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Wine is a product reflecting the relationship between man and nature and it is produced by man after cultivating a certain grape variety under the ecological conditions of certain climate and soil through appropriate brewing techniques. Therefore, the quality and style of wine are determined by the geographical conditions, such as climate and soil, as well as the ways of cultivating, harvesting and brewing adopted by the local people. As this geographical characteristic of wine has a strong market potential, the main producers of the world, in recent years, have established their own identification systems to determine wine geographical origin or grape variety by adopting the samples of wine, grape berries, grape leaves and the local soil, according to the standards of polyphenols, aroma, mineral elements. However, this filed is still paid little attention to in our country. In the present research, mineral element profiles were studied and compared in wine grape leaves and berries from seven wine producing regions and six varieties, the objective of which is to reveal the impacts of the geographical origin and grape varieties on mineral element profiles. This work will offer some useful data for differentiating region and variety of wine.The methods for stimutaneous determination of 58 mineral elements in grape leaves and berries, respectively, were developed by using inductively coupled plasma mass spectrometry (ICP-MS) with electric heating board digestion. According to the recovery test, the validation test of shrub leaf and tea leaf,standants, the analyses of detection limits and relative standard deviation, the present method was thought to have such advantages as high accuracy; good precision. On this base, 58 mineral elements in 30 leaf samples and 26 berry samples, respectively, were investigated, and these samples were collected from six wine grape varieties of seven wine producing regions. These grape varieties included V.vinifera, Cabernet Sauvignon, Cabernet Gernischt, Chardonnay, Cabernet Franc, Merlot and Italian Riesling, and these wine regions were Changli, Hebei (HBCL); Huailai, Hebei (HBHL); Penglai, Shandong (SDPL); Qilian, Gansu (GSQL); Helanshan, Ningxia (NXHLS); Shihezhi,Xinjiang (XJSHZ) and Mile,Yunan (YNML). Cluster analysis and Principal component analysis were then adopted to find comparability and characteristics of mineral elements involving regions and varieties. The results were shown as follows:Fifty-eight mineral elements were detected in the grape leaves, including 3 major elements, 16 rare earth elements and 39 trace elements. Cluster analysis indicated that similar mineral element profiles were present in among HBHL, HBCL and SDPL as well as in among XJSHZ, NXHLS and GSQL, whereas YNML had distinctive mineral profile from the other regionsno similarity. This is thus thought it feasible to identification of wine regions according to mineral elements of grape leaves. Principal component analysis showed that the contents of the rare earth elements in leaves from HBCL were the highest in all the detected regions, and the contents of the rare earth elements of leaves from GSQL and XJSHZ were higher than those from HBHL and SDPL. Additionally, the grape leaves from XJSHZ had higher contents of Zr、Fe、V、Al、Nb than the leaves from SDPL and YNML. The content of Au in leaves from NXHLS was higher than that from XJSHZ, and the contents of Ba、Ga in leaves from YNML were higher than HBHL and SDPL.Fifty-eight mineral elements could be detected in the grape ripen berries too. Cluster analysis showed that the characteristics of mineral elements of grape ripe berries from HBHL, SDPL and YNML had a certain similarity, and the similar profilesof mineral elements in berries were present in NXHLS and GSQL, which indicated that it was feasible for identifying regions on the basis of mineral element profile of grape berries too. Principal component analysis revealed that the contents of the rare earth elements in grape berries from BHCL were the highest in all the detected regions, which was consistant to the results of grape leaves. The grape berries from GSQL and NXHLS contained higher levels of Li, Sr, Na and U than those from SDPL, HBHL and YNML, moreover, the contents of Mg and Ca in grape berries from NXHLS was higher than those from GSQL. Compared with those from SDPL, the berries from YNML and HBHL showed higher levels Mg and Ca.The characteristics of 58 mineral elements were analyzed in ripen berries and function leaves of six grape varieties from the same wine producing region or different regions. Both cluster analysis and principal component analysis on the basis of grape varieties showed that characteristics of mineral elements in the berries and the leaves were not grape variety-dependent, therefore it was difficult to identify grape varieties according to the composition and contents of mineral elements of grape leaves or gerries.In conclusion, the present study indiceted that the profiles of of mineral elements of wine grape leaves and berries were mainly affected by the region factors, other than by the variety factors. It is thus thought that mineral elements can be used for identification of producing regions of wine grapes, but not for identification of the grape varieties.
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