Conference Agenda

Climate change, driven by global warming and unstable weather patterns, is creating critical challenges for modern food production. One significant concern is the growing prevalence of plant pathogens in cereal crops, particularly species such as Fusarium graminearum and Fusarium culmorum. These fungi produce harmful secondary metabolites known as mycotoxins, which pose a serious threat to global food safety. Consequently, there is a growing need for analytical tools that enable rapid, sustainable, and on-site detection and monitoring of such contaminants.

This presentation introduces innovative spectroscopic technologies designed for real-time mycotoxin detection throughout the food supply chain. A portable IR-ATR device has been developed for quick, on-site screening at critical control points, such as farms, transport stages, and storage facilities. In parallel, a high-precision laser-based analyzer system offers confirmatory analysis at goods reception points and within laboratory settings. The effectiveness and reliability of these systems for detecting mycotoxins will be demonstrated, highlighting their value in food safety monitoring. Furthermore, the presentation explores the potential to extend these technologies to pesticide detection, offering a promising avenue for comprehensive quality assurance in the agri-food sector.

Acknowledgment: This work was supported by the EU Horizon 2020 project PHOTONFOOD [#101016444] which is part of the PHOTONICS PUBLIC PRIVATE PARTNERSHIP and Financial support programmes for female researchers, Office for Gender Equality, Ulm University.

Analytical spectroscopy plays a leading role in the characterization of nanomaterials. An exhaustive (nano)materials characterization and the appropriate choice of methodologies for nano-toxicological risk assessment promise nowadays a reliable and accurate data output to guarantee their safe application in real-life products. In this communication, analytical spectroscopy was used to guide and support the production of human-safe polymer composites modified with copper particles, for food packaging applications.

Reducing agrifood waste has become an important goal, considering that up to 50% of total production is lost due to contamination by harmful microorganisms. In this context, controlling the interface between food products and the external environment can be a powerful tool to prevent waste. The aim of this study was to produce a bio-based and biodegradable food packaging material loaded with copper particles, which act as an antimicrobial reservoir.

A green one-pot approach was used to synthesize copper particles using poly(N-vinylpyrrolidone) (PVP) as a capping agent (Cu@PVP), preventing aggregation through steric hindrance and eliminating the need for an inert atmosphere [1]. The influence of PVP and reductant concentrations, as well as reaction time, on the oxidation state of copper, kinetics, and particle size was investigated by varying each of these parameters individually [2]. Optimal conditions were identified to obtain an average particle diameter above 200 nm, while minimizing reagent and time consumption, to prevent nano-cytotoxicity effects. After a purification step, the Cu@PVP particles were suspended in ethanol and embedded in a chitosan (CS) polymeric matrix.

Composite films were obtained by solvent casting [3]. The polymer solution concentration was adjusted to maintain good rheological properties even in the presence of inorganic particles. Torsional rheology and water uptake measurements were performed to assess the mechanical behavior of the self-standing films obtained after solvent evaporation. The antimicrobial capabilities were demonstrated by ionic Cu²⁺ release kinetics, and in vitro by growth inhibition of three different model fungi responsible for agrifood spoilage.

A thoughtful spectroscopic characterization was performed on Cu@PVP particles and composite films, by UV-Vis, Fourier transform infrared (FT-IR) and X-ray photoelectron (XPS) spectroscopies. Both films and particles have been also characterized morphologically by transmission (TEM), atomic force (AFM), and scanning electron (SEM) microscopies.

This innovative material could be used for the production of biodegradable bags and envelopes destined to the storage of fruits and vegetables, extending the shelf-life of these horticultural products.

References:

[1] M.C. Sportelli et al., Chem. Eur. J., 2023, 29, e202203510. DOI: 10.1002/chem.202203510.

[2] D. d’Agostino et al., Food Chem., 2025, 464, 141823. DOI: 10.1016/j.foodchem.2024.141823.

[3] E. Kukushkina et al., IJMS, 2022, 23, 15818. DOI: 10.3390/ijms232415818.

Arsenic speciation is essential in environmental and toxicological studies due to the distinct toxicity and bioavailability of its chemical forms. High-performance liquid chromatography coupled with inductively coupled plasma mass spectrometry (HPLC-ICP-MS) is a widely accepted technique for this purpose, offering high sensitivity and selectivity. However, its analytical performance is critically dependent on both the chromatographic separation conditions and the efficiency of the sample introduction system, which influences analyte transport, signal stability, and matrix effects.

In this work, an HPLC-ICP-MS method was developed and optimized through the integration of two advanced strategies: the use of the high-temperature Torch Integrated Sample Introduction System (hTISIS) as sample introduction system, and the Single Injection Calibration Approach (SICA). The hTISIS operated at the optimized temperature of 150 °C and ultra-low liquid flow rates (45 µL min⁻¹), achieving nearly complete solvent evaporation in the chamber, reduced memory effects, and enhanced analyte transport efficiency. Compared to a conventional double-pass spray chamber, hTISIS improved sensitivity by an order of magnitude, achieving limits of detection as low as 0.09 µg kg⁻¹ versus 0.47 µg kg⁻¹ with the conventional one. Its compatibility with microflow conditions supports more sustainable and cost-effective analytical workflows.

Quantification was carried out using SICA which generated the calibration using a single standard injection. This approach shortened calibration time and reagent consumption by up to 75% compared to conventional multi-point calibration, while maintaining excellent linearity (R² > 0.999) and precision (RSD < 10%). The method was validated using two certified reference materials (Frozen Human Urine SRM 2669 with two different concentration levels and Apple Juice SRM 3035), achieving excellent accuracy, and providing recoveries ranging from 92 to 110%. Chromatographic separation was performed on a PRP-X100 anion-exchange column (5 µm, 150 × 2.1 mm) under gradient elution with 60 mmol L⁻¹ ammonium bicarbonate (pH 8.7) and 5% methanol, allowing baseline resolution of arsenite (As³⁺), arsenate (As⁺⁵), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), and arsenobetaine (AsB) within 12 minutes.

The method was successfully applied to the analysis of commercial fruit juice samples, where trace levels of arsenic species were detected, with As⁵⁺ being the predominant species. These results were consistent with previously reported data, being inorganic arsenic concentrations in juices ranging from 10 to 80 µg kg⁻¹, and confirmed the method applicability for routine food safety monitoring.

The rise of biodegradable polymers as sustainable alternatives to conventional plastics is currently posing significant challenges, particularly regarding the waste management of bioplastic products and assessing the actual environmental benefits of this progressive substitution. It is well established that bioplastics degrade poorly under anaerobic conditions, often resulting in the persistence of unwanted residues in the digestate, which may subsequently lead to their release into the environment. In this work, hyperspectral imaging (HSI) in the short-wave infrared range (SWIR: 1000–2500 nm) was explored as a fast and non-destructive technique for the monitoring of micro-bioplastics (MBPs) presence in digestate. For this purpose, four different commercial bioplastic products, a cup, plate, coffee capsule and shopper, were analysed by HSI before and after 14 and 30 days of thermophilic anaerobic digestion to evaluate the possibility of their identification in digestate at different stages of degradation. The analyses were carried out at the RawMaLab (Raw Materials Laboratory) at Sapienza University of Rome (Rome, Italy) using the SisuCHEMA XL^TM chemical imaging workstation (Specim, Spectral Imaging Ltd, Finland). Hyperspectral images were acquired using two different spatial resolutions (150 µm/pixel and 30 µm/pixel). The investigated samples were subdivided into a calibration and a validation dataset. The calibration dataset consisted of MBPs obtained by mechanically powdering the four different bioplastic products, which were further divided into two different size fractions (1 – 0.5 mm and < 0.5 mm), therefore obtaining 8 different samples (one for each bioplastic type and size fraction). The samples were manually placed onto individual cellulose filters, previously covered with a thin layer of digestate and dried at room temperature, to simulate the combination between the two materials (bioplastics and digestate). The dataset was acquired using the two spatial resolutions obtaining in total sixteen hypercubes. The validation dataset consisted of the final digestates coming from the anaerobic biodegradation of the four products after 14 and 30 days, that were sieved at 0.84 mm to remove larger undegraded bioplastic particles, then sampled and spread on cellulose filters and dried at room temperature. The resulting eight filters (one for each bioplastic type and biodegradation stage) were examined for the presence of MBPs which could not be separated mechanically. The filters were acquired using the two spatial resolutions, obtaining also for this dataset a total of sixteen hypercubes. Chemometric techniques were applied on the acquired hypercubes for data processing using the MATLAB^® environment (R2024a, The Mathworks, Inc., USA). On calibration dataset exploratory data analysis was performed using Principal Component Analysis (PCA) to evaluate spectral variability and to identify the best preprocessing algorithms. The PCA results revealed differences in the average reflectance spectra between MBPs and the digestate matrix. Following this exploratory analysis, a 5-classes (four different MBPs classes and one digestate matrix) Hierarchical Partial Least Squares-Discriminant Analysis (Hi-PLS-DA) model was developed for automatic classification purposes. The classification model was applied to the validation dataset demonstrating a robust discrimination between the four different MBP types and the digestate matrix. This approach provides a promising strategy for the real-time identification and quantification of MBP particles in complex environments. The research demonstrates the potential of HSI, combined with advanced chemometric data analysis, as an effective tool for fast, non-invasive identification and classification of different bioplastics. The ability to detect and classify MBPs in digestate offers valuable insights into the monitoring of the anaerobic digestion process and the quality of the final products, which can serve as a first step for assessing potential contamination and associated toxicity effects.

In recent years, insects have garnered significant attention as a more sustainable protein source, offering advantages over traditional animal-based proteins. In addition to being protein-rich, insects provide good nutritional value, including bioactive compounds such as vitamins, minerals, and long-chain polyunsaturated fatty acids. However, they can also bioaccumulate toxic elements from the environment. Since the consumption of insects constitutes an interesting sustainable source of essential elements to the diet, but also a source of toxic elements, it is important from a food quality perspective, to evaluate the bioaccessible fraction for each relevant element, defined as the fraction that is released from the food matrix into the gastrointestinal tract and has the potential to be absorbed and transformed into bioactive species. In this regard, in vitro approaches are good alternatives to imitate what naturally occurs during the human digestive process. In this study, aluminium, copper, iron, lead, manganese, and zinc were evaluated. Wild insect samples were collected in January 2024 and characterized by an entomologist as Chromacris speciosa, Diloboderus abderus, and Gryllus assimilis. Afterwards, samples were lyophilized and then triturated and homogenized by means of a ball mill. The gastric solution consisted of 3 g L^-1 pepsin in 12 mol L^-1 HCl, pH 1.3, while the intestinal solution was 2 g L^-1 bile salts and 5 g L^-1 pancreatin in 0.2 mol L^-1 NaOH, pH 6.8. A portion of 0.5 g of dried sample was placed into a 25 mL flask with 5.0 mL of gastric solution and shaken in vortex for 2 min. The mixture was then kept in a water bath with orbital shaking at 37 °C for 2 h. Prior to intestinal digestion, the pH of the previously obtained solution was adjusted to 6.8. Then, 5.0 mL of intestinal solution were added, the mixture was shaken in vortex for 2 min and incubated again at 37 °C for 2 h. Finally, the mixture was centrifuged at 28,000 g for 30 min and the supernatant separated from the residue and used for bioaccessible fraction determination. The bioaccessible fraction (BF) was calculated as: BF (%) = (RF/TC) × 100, where RF was the released fraction of the element and TC was the total concentration of the element. To evaluate the accuracy of the assay, the corresponding mass balance was performed. For the determination of total concentrations in samples and residues a microwave-assisted acid digestion was carried out. Briefly, 0.5 g of sample was accurately weighted into each reaction vessel and 10.0 mL of 4.5 mol L^-1 HNO₃ was added. The program consisted of a 15 min ramp time until 200 °C, holding for 15 min, and then cooling to room temperature. After mineralization samples were filled up to 10.0 mL with ultrapure water. Analytical determinations were performed by microwave induced plasma optical emission spectrometry (MIP OES) using an Agilent 4210 spectrometer with an inert One Neb nebulizer with a double-pass glass cyclonic spray chamber system and a standard torch. The spectrometer used an online nitrogen generator. Operational conditions such as pump speed, nitrogen flow, and viewing position were thoroughly optimized for each element. The plasma gas flow was fixed at 20 L min^-1 and the auxiliary gas flow at 1.5 L min^-1. The following operational settings were applied: uptake time of 70 s, plasma stabilization time with sample aspiration of 15 s, read time of 3 s (in triplicate), wash time of 20 s, wavelengths 396.152 nm (Al)/ 324.754 nm (Cu)/ 371.993 nm (Fe)/ 403.076 nm (Mn)/ 405.781 nm (Pb)/ 213.857 nm (Zn). Automatic background correction was used. The obtained bioaccessible fractions agreed with previous results reported by our research group in similar European species. MIP OES turned out to be a very efficient and green alternative for the sequential evaluation of essential elements for bioaccessibility assays, used for the first time for this purpose here in this work, to increase the knowledge about the nutritional potential of these sustainable food sources.

Nutrient-solubilizing microorganisms have been increasingly investigated for the development of bio-based agricultural inputs due to their production of metabolites such as organic acids, which are known to solubilize phosphate rock. Citric, oxalic, and malic acids are examples of organic acids produced by microorganisms that play a critical role in nutrient dissolution. In this context, this biotechnological strategy can be explored as an alternative method to solubilize analytes during the sample preparation step for elemental determination by plasma-based techniques. In this study, we evaluated the performance of organic acids (citric, oxalic, and malic) produced by Aspergillus niger under solid-state fermentation in sugarcane bagasse, aiming to solubilize nutrients and contaminants elements from various sample types during sample preparation for elemental determination by inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP OES). The fermentation and acid extraction conditions were based on the methodology described by Klaic et al. (2020)¹, which optimized the production of organic acids by Aspergillus niger (strain 763). Certified reference material of tomato leaves (SRM 1573a, NIST, USA) and a reference material of mineral supplement (RM-Agro E2001a, Embrapa Pecuária Sudeste, Brazil), were submitted to sample preparation using the organic acid medium diluted with deionized water. The extractions were performed using three approaches: extraction block (120 min at 90 °C), ultrasound-assisted extraction (60 min at 50 °C), and microwave-assisted extraction (up to 120 °C). Recoveries for tomato leaves ranged from 82–86% for K, 69–81% for Mg, 62–72% for Mn, 89–102% for Na, and 50–60% for P (determined by ICP-OES). For the mineral supplement, recoveries ranged from 96–97% for As and 79–80% for Cd (determined by ICP-MS). According to the t-test, no statistically significant difference was observed between the concentrations obtained using the digestion block and ultrasound-assisted extraction methods. Additional studies are underway to evaluate other matrices, acid concentrations, and extraction temperatures. The results indicate that the organic acid medium produced by microorganisms shows strong potential for solubilizing nutrient and contaminant elements. This approach is compatible with plasma-based analytical techniques and represents a promising and sustainable alternative for sample preparation.