Food processing plants can be a source of microbiological and physical contamination of food that can have implications for worker health and safety.
Their cleaning and maintenance are an important aspect of the safety of each activity, to avoid possible phenomena of both physical and microbiological contamination of food that is processed. Moreover, cleaning activities have economic and environmental implications related to the necessary downtime of the machines and the use of solvents.
The industrial plants of the Food and Packaging sector are always performing in terms of production capacity, however, this implies the adaptation of safety standards today made possible by the use of innovative materials and technologies.
Italy is the world leader in the Agrifood sector, but also in the production of automatic machines for processing, and packaging and technological innovation is essential to maintain this position.
Demetra stands for DEvelopment of MatErial and TRAcking technologies for the safety of food: the objective of the project is not only aimed at the identification of advanced technical/scientific solutions, transversal to the production and packaging sectors, through the study of innovative materials and Surface Engineering; one part of the project concerns cybersecurity and aims to develop an integrated system of technologies for the increase of safety, food quality and eco-compatibility in the food industry, through the marking and tracking of Agrifood products.
The project to preserve food safety
The Demetra project is divided into three macro-lines characterized by a high degree of innovation independent of each other, but whose combination would amplify their potential.
1) Advanced material technologies (nickel-free steels) and surface treatments (laser textured) for food-contact parts in processing and packaging plants in order to:
- to facilitate the removal of possible organic residues from food products and prevent the release of potentially harmful elements;
- to ensure increased food safety and plant productivity;
- to decrease environmental impact by reducing the use of solvents/sanitizers and water consumption.
The goal is to improve the cleanability of facilities and reduce the risk of the release of potentially harmful elements into food.
2) Information systems based on blockchain architecture and advanced cryptographic solutions to track all salient events related to the entire chain of production, processing, transportation and sale of products, contributing to the safety of the food chain
3) Highly innovative marking system based on objects that, due to their architecture, are inherently non-reproducible and through the application on the packaging will uniquely associate a specific product with the information contained in the tracking system operating, also, in synergy with existing anti-counterfeiting policies.
Finally, the Demetra project aims to integrate the three technologies described above into a marking and tracing system that could form the basis for the eventual establishment of a quality mark for foods produced and packaged with nickel-free equipment.
Participating parties and funding
The company CSM Rina Consulting – Centro Sviluppo Materiali S.p.A. is the lead partner in the Demetra project.
Ecor International participates with Net Service, University of Calabria and Poste Italiane.
The resources required for the Project’s interventions are funded by the Ministry of University and Research (MUR), in the form of a contribution in expenditure, from the availability of PON “Research and Innovation” 2014-2020 and FSC Funds.
Ecor International’s role in food safety
The Food industry is Ecor International’s historical business area, within which it carries out prototyping, validation, and production of critical mechanical components in stainless steel and special alloys and assembly of electromechanical systems and subsystems for automatic processing and packaging machines, operating as a strategic and integrated supplier of important players in the sector.
Its main skills also cover physical (Test Rig) and numerical simulation inherent in accelerated life cycle testing, subsystem analysis, system robustness enhancement, and new technologies/materials for the food industry, advanced mechanics, and aerospace.
Ecor International is taking part in the Demetra project with the aim of developing an integrated system of technologies for increasing food safety and quality and environmental friendliness in the food industry.
Specifically, it defines the specifications and acceptance criteria that steels will have to meet, in terms of food compatibility and resistance to cleaning cycles.
Two approaches have been identified to achieve the goal:
- To reduce the presence of elements whose toxicological effects have been established, specifically nickel, by replacing austenitic steels characterized by a presence of Nickel higher than 8%, with ferritic ones, which do not contain it.
- To reduce bacterial growth on the parts most exposed to the phenomenon and to improve surface cleanability, which are widespread problems in the food packaging sector, given the considerable exposure to the risk of food contamination.
The results Ecor International aims to achieve concern:
- compatibility data, qualifications, and parameters for innovative surface treatments on nickel-free steels.
- Optimized parameters for laser texturing and PVD technology coatings to improve cleanability and sanitization, with characterization data, particularly food compatibility, for their certification in the area of interest.
Food safety: which weld and which material to use?
To make food plants safer and, consequently, minimize the presence of elements with known toxicological effects, such as nickel, Ecor International uses its technological expertise in the study of surfaces and materials, testing the response of different steels, ferritic and austenitic, to different types of welding. Indeed, welding can affect the mechanical and chemical properties of materials, particularly those related to corrosion, and geometric distortions can occur with potential stagnation of food liquids that promote bacterial growth and proliferation.
Based on the identified specifications, commercial nickel-free steels potentially suitable for food contact applications were identified; for corrosion resistance reasons, research focused on ferritic stainless steels.
During this period, different types of samples representative of industrial machine components were selected, in the form, for example, of plate, tube, or welded joint, making specimens in AISI 304L and/or 316L for comparative tests between TIG and laser welding.
Welded joints are homogeneous when made between 470Li specimens and heterogeneous when made between 304L and 470Li.
In some specimens made by pairing austenitic and ferritic steels with TIG welding, the formation of Widmanstätten ferrite was verified.
The choice of process engineering, therefore, fell on laser welding, which is specific for smaller welds and able to work without losing precision and quality of the result, thanks to its lower heat input that avoids alterations in the characteristics of metals, both ferritic and austenitic ones.
Food safety through surface treatments
Food safety is also achieved by reducing any risk of bacterial contamination/growth and/or other pathogens (such as, for example, fungi) on some sensitive parts of the plant. This situation occurs predominantly where stagnation of organic liquids or parts of food may lead to local bacterial growth, in the event of contamination, resulting in compromised food.
A situation, however, that can be avoided or reduced by special surface treatments and by realizing superhydrophobic coatings, using laser technology, to superficially ablate steel to create hierarchical structures on a micro-metric and sub-micrometric scale, which give superhydrophobic characteristics by reducing bacterial adhesion and proliferation.
The focus is on the development and laboratory-level verification of surface treatments aimed at increasing the cleanability of component surfaces of equipment for the processing and the packaging of food.
Ecor International engineers are working to identify solutions using austenitic (304L and 316L) and ferritic (470Li) stainless steels under various surface conditions to test their effect on coating adhesion.
The phase began with the identification of the specifications and acceptance criteria that the coatings must meet, in terms of food compatibility and resistance to cleaning cycles.
Following an analysis of the critical parts in the plants, various types of samples were prepared: flat plate, tube, welded joint to recreate real conditions, on specially made test benches, selecting some aggressive food products (e.g., milk and tomato sauce).
The surfaces were treated by laser texturing technology through pulsed-beam laser scanning.
Depending on the laser parameters (type, frequency, intrinsic and extrinsic elements), different types of microstructures were obtained, with a greater bias toward bumps, which demonstrated markedly superhydrophobic properties.
Tests showed that the laser textured surfaces demonstrated reduced bacterial growth compared to the as-is ones, demonstrating the effectiveness of the laser treatment.
In addition to the laser treatment, the food-contact surfaces were coated with PVD (Physical Vapor Deposition) technology.
Tests conducted on laser textured specimens coated through PVD technology demonstrated improved hydrophilicity and, consequently, improved cleanability when using water-based solutions.
A result that can be read under different keys because, in addition to allowing better cleanability of the machine, it has other advantages related to cyclic washing, such as:
- to reduce the dangers of corrosion (due both to the presence of food and from the use of aggressive detergents);
- to reduce plant downtime required for cleaning;
- to increase production efficiency (increasing output and reducing costs);
- to reduce the use of detergents.
There are not only positive aspects from an economic and management point of view, but there are also environmental ones.
As reported by Ivan Moretti, Research&Innovation Manager of the project, “The results of the analysis performed on the welds showed better performance in the laser welding process compared to TIG welding with particular reference in welds between austenitic and ferritic steel. The elements that most favour the laser welding technology are the lower deformations related to the reduced heat input and a better microstructure with no formation of unwanted phases.”
Regarding the laser welding between two pieces of 470Li and 304L steel, Moretti explains that “the main difficulties of the operations were represented by the optimization of the welding process and the realization of superhydrophobic surfaces, through laser technology, which favour sanitization and cleanability. These surfaces were realized through bumps microstructures on flat and cylindrical substrates of AISI 316L steel that allowed to provide markedly superhydrophobic properties.” continues Moretti.
“Currently, we are in the testing phase to verify the integrability of the systems between material and process developed on the components of industrial machines for Food Packaging by simulating the washing cycles to which they are subjected”.
Food safety through marking and traceability
Another part of the DEMETRA project is the cutting-edge Agrifood product marking system, based on objects that are inherently non-reproducible (non-cloneable) due to their nano/microstructure.
The purpose of this phase is to uniquely associate a specific product with the information contained in the tracking system, thus also returning a powerful anti-counterfeiting tool: in fact, each label acts as the fingerprint of the product and is readable at different security levels:
- Overt for the end consumer.
- Semi-Overt for the distribution chain.
- Covert for litigation with legal value.
To maximally protect both the production and the distribution of food, the other partners are identifying innovative solutions to protect information security in the logistics and supply chain of agri-food products. Specifically:
The development and definition of information systems based on Blockchain architecture and advanced cryptographic solutions to track all salient events related to the entire chain of production, processing, transportation, and sale of products.
The development of an online sales platform for agribusiness supply chain products fully integrated into the Blockchain-based framework, capable of improving sales opportunities for target products, ensuring the security of payment transactions, and promoting tracked logistics services for retail and large-scale retail customers.
The identification of innovative methodologies for determining, monitoring and mitigating cyber risk, protecting the entire planned infrastructure.