Study on identification of red jujube origin by multi-element analysis

In order to explore the feasibility of mineral element analysis on the origin of red jujube, and to screen the effective indicators to distinguish the origin of red jujube, 34 samples of red jujube were collected from Xinjiang, Hebei, Shanxi and Gansu provinces of China. The contents of Na, Mg, K, Ca, P, B, Al, Ti, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Sr, Mo, Ba, Tl, Ge, Zr, Li, Rb, Cs, La, Ce and Nd in the samples of red jujube were determined by inductively coupled plasma mass spectrometer and analyzed by variance analysis, principal component analysis (PCA), clustering analysis (CA) and discriminant analysis (DA). The results demonstrated that the content of mineral elements in red jujube from different regions has its own characteristics. The average contents of Na and Ge in red jujube were the highest from Xinjiang province, while the average contents of Co, Cu, Zn, Se, Ba and Cs were the lowest. The average contents of Ca, Ba and Ti in red jujube in Hebei province were the highest, the average contents of K, Mn and Rb in red jujube in Shanxi province were the highest, and the average contents of Mg, P, Al, B, Ti, Fe and Cu in Gansu province were the highest. The content of Na in Xinjiang province was three times more than that of Gansu province, and the content of Rb in Hebei province was four times more than that of Xinjiang province. PCA explained 82.1% of total variation, indicating that it played a vital role in the classification of mineral elements of red jujube. Red jujube was divided into five groups at a cluster distance of 9.0, indicating that clustering analysis has achieved ideal results in the origin traceability of red jujube. By discriminant analysis, the correct discriminant rate of 100% was established for samples from Xinjiang, Hebei, Shanxi and Gansu provinces. Facts have proved that it is feasible to judge the traceability of the origin of red jujube by using multi-element analysis.