By Miriam Krechlok, segment marketing manager, Mettler-Toledo
Ready meals today offer more than just convenience. From dehydrated noodles to sauced pasta dishes and frozen lasagne, they have become a sophisticated product category. Each type of ready meal, whether dry, wet, chilled or frozen, poses unique challenges regarding quality and safety throughout the production process. Manufacturers must adapt their inspection protocols to suit these varying production methods while meeting regulatory compliance and consumer satisfaction.
In this article, we will explore product inspection solutions tailored for different ready meal categories, addressing the Critical Control Points (CCPs) in the production of dry, wet and frozen applications, as well as those areas on production lines that are not typically considered CCPs. By being confident that ready meals are free from contaminants, properly labelled and consistently portioned, manufacturers can uphold the highest standards of food safety and quality while optimising their production processes.
The importance of inspection technologies
Inspection technologies, such as metal detection, x-ray inspection, vision inspection and checkweighing and are crucial for maintaining the integrity and safety of ready meals. They help detect physical contaminants, achieve proper labelling and confirm consistent portion sizes, ultimately supporting manufacturers in meeting consumer expectations and regulatory requirements.
Challenges in dry ready meal production
Dry ready meals, such as instant noodles, dehydrated soups and rice mixes, present specific challenges in ensuring safety and quality throughout their production process. One of the primary issues is the generation of dust and fine particles during production. These particles can obscure contaminants, making detection difficult as they interfere with inspection systems. Advanced contaminant detection technologies can overcome this as explained later in this article.
Importance of hygiene and ingredient distribution
Once the ingredients are fried and dried, maintaining hygiene becomes critical, and confirming packaging integrity is essential to prevent moisture from compromising product freshness. Additionally, achieving even distribution of ingredients, such as flavouring in a rice mix, is vital for consistent product quality. Each stage of dry ready meals production, from ingredient mixing to final packaging, requires vigilant quality control to help uphold safety and uniformity.
Example in action: instant noodles
Take the production of instant noodles as an example. This popular meal involves several key steps, each presenting its own inspection challenges:
- Raw material inspection: The process begins with inspecting incoming raw materials, such as flour and oil. Advanced metal detection systems are employed early in the process to screen these ingredients for ferrous and non-ferrous metals and stainless steel, capturing contaminants before they can enter the production line. The product format will dictate the type of metal detector used – for bulk powders and granules a gravity fall system is ideal; a pipeline system can be used for liquids or pastes, packaged raw materials can be inspected using a conveyorised system.
- Mitigating explosion risk: Inspection of dusty, powdered products such as flour carries a potential explosion risk. If using a metal detection system at this stage, it is important to select one with a suitable design that complies with explosion prevention regulations such as ATEX/IECeX. There are selected gravity fall metal detection systems specifically designed for these types of applications at this point in the process.
- Dough creation and product effect: During the dough creation stage, maintaining the purity of the dough is crucial. However, manufacturers face a phenomenon known as the product effect, where the metal detector’s magnetic field is disrupted not only by metallic contaminants but also by the product itself, particularly if it contains high moisture or salt content. In noodle dough, significant moisture can cause the water to conduct electricity, creating a magnetic response similar to that of a metal contaminant, leading to false positives that reject uncontaminated products.
- Advanced detection technology: To combat product effect, advanced metal detection technologies, such as Multi-Simultaneous Frequency systems, are employed. These systems use multiple detection frequencies simultaneously, allowing the equipment to distinguish between the product and actual contaminants. By analysing the product at two or more frequencies, the system can effectively filter out interference caused by moisture or other conductive elements, significantly reducing false rejects. This enhances accuracy and helps manufacturers avoid unnecessary waste, maintaining higher efficiency throughout the production line.
Maintaining cleanliness and safety
As noodles progress through various production stages, including sheeting, cutting, steaming and drying, the accumulation of dust particles from flour and other ingredients complicates contamination detection and poses cleanliness issues. Metal fragments from cutting blades can also be an ongoing challenge. To address these issues, regular equipment cleaning between production cycles is crucial for maintaining product safety and preventing cross-contamination. It is important to consider system design and ease of cleaning when investing in a new product inspection system.
Addressing frying and drying risks
The frying and drying stages introduce additional contamination risks from oil and fine particles. Oil can trap contaminants or coat foreign objects, complicating detection. Fine particles can obscure contaminants, particularly in dusty environments, making some inspection processes, for example x-ray, even more challenging. To address these risks, metal detection systems are employed post-frying to identify any remaining foreign bodies. Checkweighers are also utilised to confirm that portion sizes remain consistent, further supporting product quality and reducing waste.
Packaging and final inspection
During the packaging stage, x-ray technology is crucial for scanning for contaminants such as glass or plastic that may have entered the process. Agglomerates can also pose a challenge, especially in dried products where flavouring or seasoning can clump together. Advanced x-ray technology is required to differentiate between harmless clumps of ingredients and actual contaminants, while also verifying product and packaging integrity. This technology helps facilitate correct product placement in ready meal compartments and monitors consistent fill levels. Checkweighing can also be used to confirm each noodle pack contains the noodles and the additional flavour sachet by weight, meaning greater consistency in the end product.
Wet ready meals: tackling contamination and packaging integrity
Wet ready meals, including soups, stews, sauced pasta dishes and curries, also present unique challenges due to their higher liquid content and dense ingredients. These meals are often highly processed, which increases the risk of contamination. Additionally, fresh and frozen varieties face distinct challenges: fresh meals have shorter shelf lives and greater contamination risks, while frozen meals can suffer from freezer burn and thawing issues.
Example in action: soup production
In the production of soups, the process begins with inspecting raw ingredients such as vegetables, meats and grains. Since soups are considered a pumped food, they contain chunks of other foods that cannot be sieved out, making effective detection critical. Metal detection and x-ray systems are employed to screen for foreign bodies in these ingredients before they are mixed and processed. Once the mixture is pre-cooked, further inspection is required to detect any contaminants introduced during cooking or mixing.
Filling process and packaging integrity
During the filling stage, where the soup is placed into containers such as tins or pouches, advanced inspection technologies like x-ray systems come into play. These systems are highly effective at detecting contaminants through complex packaging materials, even in ridged or opaque packaging like cans, where dense liquids can obscure contaminants. X-ray technology can identify foreign bodies that may otherwise go unnoticed, helping to maintain product integrity in challenging conditions.
Weight control systems are also critical during the filling process, as they verify that each container has the correct quantity of soup, stew or sauce. Any imbalance in portions could lead to inconsistent product quality and non-compliance with weights and measures legislation, making checkweighers essential.
The integrity of packaging is particularly important for wet products, as any leakage can lead to spoilage or bacterial growth. X-ray systems help identify weak spots in the packaging that could result in leaks.
Handling and transport challenges
Handling and transporting containers, especially ridged metal cans, introduce additional hurdles. X-ray technology can manage these difficulties by inspecting cans from multiple angles to spot contaminants, even with complex packaging designs. For glass jars, special care is necessary to prevent breakages and subsequent contamination during the production process.
Chilled and frozen ready meals: inspection in low temperatures
Chilled and frozen ready meals, including pizzas, lasagnes, takeaway salads and microwaveable dinners, present unique inspection challenges. For instance, frozen pizzas require careful inspection at every stage, from dough preparation to assembly, freezing and packaging.
Continuous monitoring for safety
Metal detection and x-ray systems are employed to inspect raw ingredients like cheese and sauce for contaminants. These technologies are critical throughout the assembly line, maintaining product safety without slowing down production. As frozen products progress through the production line, inspections must be quick to prevent thawing, which can compromise both product quality and safety. High-speed metal detection and x-ray systems inspect for foreign bodies while maintaining production speeds and productivity.
Robust packaging solutions
Packaging frozen ready meals necessitates robust materials that can withstand freezing temperatures. X-ray systems check for physical contaminants even after sealing, while vision inspection systems monitor packaging integrity, identifying any leaks or damage in trays, cartons and pouches. This guarantees that packaging remains durable throughout freezing, storage, and transportation, ultimately preserving the quality of the products within.
Reducing waste and boosting productivity
Sustainability is a growing concern in the ready meal industry, with manufacturers focusing on reducing waste through early detection of contaminants in production. Early detection not only prevents waste but also boosts productivity by minimising rework and downtime.
Advanced inspection technologies assist manufacturers in combating rising costs by streamlining production and making sure that products meet both regulatory standards and consumer expectations. Integrated data management systems like ProdX from Mettler-Toledo provide real-time insights, helping manufacturers optimise their production processes, improve efficiency and ultimately lower operational costs.
Regulatory compliance and industry standards
As the demand for ready meals continues to grow, manufacturers must confirm that their products not only meet consumer expectations but also comply with stringent food safety regulations, such as the EU’s General Food Law (EC 178/2002), which holds producers responsible for the safety of their food at every stage of production, or the US Food Safety Modernisation Act (FSMA), which focuses on preventing contamination by requiring proactive safety measures.
Future trends in ready meal inspection
Demand for ever evolving inspection technologies is at an all-time high. Enhanced detection sensitivity is enabling the identification of smaller contaminants, while the integration of artificial intelligence (AI) and machine learning is improving accuracy and reducing human error.
Real-time data analysis is becoming more prevalent, allowing manufacturers to address issues immediately. Integrated inspection systems, combining multiple methods, are simplifying quality control and boosting efficiency across production lines.
By leveraging cutting-edge product inspection technologies and data management solutions, manufacturers can maintain the highest standards of safety and quality while adhering to critical regulations.
Conclusion
The landscape of ready meals is changing, and manufacturers are tasked with the challenge of meeting heightened consumer expectations for safety and quality. Through advanced inspection technologies and robust data management systems, they can rise to this challenge, boosting productivity, combating rising costs and supporting sustainability efforts by reducing waste in the process.
