Determination of the inorganic elements in jujube fruits cultivated in different regions by microwave digestion and ICP- AES method

Inorganic elements in jujube fruits collected from different regions were determined by microwave digestion coupled with ICP- AES method.The results showed that in the 19 kinds of inorganic elements determined in the assay,almost all of the samples contained the elements of K,Ca,Mg,Na,Fe,B,Sr,Al,Zn,Mn,Mo and Cu.The harmful heavy metal element of Pb was detected in most of samples,and its average content was 2.62 μg / g.The harmful elements of As,Cd,Cr and Hg were not detected in all the samples.Based on the contents of elements in different samples,principal component analysis method was performed and 4 factors( F1~ F4) were selected to evaluate the jujube nutrition and health value. The evaluation function was F = 0.19936F1+ 0.18240F2+ 0.17396F3+0.10946F4. The results showed that the cultivars from Shaanxi Binxian,Henan Neihuang and Shandong Heze ranked in the top three in the terms of inorganic elements,which indicated that the qualities of above samples were better than those of other samples. This study provided the data of nutritional value and safety for the jujube resources,and also provided the reference for selecting the cultivation regions and cultivars of jujube.