Element analysis of House- and Cave-EBN (edible bird's nest) traceability by inductively coupled plasma-mass spectrometry (ICP-MS) integrated with chemo-metrics

Edible bird's nest (EBN) is a high-value health-promoting tonic from swiftlets. However, cheap House-EBN is usually masqueraded as expensive Cave-EBN for profiteering. Efficient scientific means are required to trace Cave-EBN. After microwave digestion of EBN lyophilizing powder, its mineral element compositions were examined by using inductively coupled plasma-mass spectrometry (ICP-MS). Influences of two key factors, production environment and country, on the distribution of 21 elements were analyzed. Linear Discriminant Analysis (LDA) coupled with leave-one out cross validation was applied for modeling. Classifier generalization performance was assessed by the Confusion Matrix approach. ICP-MS identified the presence of 21 macro and micro elements with contributions of 99.65% and 0.35%, respectively. A two-way ANOVA established that B, Na, K, Ca, Mn, Cu, Sr, and Cd were the production-environment-specific elements. Among four different combinations based on three potential variables (Ca, Na, and Sr), Na/Ca was identified as the best among them having 100% specificity on tracing Cave-EBN. In conclusion, EBN was a good mineral element source. The methodology of integration of ICP-MS with chemo-metrics proved to be a powerful tool for tracing Cave-EBN.