Stable Isotope Analysis for Tracing the Geographical Origin of Beef

Carbon, nitrogen, and oxygen stable isotope ratios of beef from Japan, the USA, Australia, and New Zealand were examined as potential tool for verifying the geographical origin of beef. Each element of the isotope ratios of beef reflects the environmental fattening condition (region and feed) rather than the breed. Beef from USA is characterized by a higher carbon isotope ratio than that from other countries. Also, beef from Australia is characterized by higher oxygen isotope ratio than that from other countries. Moreover, we determined the carbon, nitrogen and oxygen stable isotope ratios of beef from Okinawa, Mie, Yamagata, and Hokkaido. Carbon and nitrogen isotope ratios did not show much difference among the four regions. On the other hand, the oxygen isotope ratios were the highest in beef from Okinawa, which was the most southerly area among the four regions. Such ratios became lower as the latitude became higher. These results suggest that a comparison of carbon, nitrogen, and oxygen stable isotope ratios is applicable as a potential tool for the discrimination of beef between not only different countries but also different regions within Japan.