Departamento Quı́mica Analı́tica, Nutrición y Bromatologı́a, Facultad de Ciencias, Universidad de Santiago de Compostela, Alfonso X el Sabio s/n, 27002 Lugo, Spain.
J Agric Food Chem. 2013 Sep 4;61(35):8444-51. doi: 10.1021/jf402001s. Epub 2013 Aug 21.
Potatoes from Galicia (northwestern Spain) are subjected to a Protected Geographic Indication (PGI) according to European legislation. Ten trace elements (Li, Na, K, Rb, Ca, Fe, Mg, Mn, Cu, and Zn) have been determined by atomic spectrometry in two sets of potato samples: Geo-Origin.set and Variety.set. The first data set is composed of samples of the only variety authorized by PGI (Kennebec) with two geographical origins: Galician and non-Galician. The second set corresponds to samples from different varieties but with only Galician geographical origin. Chemometric pattern recognition techniques have been applied to the study of potato geographical and varietal origins in relation to their capability for translocating metals from soil to tuber. Also, authentication models for classifying potato samples with Galician PGI based on metal fingerprints have been developed. The results obtained showed that samples of the same variety, Kennebec, have different metal fingerprints when they have been produced in different geographic locations. Also, diverse potato varieties cultivated on equal geographic Galician origin presented different metal profiles as well. Therefore, it can be concluded that classification studies on the differentiation of geographical origin of foods should take into account information of production area together with varietal data. Otherwise, classification obtained on the basis of the geographical origin could be due to the different variety or vice versa. Finally, two models were constructed for Kennebec Galician samples against Kennebec from other origins as well as against other varieties cultivated in Galicia (Liseta and Baraka). Both models achieved adequate classification rates (93-100%), good sensitivities, and total specificities (100%), allowing the fraud detection in the PGI label.
来自西班牙西北部加利西亚（Galicia）的土豆根据欧洲法规受到地理标志保护（PGI）。通过原子光谱法，在两组土豆样本中测定了十种微量元素（Li、Na、K、Rb、Ca、Fe、Mg、Mn、Cu 和 Zn）：Geo-Origin.set 和 Variety.set。第一个数据集由 PGI 授权的唯一品种（肯纳贝克）的样本组成，有两个地理来源：加利西亚和非加利西亚。第二个数据集对应于不同品种但只有加利西亚地理来源的样本。化学计量模式识别技术已应用于研究土豆的地理和品种起源与其从土壤向块茎转运金属的能力之间的关系。此外，还开发了基于金属指纹的基于 PGI 的加利西亚土豆样品分类鉴定模型。结果表明，同一品种（肯纳贝克）的样本在不同地理位置生产时具有不同的金属指纹。此外，在相同的加利西亚地理起源上种植的不同土豆品种也表现出不同的金属分布。因此，可以得出结论，关于食品地理起源差异的分类研究应考虑到生产区域的信息以及品种数据。否则，基于地理起源的分类可能是由于不同的品种或反之亦然。最后，针对加利西亚的肯纳贝克样本以及来自其他起源的肯纳贝克和在加利西亚种植的其他品种（Liseta 和 Baraka）构建了两个模型。两个模型都实现了较高的分类率（93-100%）、良好的灵敏度和总特异性（100%），允许在 PGI 标签中检测欺诈行为。
