Discrimination and quantification of adulterated edible bird's nest based on their improved cohesion stable isotope ratios

Abstract

Focusing on the high dispersion of stable isotope ratios (δ13C, δ15N, δ18O, δ2H) in edible bird's nest (EBN), a robust method was developed to simultaneously discriminate and quantify three types of substances (sialic acid, egg white and food gums) added separately into EBN. Results showed that by establishing a data processing formula to improve cohesion of the samples' isotope ratios, a discriminant formula was achieved with an accuracy ranging from 88% to 99%. With the three adulterated references, discriminant was set up by the calculated Euclidean distance with prediction accuracy ranged from 95.80% to 99.97%. Additionally, three equations were building-up to quantity the content of those adulterated substances of EBN, with satisfactory relative standard deviations and within the range from 1.34% to 6.31% (n = 6). By applying the developed methods, two out of the twelve samples were found to adulterate 3.9% sialic acid and 2.9% egg white respectively.