Wu J.,Ocean University of China |
Cao B.,Ocean University of China |
Li D.,Laboratory of Food Microbiology and Food Preservation |
Zhang Q.,Ocean University of China |
And 5 more authors.
Journal of Chinese Institute of Food Science and Technology | Year: 2016
Real-time quantitative PCR is a useful tool for foodborne virus detection, although false-positive results can be generated due to the high sensitivity of this method. In this study, a genetic sequence alignment method was adopted to verify the authenticity of qPCR positive results of Norovirus (NoV) GII.4 detected from shellfish samples., As a result, within the eight shellfish samples with high NoV contamination detected by RT-qPCR, two were confirmed as genuine positive, two might be NoV GII.4 variant strains, one was false positive contaminated by NoV GII.4 plasmids used as standard positive control in this study, and the other three were false positives caused by primer dimmers. This study suggests that genetic sequence alignment as an effective and feasible method of verifying the authenticity of qPCR positive results, will be worthy of further promotion. © 2016, Chinese Institute of Food Science and Technology. All right reserved. Source
Noseda B.,Laboratory of Food Microbiology and Food Preservation |
Ragaert P.,Laboratory of Food Microbiology and Food Preservation |
Pauwels D.,Laboratory of Food Microbiology and Food Preservation |
Anthierens T.,Laboratory of Food Microbiology and Food Preservation |
And 4 more authors.
Journal of Agricultural and Food Chemistry | Year: 2010
Selective ion flow tube mass spectrometry (SIFT-MS) is a direct mass spectrometric technique that allows qualitative and quantitative analysis of a large number of volatile organic compounds. Because of its speed and ease of use, this nondestructive technique could be considered as a practical tool for quality control. This research focuses on the possibilities of direct headspace sampling by SIFT-MS for the quantification of the volatile basic nitrogen content (TVB-N) of fish fillets. These volatile bases [trimethylamine (TMA), dimethylamine (DMA), and ammonia] give additional information in conjunction with the sensory scoring and microbiological analysis about the quality of the fish fillets. This research validates in a first part the SIFT-MS method for the quantification of the volatile bases in mixed cod samples. With regard to the investigated linearity, repeatability, reproducibility, recovery, limit of detection, and limit of quantification, SIFT-MS appeared to be an adequate technique for measuring volatile bases spiked on cod. In the second part of this research, the technique was validated for the analysis of volatile bases on cod fillets during a storage experiment under ice. A good correlation was obtained between the proposed direct headspace sampling and traditional methods. The sensitivity of the SIFT-MS method can be improved when cod fillets are made more alkaline (pH >11) during sampling. © 2010 American Chemical Society. Source