Abstract:

This study aimed to confirm the possible traceability of yak meat samples from different regions using stable
isotopes. The δ13C, δ15N, and δ2H values of yak meat samples (muscle crude fat and de-fatted muscle) from Henan county
and Datong county of Qinghai province, and Hongyuan county and Jiulong county of Sichuan province were tested using
isotope ratio mass spectrometry (IRMS). The composition characteristics of δ13C, δ15N, and δ2H of yak meat samples were
compared and analyzed. The results demonstrated that the δ13C, δ15N, and δ2H differed significantly among meat samples
from different yak tissues (P < 0.05 or P < 0.01). The distinguishing capacity for de-fatted muscle was better than for muscle
crude. When the indicators of stable isotope were taken into comprehensive consideration, yak meat samples from different
places was better distinguished as compared to the individual indicators, and the combined analysis of stable nitrogen and
hydrogen isotopes provided potential indicators for tracing the origin of yak meat samples with an accuracy up to 85%. It is
a promising approach to classify yak meat based on δ13C, δ15N and δ2H combined with multivariate statistical methods.

Key words: yak, traceability, stable isotope, δ13C, δ15N, δ2H