Analysis of Tuna Species for Identification of Proper Labeling Practices in Tuna-Containing Products

Abstract

Numerous tuna-containing products were procured and tested via DNA isolation,
polymerase chain reaction, and gel electrophoresis respectively. This was done in order
to determine whether the labeled species of tuna is the species actually present in the
product. Included among these samples were raw tuna, canned tuna, and tuna from a
fast-food restaurant franchise for a total of five samples. These products were tested for
DNA pertaining to the following species of tuna: Bluefin, Yellowfin, Albacore, Bigeye,
and Skipjack. Our results yielded few conclusions as many of the products did not
produce legible banding patterns on agarose gels after electrophoresis. This was
probably due to metal contamination of the canned tuna samples. The fast-food tuna,
which also returned inconclusive banding patterns, was in turn tested for DNA
pertaining to livestock, including pig, cattle, goat, sheep, and chicken. All returned
inconclusive results. However, the two raw tuna samples were identified as Yellowfin
tuna and Ahi tuna (similar to Yellowfin and Bigeye tuna); both were labeled correctly.