Metodi isotopici e modelli per la tracciabilit\ue0 dei prodotti animali

The main elemental constituents (H, C, N, O, S) of bio-organic material have different stable isotopes (2H, 1H; 13C,12C; 15N,14N; 18O,17O,16O; 36S, 34S, 33S, 32S). Isotopic ratios can be measured precisely and accurately using dedicated analytical techniques such as Isotope Ratio Mass Spectrometry (IRMS). Analysis of these ratios shows potential for assessing the authenticity of food of animal origin. Geographical, climatic, pedological, geological, botanical and agricultural factors affect the stable isotope ratios (SIR) of bio-elements and SIR variations are ultimately incorporated into animal tissue through eating, drinking, breathing and exchange with the environment, being memorised in the resulting foods. As a consequence, the stable isotope ratios analysis of H, C, N, O and S has shown high potential for determining geographical origin, animal diet and the production system (organic/conventional) for pork, beef and poultry, milk, butter, cheese, fish and shellfish. In the case of the hard PDO cheeses Grana Padano and Parmigiano Reggiano, it is also used in real-life situations to assess the authenticity of grated and shredded cheese on the market. With this work I tried to fill in some of the research gaps found reviewing the literature on the application of the analysis of the stable isotope ratios of bioelements (2H/1H, 13C/12C, 15N/14N, 18O/16O, 34S/32S), for the traceability of animal products, in particular meat, dairy and fish. In detail, the research aimed at: \u2022 studying the variation of stable isotope ratios in blood fractions of lamb following dietary changes, \u2022 detecting the efficacy of IRMS for tracing lamb production systems in four regions of the north west of Tunisia \u2022 investigating the ability of the isotopic analysis to discriminate and trace the geographical origin of rainbow trout, \u2022 validating through a collaborative study the methods for analysing the isotopic and mineral profile of cheese, \u2022 characterising the isotopic and mineral profile of Mozzarella di Bufala PDO cheese. We found that d13Cplasma, d18Oplasma and d34Splasma of lamb were different 7 days after an abrupt switch from a pasture- to a concentrate-based diet. d15Nplasma and the isotope ratios of blood erythrocytes were not different on the different sampling dates and were not affected by the change of diet over a 14 days period. Therefore the combination of isotopic ratios of plasma and erythrocytes represents a good tool for deducing the dietary background of lambs. Indeed, erythrocytes were shown to be suitable for verifying whether the animal was actually pasture-raised and could merit a higher price, while the analysis of plasma could detect very short finishing periods in previously grazed animals. The efficacy of IRMS for tracing lamb production system was investigated in four regions of the north west of Tunisia, characterized by herbaceous pasture. The isotopic profiles of the Tunisian lamb meat types provided useful signatures for a satisfactory traceability of the lamb meat samples produced in Tunisia (sensitivity = 1.00). However, the differences between them were not sufficient and systematic to be validated by an external set of samples including 10 Italian lamb types. For investigating the ability of the isotopic analysis to trace the geographical origin of fish, we measured the isotopic ratios of H, C, N, O and S in defatted fillet and the extracted lipid fraction from farmed rainbow trout reared in different Italian farms and with two types of feeds: high fish content (HF) and low fish content (LF) feeds. The aim was to investigate the ability of isotopic analysis to discriminate and trace the geographical origin of trout from two regions of northern Italy (Friuli Venezia Giulia and Trentino), also according to the type of feed. We found that the C, N and S isotope ratios of feed and fillet were highly positively correlated among and between each other, and negatively correlated with the d2H and d18O of feed\uf020and with the d2Hfat of fillet, which were in their turn highly interrelated. The d2H and d18O of fillet were interrelated and positively correlated with d18Owater. In comparison with other variables, the d18Ofat of fillet showed less significant correlation with the other isotopic parameters. Good discrimination was found between trouts according to the type of feed and with the origin. For validating the isotopic and elemental analytical methods, an international collaborative study based on blind duplicates of 7 hard cheeses was performed according to the IUPAC protocol and ISO Standards 5725/2004 and 13528/2005. The H, C, N and S stable isotope ratios of defatted cheese determined using IRMS and the content of Li, Na, Mn, Fe, Cu, Se, Rb, Sr, Mo, Ba, Re, Bi, U in cheese after acid microwave digestion using ICP-MS were analysed in 13 different laboratories. The average standard deviations of repeatability (sr) and reproducibility (sR) were defined for both the isotopic and the mineral variables. The validation data obtained here can be submitted to the standardisation agencies to obtain official recognition for the methods, which is fundamental when they are used in commercial disputes and legal debates. This is very important for PDO cheeses, such as the Parmigiano Reggiano and Grana Padano, which cost more than double the generic similar cheeses and must be protected against mislabelling. A first evaluation of the isotopic and mineral data measured in buffalo milk and corresponding Mozzarella di Bufala Campana PDO, highlights the importance of the d18O and d2H values of casein, as well as of the content in Rb for tracing the origin of these product

Using Bioelements Isotope Ratios and Fatty Acid Composition to Deduce Beef Origin and Zebu Feeding Regime in Cameroon

5openopenPerini, Matteo; Nfor, Mohamadou Bawe; Camin, Federica; Pianezze, Silvia; Piasentier, EdiPerini, Matteo; Nfor, Mohamadou Bawe; Camin, Federica; Pianezze, Silvia; Piasentier, Ed

Nuclear magnetic resonance spectroscopy in extra virgin olive oil authentication

Extra virgin olive oil (EVOO) is a high-quality product that has become one of the stars in the food fraud context in recent years. EVOO can encounter different types of fraud, from adulteration with cheaper oils to mislabeling, and for this reason, the assessment of its authenticity and traceability can be challenging. There are several officially recognized analytical methods for its authentication, but they are not able to unambiguously trace the geographical and botanical origin of EVOOs. The application of nuclear magnetic resonance (NMR) spectroscopy to EVOO is reviewed here as a reliable and rapid tool to verify different aspects of its adulteration, such as undeclared blends with cheaper oils and cultivar and geographical origin mislabeling. This technique makes it possible to use both targeted and untargeted approaches and to determine the olive oil metabolomic profile and the quantification of its constituent

A multi-methodological protocol to characterize PDO olive oils

An analytical approach including Panel Test, Isotope Ratio Mass Spectrometry (IRMS) and Nuclear Magnetic Resonance (NMR) spectroscopy was proposed to characterize Italian “Colline Pontine” PDO olive oils (40 samples) of two consecutive crop years. Our approach has evidenced the high quality of these olive oils. Only 6 of 40 olive oils samples were defined as “defective” by the official Panel Test due to the detection of negative sensory attributes. The low variability of isotopic data monitored by IRMS confirmed that the olive oil samples all came from a limited geographical area. NMR spectra did not evidence any chemical composition anomaly in the investigated samples. In order to assess the influence of harvesting year over the olive oil chemical composition, the NMR analysis was extended to other 22 olive oil samples of a third harvesting year. NMR data were submitted to two different statistical methods, namely, analysis of variance (ANOVA) and principal component analysis (PCA) allowing olive oils of three consecutive harvesting years to be grouped

Insights into the stable isotope ratio variability of hybrid grape varieties: a preliminary study

Background: Official stable isotope databases, based on the analysis of (D/H)I ethanol , (D/H)II ethanol , δ13 Cethanol and δ18 Owater of wine, are an indispensable tool for establishing the limits beyond which the mislabeling or the addition of sugar and/or water in wine production can be detected. The present study investigates, for the first time, whether the use of hybrid varieties instead of European Vitis vinifera for wine production can have an impact on the stable isotope ratios. Results: The analyses were performed by isotope ratio mass spectrometry and site-specific natural isotope fractionation by nuclear magnetic resonance, in accordance with the official methods of the International Organization of Grapes and Wine. The comparison shows the tendency of some stable isotope ratios of hybrid varieties, in particular (D/H)I , to deviate from the regional averages of the V. vinifera samples. Notably, Baron, Monarch and Regent showed significantly different values at one of the two sampling sites. Particularly high δ13 C values characterize Helios compared to other hybrid varieties. Conclusion: For the first time, and from an isotopic point of view, the present study investigates the wine obtained from hybrid varieties, showing that further attention should be paid to their interpretation, on the basis of the database established according to the European Regulation 2018/273. © 2022 Society of Chemical Industry

Application of 13C Quantitative NMR Spectroscopy to isotopic analyses for vanillin authentication source

6openInternationalBothThe carbon stable isotope ratio (δ13C) is a valuable chemical parameter in the investigation of the geographic origin, quality, and authenticity of foods. The aim of this study is the evaluation of the feasibility of 13C-NMR (Nuclear Magnetic Resonance) spectroscopy to determine the carbon stable isotope ratio, at natural abundance, of small organic molecules, such as vanillin, without the use of IRMS (Isotope Ratio Mass Spectrometry). The determination of vanillin origin is an active task of research, and differentiating between its natural and artificial forms is important to guarantee the quality of food products. To reach our goal, nine vanillin samples were analyzed using both 13C quantitative NMR spectroscopy (under optimized experimental conditions) and IRMS, and the obtained δ13C values were compared using statistical analysis (linear regression, Bland–Altman plot, and ANOVA (analysis of variance)). The results of our study show that 13C-NMR spectroscopy can be used as a valuable alternative methodology to determine the bulk carbon isotope ratio and to identify the origin of vanillin. This makes it attractive for the analysis in the same experiment of site-specific and total isotope effects for testing authenticity, quality, and typicality of food samples. Moreover, the improvement of NMR spectroscopy makes it possible to avoid the influence of additives on carbon stable isotope ratio analysis and to clearly identify fraud and falsification in commercial samplesopenPironti, C.; Ricciardi, M.; Motta, O.; Camin, F.; Bontempo, L.; Proto, A.Pironti, C.; Ricciardi, M.; Motta, O.; Camin, F.; Bontempo, L.; Proto, A

Isotopic characterization of Italian industrial hemp (Cannabis sativa L.) intended for food use: a first exploratory study

In this study, Italian industrial hemp (Cannabis sativa L.) intended for food use was isotopically characterized for the first time. The stable isotope ratios of five bioelements were analyzed in different parts of the plant (i.e., roots, stems, inflorescences, and seeds) sampled in eight different regions of Italy, and in five hemp seed oils. The values of δ2H, δ13C, δ18O, and δ34S differed according to the latitude and, therefore, to the geographical origin of the samples and the climate conditions of plant growth, while the δ15N values allowed us to distinguish between crops grown under conventional and organic fertilization. The findings from this preliminary study corroborate the reliability of using light stable isotope ratios to characterize hemp and its derived food products and contribute to the creation of a first isotopic database for this plant, paving the way for future studies on authentication, traceability, and verification of organic labelin

GC-C-IRMS on single fatty acids and EA-IRMS on bulk lipid to study the fractionation processes in bovine organism and to detect differences in four matrices of Simmental cows fed on C3 and C4 diets

Fatty acids (FAs), carboxylic acids with a long aliphatic chain, detectable in both adipose tissue and muscle of animals, strongly contribute to different aspects of meat quality and are central to the nutritional value of this product [1]. Focusing of bovine meat, we must consider that the FAs may derive either from the animal diet only, as is the case with essential linoleic and linolenic acid, or from de novo endogenous synthesis, or both [2]. As for the biosynthetic pathway the FAs follow in cow organism, dietary FAs undergo substantial transformations into the digestive tract before depositing into the tissues. First, the hydrolyzation of complex lipids deriving from the diet, carried out by bacteria and protozoa in the rumen, produces long chain fatty acids (LCFAs) and other organic compounds [3]. Then, the free FAs released during hydrolysis are converted to saturated ones, primarily stearic and secondarily palmitic acid through biohydrogenation [3]. On exiting the rumen, the FAs flow into the duodenum, where the absorption takes place. Furthermore, the FAs reach the liver carried by the blood, whose flow, together with the FAs concentration, influences their supply to this organ [5]. In this work, two groups of multiparous cull cows fed according to two different dietary regimes (based on products deriving from plants characterized by either C3 or C4 photosynthetic cycle) were considered. The different paths C3 and C4 plants follow for CO2 fixations result in discriminating carbon isotopic ratios (δ13C). Therefore, the ability to distinguish between animals directly comes from the isotopic differences in the feeding regimes. Different cow compartments (rumen, duodenum, liver and meat) led to the diet-based discrimination of the animals. The presented results were obtained by analysing the δ13C of both the bulk lipidic extract through EA-IRMS and six FAs through GC-IRMS in each compartment. Furthermore, it is worth considering that several chemical reactions resulting in isotopic fractionation take place in the bovine organism. On this basis, the compound-specific analysis of the fatty acids in the different compartments of all cows gave the opportunity to compare the fractionation processes taking place in the bovine organism and to highlight differences depending on the dietary regime of the cows, whether C3- or C4- base

Can we discover truffle’s true identity?

This study used elemental and stable isotope composition to characterize Slovenian truffles and used multi-variate statistical analysis to classify truffles according to species and geographical origin. Despite the fact that the Slovenian truffles shared some similar characteristics with the samples originating from other countries, differences in the element concentrations suggest that respective truffle species may respond selectively to nutrients from a certain soil type under environmental and soil conditions. Cross-validation resulted in a 77% correct classification rate for determining the geographical origin and a 74% correct classification rate to discriminate between species. The critical parameters for geographical origin discriminations were Sr, Ba, V, Pb, Ni, Cr, Ba/Ca and Sr/Ca ratios, while from stable isotopes δ18O and δ13C values are the most important. The key variables that distinguish T. magnatum from other species are the levels of V and Zn and δ15N values. Tuber aestivum can be separated based on the levels of Ni, Cr, Mn, Mg, As, and Cu. This preliminary study indicates the possibility to differentiate truffles according to their variety and geographical origin and suggests widening the scope to include stable strontium isotope