Use of DNA Barcoding to Identify Species of Raw Ready‐To‐Eat Seafood Products Sold in Orange County, CA

Abstract

DNA barcoding is widely used to identify commercial fish species sold in the U.S and internationally. This method is based on DNA sequencing of a standardized region of DNA from a sample. Sequences can then be analyzed against the Barcode of Life Data system (BOLD) for species identification. Additional analysis of samples by a method called DNA mini‐barcoding can be used for samples that cannot be correctly identified to the species level by the traditional DNA barcoding method. While relatively high levels of seafood mislabeling have been reported for sushi dishes, few studies have investigated mislabeling of other raw, ready‐to‐eat (RTE) seafood such as poke and ceviche. The objective of this study was to evaluate the presence of species mislabeling in raw, RTE seafood products in Orange County, CA. DNA barcoding and mini‐barcoding were used to investigate 70 samples of sushi, ceviche, and poke collected from various locations in Orange County. All samples underwent DNA barcoding, followed by species identification using the BOLD database. Six samples underwent further analysis with mini‐barcoding. The FDA seafood list was used to identify common and acceptable market names. The results showed that 13 samples were substituted on the basis of species, and 20 samples did not have an acceptable market name. The overall mislabeling rate for all samples combined was 52.3% (33/63). These results indicate a need for greater scrutiny of labeling practices for raw, RTE seafood sold in Orange County, California.