Chemometric techniques for tracing the origin of foodstuff

The increased information available to the consumers together with the competition following the institution of the Common Market (EU countries) has led safety, nutritional value, eating characteristics, ethical, environmental, economic and social aspects to be more and more important and essential topics for the food industry. In a single word, there is an increasing demand for “quality”, as a primary criterion to access the market. “Quality” is defined as “the totality of characteristics of an entity (product or service) that bear on its ability to satisfy stated and implicit needs”. It is at a glance apparent that such a generic definition results in the concept of quality encompassing a wide range of meanings. In fact, it not only refers to the characteristics or the performances of a product, but also to the consumer and to the whole manufacturing system: consumers are not merely demanding quality, they also want to know everything about the product in terms of its “life” and origin (raw materials, production methods, harvesting location). Accordingly, a particular aspect of quality which has been gathering more and more attention during the recent years is that of the typicalness of the product. In fact, it has been widely reported in the literature that the geographical and botanical origin of a vegetable foodstuff are important variables regulating the overall quality of the product. This issue has been recognized by the European Union which has been introducing since 1992 a series of norms aimed at protecting these high quality productive identities, by the introduction of the Denominations of Origin (Protected Denomination of Origin, PDO, and Protected Geographical Indication, PGI). The products which are labeled by this Denomination must be produced in a well defined geographic area and manufactured using only one or few specified botanical or animal varieties. Consequently, to prevent the frauds in these field, the quality control laboratories would need an analytical method to determine the origin of the sample. Unfortunately, even if a great host of instrumental analytical techniques are at present under investigation, no one of those can be listed whose results can be directly related to the origin of the samples. An alternative way to cope with this problem is to use mathematical and statistical methods (chemometrics) to process the results of a set of determination performed on the samples in order to obtain the desired classification. In this communication, the successful use of different chemometric pattern recognition methods for the discrimination of food products according to their origin will be discussed, based on several examples taken from the authors’ experience (e.g. oils, wines, honey, wheat, rice).