This paper details with the preparation of new Multipurpose-Reference Materials (RMs) of rice grains and rice flour performed as a pilot study within the PRO-METROFOOD-RI project. RMs will be characterized for different parameters including contaminants, biomarkers, stable isotopes and markers of origin/authenticity. These RMs will also have a major role in quality control and quality assurance of other food products.

The purpose of this communication is to present the contribution of EXHM/GCSL-EIM in two different approaches used to assess interlaboratory measurements at different metrological levels. In the first one, at the high metrological order - CCQM level, concerning the key comparison “CCQM K138 - determination of aflatoxins in dried figs”, the method developed and the results reported by our institute are described. According to the second approach, participation in a Proficiency Testing scheme, the organization and evaluation of SCHEMA PTs reported results, are also introduced. Different methods for the determination of the assigned value, its uncertainty and the statistical evaluation of the SCHEMA 63 0X PTs series are demonstrated as well.

METROFOOD-RI is a research infrastructure to promote data and information on metrology in food and nutrition and is composed by a Physical infrastructure (P-RI) and an electronic infrastructure (e-RI). Concepts and the development of a pilot e-RI is presented in this work where several datasets from different countries are used and interrelated to integrate national e-resources into a European-wide e-RI providing new functionalities. The general functionalities will be described together with the challenges to combine already existing resources. Issues of the outcome will be discussed together with possible solution for the future.

Saffron, the spice produced from the red stigmas of the flower of Crocus sativus L. is a frequent target of fraud and mislabeling practices that cannot be fully traced using the ISO 3632 trade standard specifications and test methods. A molecular approach is proposed herein as an alternative, promising branding strategy for the authentication of highly esteemed saffron brands like the Greek Protected Designation of Origin (PDO) “Krokos Kozanis”. Specific ISSR markers were used to assess, the within species variability of several populations of C. sativus L. from the cultivation area of “Krokos Kozanis” and the potential differences with the band pattern produced by other Crocus species. Then, species-specific markers were developed suitable for HRM analysis coupled with universal DNA barcoding regions (trnL) (Bar-HRM) and applied to saffron admixtures with some of the most common plant adulterants (Calendula officinalis, Cartrhamus tinctorius, Gardenia jasminoides, Zea mays and Curcuma longa). The sensitivity of the procedure was tested for turmeric as a case study whereas HPLC-fluorescence determination of secondary metabolites was also employed for comparison. The overall results indicated that the Bar-HRM approach is quite effective in terms of specificity and sensitivity. Its effectiveness regarding the detection of turmeric was comparable to that of a conventional HPLC-based method (0.5 % vs 1%, w/w). Yet, the proposed DNA-based method is faster, cost-effective and can be used even by non-geneticists, in any laboratory having access to an HRM- capable real-time PCR machine. It can be thus regarded as a strong analytical tool in saffron authentication studies.

In the recent years, Raman spectroscopy was attested as a good candidate for food analysis. It is a rapid, simple and non-destructive technique which provides highly selective detection due to the specific Raman fingerprint of molecules. The sensitivity of Raman technique can be increased of several orders of magnitude exploiting the Surface Enhanced Raman Scattering effect. In general, SERS is obtained when molecules are absorbed onto, or microscopically close to, a suitable plasmonically active surface, such as roughened nanostructured metal surface, or metal colloids. Nevertheless, standardized methods of production and application of SERS systems are still needed. A good compromise between sensitivity and reproducibility of analysis is necessary to provide metrological analytical methods in the detection of food contaminants. The scope of this work is to compare different nanostructured systems to provide a reproducible Surface Enhanced Raman Scattering effect. Several innovative approaches were tested using different probe molecules, such as melamine and cumarin, which were selected as representative test materials for a wide class of food contaminants. SERS active surfaces ranging from solid substrates, such as flexible metal coated silicon nanopillars, and liquid suspensions of metal colloids, such as spheroidal nanoparticles and nanostars, were fabricated and tested in order to compare their efficiency in the detection of the above cited contaminants. The reproducibility of both strategies is also evaluated to investigate their applicability in the development of quantitative or screening methodologies.