Investigation of geographic origin, salinity and feed on stable isotope profile of Pacific white shrimp (Litopenaeus vannamei)

Increasing numbers of mislabelled seafood products in the globalized market underline the need for approaches to identify the origin of these products. Pacific white shrimp cultured in different salinities (Litopenaeus vannamei) from 16 locations in China and USA were collected and differentiated based on δ13C and δ15N values. The δ13C and δ15N values of 16 commercial feeds used in shrimp culture were measured and effects of feed on C and N stable isotope composition in shrimp were investigated. Carbon and nitrogen isotopic analysis of the shrimp did not provide means to discriminate farmed shrimp from China and USA. However, the shrimp cultured in water with high salinity were enriched in 13C compared to shrimp cultured in freshwater and this provided another basis for discrimination. The correlation between δ13C in feed and shrimp was not significant, while the δ15N in feed and shrimp showed a trend of positive correlation.