Carob samples from seven different Mediterranean countries (Cyprus, Greece, Italy, Spain, Turkey, Jordan and Palestine) were analyzed using Fourier Transform Infrared (FTIR) spectroscopy. Seed and flesh samples of indigenous and foreign cultivars, both authentic and commercial, were examined. The spectra were recorded in transmittance mode from KBr pellets. The data were compressed and further processed statistically using multivariate chemometric techniques, including Principal Component Analysis (PCA), Cluster Analysis (CA), Partial Least Squares (PLS) and Orthogonal Partial Least Square-Discriminant Analysis (OPLS-DA). Specifically, unsupervised PCA framed the importance of the variety of carobs, while supervised analysis highlighted the contribution of the geographical origin. Best classification models were achieved with PLS regression on first derivative spectra, giving an overall correct classification. Thus, the applied methodology enabled the differentiation of carobs flesh and seed per their origin. Our results appear to suggest that this method is a rapid and powerful tool for the successful discrimination of carobs origin and type.

Carobs unique compositional and biological synthesis enables their characterization as functional foods. In the present study, 76 samples derived from fruit and seeds of carobs, with origin from the countries of the Mediterranean region (Cyprus, Greece, Italy, Spain, Turkey, Jordan and Palestine) were analyzed for their nutritional composition, in order to identify potential markers for their provenance and address the carobs’ authenticity issue. Moisture, ash, fat, proteins, sugars (fructose, glucose, sucrose), dietary fibers and minerals (Ca, K, Mg, Na, P, Cu, Fe, Mn, Zn) were estimated following official methods. Due to the large number of data (76 samples × 17 parameters × 7 countries), chemometric techniques were employed to process them and extract conclusions. The samples of different geographical origin were discriminated with 79% success in total. The carobs from Cyprus, Italy and Spain were correctly classified without error. The main discriminators were found to be the dietary fibers, the carbohydrates and Cu, Zn and Mn, which emphasize their specific nutritional added value to the product and the country of origin impact. The results suggest that the proposed analytical approach is a powerful tool that enables the discrimination of carobs based on their country of origin. This research contributes to authenticity of carobs, adding value to local products.

Given the economic importance of potato production, establishing the origin of unknown commercial samples declared as local, is particularly important for both producers and competent authorities. In the study presented here, stable isotopic ratios of deuterium, oxygen, carbon and nitrogen, were determined in order to develop a potato provenance methodology. Isotopic determinations were conducted in an alcohol, preceded by the enzymatic degradation of potato starch using α-amylase to yield soluble dextrins and oligosaccharides. Subsequently, the hydrolyzed potato starch underwent fermentation to produce ethanol, which was then obtained through distillation under controlled conditions. The integration of data obtained from analyzing the D/H isotopic ratios using SNIF-NMR spectroscopy in potato samples for the first time, in conjunction with measurements of the ¹³C/¹²C, ¹⁵N/¹⁴N, and ¹⁸O/¹⁶O ratios via IRMS, yielded a unique isotopic fingerprint for the potato samples under examination. Elemental analysis by ICP-OES also added important information in the dataset. The chemometric analysis by applying OPLS-DA technique, highlighted the parameters of (D/H)_II, δ¹⁸O, R and Cu as the best discriminator markers. The proposed model gave 94.07% correct classification of the samples, regarding their geographical origin. It is believed that the differentiation of local potatoes is related to the unique geological and climatic conditions existing in the island. All the above-mentioned conclusions are very promising, for the protection of local potato production.