Tracing Atlantic Salmon (Salmo salar) in Processed Fish Products Using the Novel Loop-Mediated Isothermal Amplification (LAMP) and PCR Assays

Due to the legislative shortcomings, Atlantic salmon often shares the common name of San Wen Yu (Chinese ideogram (sic)(sic)(sic)) with other salmonids in China, therefore concealing the differences with the rest salmonids in price, nutrition, and even food safety aspect, and also paving the way for species adulteration. To help prevent this episode, the present study aimed to develop novel loop-mediated isothermal amplification (LAMP) and PCR assays for rapid identification of Atlantic salmon in processed fish products. Primers (LAMP and PCR) specific for Atlantic salmon were designed and the specificity was successfully confirmed. The sensitivity of the PCR assay was about 10-fold higher than the LAMP assay. Direct detection of the LAMP-positive samples using SYBR green in daylight or under UV light was also validated, making the total analysis time of 80 min, far less than the PCR assay. Finally, the developed methods were successfully applied to commercially San Wen Yu products, and the presence of Atlantic salmon was highlighted in only six products.