Food forensics

The food market nowadays accounts for huge incomes and therefore it is an easy target for falsification. This recalls the urgency for reliable and powerful diagnostic techniques, in order to develop analytical protocols for identification of frauds. MS-based strategies of analysis are definitely suitable for this task and have become in the last years of paramount importance in the field of food forensics. Sophisticated techniques have been developed that request short times of analysis and allow the identification of specific parameters, useful as classification markers. The wide range of techniques available [i.e. isotopic analysis, inductively coupled plasma - mass spectrometry (ICP-MS), hyphenated systems, stand-alone systems] allow to address a wide range of analytical questions pertaining to food authentication and traceability

Novel biological, forensic, and historical applications of inductively coupled plasma-mass spectrometry

This dissertation describes three new applications of inductively coupled plasma mass spectrometry (ICP-MS). Arsenic content was measured in rice and coffee samples. These results for the concentration of arsenic in rice and coffee independently verify the results of a similar FDA study. Direct comparisons of the arsenic content in different types of rice (i.e. black, brown, jasmine) indicated no correlation in the amount of arsenic and the type of rice. Additionally, the rice and coffee samples were cultivated in different locations throughout the world and results were analyzed to discern any trends between the amount of arsenic and the country of origin. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is used to measure the trace elemental composition of various well-known brands of duct and electrical tapes. A new method derived from existing chemometric principles (principal components analysis) for identifying which elements vary the most between the brands of tape is described. The new method is applied to measurements collected from duct and electrical tapes and they are compared to one another. Pigments from a ship which sank off the coast of Texas in 1684 were recently recovered. ICP-MS was used to perform elemental analysis on these samples to identify the type of pigment. These pigments were suspected to be products for trade with natives in the new world. As was common at the time, the pigments were also suspected of adulteration (being cut with a cheaper product); they were analyzed for evidence of such a practice. ICP-MS is one of the most sensitive useful tools for elemental analysis. Knowing the exact composition of various samples using this technique can help scientists assist in setting new public safety standards in the present, provide new techniques for the future, and learn about life in the past. The three applications highlight the versatility of ICP-MS to a broadening number of different scientific disciplines

Geochemical and spectroscopic fingerprinting for authentication and geographical traceability of high-quality lemon fruits.

Geochemical (mineral element and Sr isotope ratio) and spectroscopical fingerprinting (Near Infrared Spectroscopy) were proposed to authenticate and track the two high-quality lemon fruits from the Campania region (Limone di Sorrento PGI and Limone Costa d'Amalfi PGI) to protect them from frauds. Considering the geochemical indicators, we built different chemometric discriminant models based on mineral profile and 87Sr/86Sr isotope ratio. These two techniques were applied to discriminate fruits from different territorial scales, small territorial scales (region scale), and large territorial scales. The results of different discriminant models applied on mineral profiles of lemon juices, both on a small and large territorially scale, showed good discrimination according to provenance, especially for non-essential elements as Rb, Ba, Sr, Ti, and Co. These same elements have shown a good correlation with cultivation soils and stability between the two production years. It is worth noting that although, the performance of the whole elemental profile gave a better result than the profile of the non-essential elements, the reliability of the two models, calculated as the ratio between the percentage of correctly validated and classification samples, was similar. In addition, the Sr isotope ratio had shown a clear differentiation among the fruits from the Campania region and extra-regional samples, and by analysis of 86Sr/87Sr of soils, it was clear that the strontium isotope ratio of lemon juices was closely related to that of the bioavailable fractions of the soil. Furthermore, combining both isotopic and mineral profiles in lemon juices by a low-level data fusion approach, the results showed a better clustering according to geographical origins than the two-determination taken separately, although on an explorative level. In addition, the spectroscopical data (NIR) on intact lemon fruits showed the strong influence of environmental growing conditions on the samples. For this, the application of Linear Discriminant Analysis (LDA) models suggested building the discrimination models according to origins (PGI and not PGI productions) based on one production year. In the same way, the application of MLR models, that showed a strong relationship between quality properties of lemon fruits and NIR spectra, suggested the applicability of this technique to build predictive models for the quality properties. In addition, on a part of the total samples collected only in 2019 (intact lemons and juices), have been successfully applied two different chemometrics models i.e., LDA and Partial Least Square Discriminant Analysis (PLS-DA). The results showed better provenance discrimination using the lemon juices than the intact lemons. Comparing the results obtained, of the two approaches used, the results of geochemical fingerprinting have shown more stability for discriminate lemon fruits derived from two different production years, especially for not essential elements. However, considering the various vantages of the application of NIR spectroscopy (non-destructive, rapid, and cheap) and the results obtained, this technique can be used for rapid screening of samples in order to verify the quality and origins of lemon fruits during the year. The study of the pedoclimatic features was fundamental to understand the nature of discriminating variables, in both approaches. Additional research should be conducted to include a greater number of lemon farms (or sampling points) in the PGI area and to enlarge the existing database including lemon samples from other regions and validate the models built. These discriminant models based on geochemical and spectroscopical profiles of lemon fruits could substantially contribute to implementing a blockchain system for Campanian lemon traceability, providing real-time information not only to the final consumers but also to manufacturers, distributors, and retailers

Recent developments and trends in the application of strontium and its isotopes in biological related fields

Strontium is a chemical element without biological functions in humans. In fact, only two biological roles are known, both as a biomineral constituent. However, strontium and calcium (a significant biometal) present chemical similarities; hence, the absorption of the former by living organisms is plausible. Based on the particular properties of isotopes of strontium several applications of this chemical element in biological sciences have been developed. These include its radioactive and non-radioactive isotopes in medical applications or resorting to its stable isotopes as analytical tools in isotope fingerprinting (87Sr/86Sr) to study dietary habits and migration patterns of ancient populations, food authentication and forensic sciences. This article, reviews papers published between 2012 and 2016, highlights the use of strontium isotope ratios for such biological related applications and compiles an analytical database, providing a valuable tool for future studies in the area.This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement Nº 739568. JALS is indebted to Fundação para a Ciência e a Tecnologia (FCT), Portugal, for financial support (project UID/QUI/00100/2013).info:eu-repo/semantics/publishedVersio

Applying biogeochemistry to identify the geographic origins of insects - a model using prostephanus truncatus

"The application of geochemical screening for tracking insects and other organisms is poorly understood. We explored multi-elemental profiles of an insect pest and its food from different locations in order to identify intrinsic markers of geographic origin. ICP-AES screening was completed for soil, maize grains and Prostephanus truncatus of different geographic origin, with insects collected in the field or reared on maize under controlled conditions. Background level geochemical data are presented with concentrations of Cu, S and Sr in maize, and Al, Ba, Ca, Fe, S, Si, Sr, Ti and Zn in insects differing according to their origin, or that of their food. Cu, Fe and Zn determinations of insects were 20, 6.5 and 11.5 times the concentrations of the maize they were reared on. A Linear Discriminant Analysis (LDA) based on Al, Fe, Sr and Zn successfully assigned 78% of laboratory-reared P. truncatus and 94% of field-caught insects to their origin (68% and 75% respectively after jacknifing). There was excellent discrimination between insects reared on maize from Guanajuato and Nuevo Léon, and Guanajuato and Michoacán, good separation between Sonora and Nuevo Léon but overlap for Sonora, Guanajuato and Michoacán, and Michoacán and Nuevo Léon. The same LDA for field-caught insects gave complete separation between Michoacán and Sonora, but some overlap between Michoacán and Nuevo Léon. This robust ICP-AES technique successfully identified a combination of elements able to classify insects according to their origin. The model was restricted to elements showing a normal distribution but non-parametric tests suggest other elements may act as intrinsic markers. This shows the potential of atomic spectroscopy for remotely tracing insects and other biological materials, with applications including providing provenance data for species routinely captured for surveillance and to track natural enemies and wildlife.

Inorganic arsenic determination in food: a review of analytical proposals and quality assessment over the last six years

Here we review recent developments in analytical proposals for the assessment of inorganic arsenic (iAs) content in food products. Interest in the determination of iAs in products for human consumption such as food commodities, wine, and seaweed among others is fueled by the wide recognition of its toxic effects on humans, even at low concentrations. Currently, the need for robust and reliable analytical methods is recognized by various international safety and health agencies, and by organizations in charge of establishing acceptable tolerance levels of iAs in food. This review summarizes the state of the art of analytical methods while highlighting tools for the assessment of quality assessment of the results, such as the production and evaluation of certified reference materials (CRMs) and the availability of specific proficiency testing (PT) programmes. Because the number of studies dedicated to the subject of this review has increased considerably over recent years, the sources consulted and cited here are limited to those from 2010 to the end of 2015

Diskriminasi Produk Berindikasi Geografis dari Daerah Istimewa Yogyakarta menggunakan Kandungan Mineral

AbtrakPenelitian ini bertujuan membedakan produk-produk berindikasi geografis dari Daerah Istimewa Yogyakarta menggunakan kandungan mineralnya. Kandungan dari empat elemen, yaitu Cu, Fe, Mn dan Zn, pada sampel salak pondoh dan nira kelapa yang merupakan produk berindikasi geografis dari Daerah Istimewa Yogyakarta diukur menggunakan Atomic Absorption Spectrometry (AAS). Data yang diperoleh kemudian diolah menggunakan diagram pencar dan analisis diskriminan. Penggunaan diagram pencar elemen Fe dan Mn mampu memisahkan sampel salak pondoh Sleman dengan sampel dari daerah lain, sementara penggunaan Canonical Discriminant Analysis mampu memisahkan sampel nira kelapa Kulonprogo dari daerah lain dengan tingkat ketepatan prediksi mencapai lebih dari 80%.Kata kunci: indikasi geografis, nira kelapa, salak pondoh, Yogyakarta AbstractThis study aims to discriminate Yogyakarta’s geographical indication products using their mineral contents. Mineral content of four elements, Cu, Fe, Mn, and Zn, in pondoh snake fruit and coconut sap which are geographical indication products from Yogyakarta Special Region (DIY) were measured by Atomic Absorption Spectrometry (AAS). The collected data were then analyzed with scatter and discriminant analysis. Scatter diagram of Fe and Mn was able to discriminate Sleman’s Pondoh snake fruits from other regions while Canonical Discriminant Analysis was able to separate Kulonprogo’s coconut sap samples from the other investigated regions with accurate prediction rate more than 80%.Keywords: coconut sap, geographical indication, pondoh snake fruit, Yogyakart

Assessment of accumulation of selected metals by native plants growing in polluted peruvian post-mining areas

Metal mining is one of the economic pillars of the Peruvian economy. Peru is the main producer of gold, zinc, lead, and tin in Latin America and the second largest producer of copper, silver, and zinc worldwide. Despite its economic importance, mining has also left a plethora of Mining Environmental Liabilities (MEL) whose inadequate waste management represents a risk for both the environment and human health and is a common trigger of social problems. The Cajamarca región is the second región in Peru in terms of the number of MEL sites with the majority of them located in the Hualgayoc district. The goal of the PhD project is the assessment of the environmental impact of MEL in the Peruvian Andes using as an example two post-mining sites in the Hualgayoc district. This evaluation includes the study of soils and native plant species in terms of their metal accumulation potential and the species involved in the process, in order to generate information on a possible use of Andean native plants for phytoremediation. The mineralogical composition of soils is dominated by illite, kaolinite, quartz, and jarosite. Soil analyses also reveals a high acidity, very low content of essential nutrients, and potentially toxic concentrations of Pb, Cd, As, Cu, Ag, and Zn out of the 34 analysed elements. Sequential fractionation soil analyses indicate that the highest content of the metals is in fractions with limitedmetal mobility. Soils are classified as extremely polluted according to several geochemical indexes, thus represent a serious risk to the local ecosystem. The main part of the project concerns native Andean flora and contributes to their inventory with the identification of 22 plants belonging to 12 family species. The metal content in plant organs is correlated with that of the soil, in order to assess the phytoremediation potential of native plant species by establishing their metal bioaccumulation and translocation capabilities. Some plants are found to be potentially suitable for phytoremediation of Cd, Cu, and Zn but none of them for Pb, As, and Ag. The speciation studies carried out by HPLC with parallel elemental (ICP) and molecular (ESI) mass spectrometricdetection allows the identification of the chemical species responsible for the translocation of Cu and Zn. Nicotianamine complexes are the major species of copper and zinc in organs of Arenaria digyna, Nicotiana thyrsiflora and Puya sp.; they are accompanied by deoxymutageneic acid complexes. In addition, a novel, never reported so far, dihydroxy-nicotianamine species was identified as the most abundant Cu and Zn ligand in Hypericum laricifolium.L'exploitation minière des métaux est l'un des piliers économiques de l'économie péruvienne. Le Pérou est le principal producteur d'or, de zinc, de plomb et d'étain d.Amérique latine et le deuxième producteur mondial de cuivre, d'argent et de zinc. Malgré son importance économique, l'exploitation minière a également laissé une pléthore de Responsabilités Environnementales Minières (REM) dont la gestion inadéquate des déchets représente un risque pour l'environnement et la santé humaine et est un déclencheur courant de problèmes sociaux. La région de Cajamarca est la deuxième région du Pérou en termes de nombre de sites REM, la majorité d'entre eux étant situés dans le district de Hualgayoc. L'objectif du projet de doctorat est l'évaluation de l'impact environnemental des REM dans les Andes péruviennes en utilisant comme exemple deux sites post-miniers dans le district de Hualgayoc. Cette évaluation comprend l'étude des sols et des espèces végétales indigènes en termes de potentiel d'accumulation des métaux et des espèces impliquées dans le processus, afin de générer des informations sur une éventuelle utilisation des plantes indigènes andines pour la phytoremédiation. La composition minéralogique des sols est dominée par l'illite, la kaolinite, le quartz et la jarosite. Les analyses de sol révèlent également une acidité élevée, une très faible teneur en nutriments essentiels et des concentrations potentiellement toxiques en Pb, Cd, As, Cu, Ag et Zn sur les 34 éléments analysés. Les analyses de sol par fractionnement séquentiel indiquent que la teneur la plus élevée en métaux se situe dans les fractions pour lesquelles la mobilité métallique est limitée. Selon plusieurs indices géochimiques, les sols sont classés comme extrêmement pollués et représentent ainsi un sérieux risque pour l'écosystème local. L'essentiel du projet concerne la flore andine indigène et contribue à leur inventaire avec l'identification de 22 plantes appartenant à 12 familles. La teneur en métaux des organes végétaux est corrélée à celle du sol, afin d'évaluer le potentiel de phytoremédiation des espèces végétales indigènes en établissant leurs capacités de bioaccumulation et de translocation des métaux. Certaines plantes se révélent être potentiellement appropriées pour la phytoremédiation du Cd, du Cu et du Zn, mais aucune d'entre elles pour le Pb, l'As et l'Ag. Les études de spéciation réalisées par HPLC avec détection par spectrométrie de masse parallèle élémentaire (ICP) et moléculaire (ESI) permettent d'identifier les espèces chimiques responsables de la translocation de Cu et Zn. Les complexes de nicotianamine sont les principales espèces de cuivre et de zinc dans les organes d'Arenaria digyna, de Nicotiana thyrsiflora et de Puya sp.; ils sont accompagnés de complexes d'acide désoxymutagénique. En outre, une nouvelle espèce de dihydroxy-nicotianamine, jamais signalée à ce jour, est identifiée comme le ligand Cu et Zn le plus abondant dans l.Hypericum laricifolium.La minería metálica es uno de los pilares económicos de la economía peruana. Perú es el principal productor de oro, zinc, plomo y estaño de América Latina y es el segundo productor mundial de cobre, plata y zinc. A pesar de su importancia económica, la minería también ha dejado una gran cantidad de Pasivos Ambientales Mineros (PAM) cuya inadecuada gestión de residuos representa un riesgo tanto para el medio ambiente como para la salud humana y es un desencadenante habitual de problemas sociales. La región de Cajamarca es la segunda del Perú en número de PAM y la mayoría de ellos se encuentran en el distrito de Hualgayoc. El objetivo del proyecto de doctorado es la evaluación del impacto ambiental de PAM en los Andes peruanos utilizando como ejemplo dos emplazamientos post-mineros en el distrito de Hualgayoc. Esta evaluación incluye el estudio de los suelos y de las especies vegetales nativas en cuanto a su potencial de acumulación de metales y las especies involucradas en el proceso, con el fin de generar información sobre un posible uso de las plantas nativas andinas para fitorremediación. La composición mineralógica de los suelos está dominada por illita, caolinita, cuarzo y jarosita. Los análisis del suelo también revelan una elevada acidez, un contenido muy bajo de nutrientes esenciales y concentraciones potencialmente tóxicas de Pb, Cd, As, Cu, Ag y Zn de entre los 34 elementos analizados. Los análisis de suelos por fraccionamiento secuencial indican que el mayor contenido de los metales se encuentra en las fracciones con movilidad limitada de los metales. Los suelos se clasifican como extremadamente contaminados según los índices geoquímicos, por lo que representan un grave riesgo para el ecosistema local. La parte principal del proyecto se refiere a la flora nativa andina y contribuye a su inventario con la identificación de 22 plantas pertenecientes a 12 especies familiares. El contenido de metales en los órganos de las plantas es correlacionado con el del suelo, con el fin de evaluar el potencial de fitorremediación de las especies de plantas nativas estableciendo su capacidad de bioacumulación y translocación de metales. Algunas plantas resultan ser potencialmente adecuadas para la fitorremediación de Cd, Cu y Zn, pero ninguna de ellas para Pb, As y Ag. Los estudios de especiación realizados por HPLC con detección elemental (ICP) y molecular (ESI) de espectrometría de masas en paralelo permiten identificar las especies químicas responsables de la translocación de Cu y Zn. Los complejos de Nicotianamina son las principales especies de cobre y zinc en órganos de Arenaria digyna, Nicotiana thyrsiflora y Puya sp.; están acompañados por complejos de ácido desoximutagénico. Además, se identifica una nueva especie de dihidroxi-nicotianamina, nunca reportada hasta ahora, como el ligando de Cu y Zn más abundante en Hypericum laricifolium