible, and the sensitivity is good enough for the determination of clenbuterol in meat and liver.

Animal Feed ; analysis ; Animals ; Chromatography, High Pressure Liquid ; methods ; Clenbuterol ; analysis ; Drug Residues ; analysis ; Electrochemistry ; methods ; Electrodes ; Liver ; chemistry ; Meat ; analysis ; Swine

BACKGROUND: With increasing media coverage of food safety incidents, such as that of clenbuterol residues in pork, food safety has become a major public health concern in China. Rapidly developing online markets attract increasing numbers of Chinese consumers to purchase food on the Internet. However, the quality and safety of food sold online are uncertain and are less reported on. OBJECTIVE: This research aimed to systematically study the quality and safety of chilled pork from wet markets, supermarkets, and online markets in China. RESULTS: The chilled pork samples from online markets were fresher than those from wet markets and supermarkets based on the surface redness (a* value). Chilled pork contained high levels of nutritional elements, especially the magnesium and phosphorus levels in samples from online markets. The levels of heavy metal element residues and veterinary drug residues in all chilled pork samples were within the standards limits. In addition, huge differences existed in the quality and freshness of the chilled pork samples from online markets according to principal component analysis (PCA). CONCLUSIONS Most chilled pork sold in Chinese markets was qualified and safe. It is necessary to establish an effective online market supervision system for chilled pork.
Animals ; China ; Cold Temperature ; Drug Residues/analysis* ; Food Preservation/standards* ; Food Quality ; Food Safety ; Metals, Heavy/analysis* ; Principal Component Analysis ; Red Meat/standards* ; Sus scrofa ; Veterinary Drugs/analysis*

OBJECTIVETo study influencing factors of detection of bovine central nervous system (CNS) tissue contaminated beef by enzyme immunoassay (EIA), and the method was applied to the detection of imported beef and domestic beef of China.

METHODSRaw beef homogenates containing different concentrations of raw CNS tissue and the same samples which were heated were detected after different time by RIDASCREEN(r) Risk Material 10/5 and RIDASCREEN(r) Probennahme- zubehor Sampling tools kits. PBS suspension and sample dilution buffer (SDB) suspension of bovine brain tissue with the same concentration of the standard were detected. Beef from USA and domestic market of China were then detected by the kits.

RESULTSThe kits could detect both raw and heated CNS tissue in the products with high sensitivity. The absorbance values (AV) increased with the concentrations of CNS in samples. Heating and increasing of time could decrease the absorbance values of the samples which contain CNS tissue. The AV of the PBS suspension of bovine brain tissue was higher than the SDB suspension and the AV of both were higher than the AV of standard of the same concentration. No CNS tissue was detected from all imported beef. No CNS tissue was detected in all samples from domestic market of China except for foxtail.

CONCLUSIONThe EIA method has high sensitivity for detection of bovine CNS tissue contaminated beef with the glial fibrillary acidic protein (GFAP) as accurate target substance. Heating and increasing of time can lead to decreasing of the AV of samples. Improper slaughter process can lead to contamination of bovine products by bovine CNS tissue.

Animals ; Brain ; metabolism ; Brain Chemistry ; Cattle ; Food Contamination ; analysis ; Food Inspection ; methods ; Glial Fibrillary Acidic Protein ; analysis ; Immunoenzyme Techniques ; Meat Products ; analysis

We carried out experiments with B-scan technology, computer image processing technology and statistical analysis, to extract feature parameters from histogram of different organizations in order to establish prediction methods of the meat quality of pigs. We then Explored and solved the assessment problems of intramuscular fat (IMF) content, to provide reference standards of using ultrasound for the classification of pork.
Adipose Tissue ; diagnostic imaging ; Animals ; Meat ; analysis ; standards ; Muscle, Skeletal ; chemistry ; diagnostic imaging ; Quality Control ; Swine ; Ultrasonography