By Jörn Migge, head of product & market management, Mettler-Toledo Product Inspection
The integrity of dairy products, especially those packaged in plastic cups such as yoghurt, cream cheese and ice cream, relies heavily on precise and hygienic weighing processes. Facilitating accurate weights while maintaining stringent hygiene standards presents unique challenges for manufacturers. Understanding these and other challenges, and the innovative checkweighing solutions to tackle them head-on, can help make a great dairy production line as we explore in this article.
Challenges of weighing plastic cups in the dairy industry
Weighing plastic cups filled with dairy products presents unique challenges, primarily due to the diverse filling processes employed. There are two main types of filling processes: linear fillers and rotary fillers. Linear fillers process cups in groups, often in multi-lane applications, where cups exit the system in groups of four or six.
To minimise packaging waste, some manufacturers use checkweighers before sealing the cups and then again afterward to comply with pre-packaged goods legislation, which mandates strict adherence to weight and labelling standards.
Proper sealing is critical to prevent contamination, as improperly sealed cups or those that break during production and transportation can compromise product safety and quality. If cups break, they can create a mess that contaminates other products on the line, necessitating frequent pauses in production to clean and maintain a sterile environment.
Additionally, the fragile nature of plastic necessitates regular cleaning to prevent contamination both inside and outside the product. Balancing the need to reduce packaging waste while adhering to product safety and compliance with regulations remains a critical challenge in the dairy industry.
How smart design plays an important part in the process
Smart design is crucial to facing these challenges head-on, and to the efficiency and hygiene of the checkweighing process. A key aspect for any dairy manufacturing line is the washdown design of a checkweighing system. Manufacturers should look for solutions that offer temperature-resistant load cells, which allow for quick re-zeroing after cleaning, significantly reducing downtime. Easy-to-remove belts can also help to facilitate fast cleaning, meaning that equipment can be swiftly sanitised to prevent biological contamination.
Another key element of any good checkweighing solution is its ‘Poka Yoke’ design – dairy manufacturers should look for one that offers foolproof reassembly, making it easy for even less experienced personnel to reassemble the equipment correctly. Advanced load cell technology, such as the FlashCell Electro-Magnetic Force Restoration (EMFR) load cell, can offer high accuracy and can handle throughputs of up to 250 packs per minute. This is essential for maintaining product integrity and compliance, as well as maximizing production throughput.
The placement of the checkweigher on the production line is also a critical design consideration. Early detection of weight deviations allows for immediate feedback to the filling machines, meaning that any errors are quickly corrected. This feedback mechanism is vital in high-speed production environments, where maintaining consistency and quality across large batches is challenging.
The C33 PlusLine and PlusLine WD checkweighers from Mettler-Toledo, for instance, are designed to support challenging weighing applications in environments prone to product spillage, such as those involving dairy products. These systems offer features that cater specifically to the needs of the dairy industry, including resistance to frequent wet cleaning routines and quick re-start capabilities after cleaning.
Benefits of smartly designed washdown solutions
Washdown solutions offer several benefits that are particularly important for dairy manufacturers that use plastic cup packaging formats. These solutions provide easier and more effective cleaning processes, reducing the risk of biological contamination. The durability of washdown designs under harsh cleaning conditions, such as those involving butter or ice cream, means that the equipment can withstand rigorous cleaning routines. This design also minimises product waste by facilitating the quick removal and washing of conveyor belts, allowing for fast reassembly and reducing downtime.
The ability to quickly re-zero temperature-resistant load cells after cleaning allows manufacturers to restart production almost immediately, maintaining high productivity while adhering to strict hygiene standards. This efficient design also helps in complying with regulatory requirements, meaning that products meet all necessary health and safety standards. Monitoring and feedback capabilities also supports real-time adjustments to filling heads, efficiently correcting any filling errors and minimising product giveaway.
By using checkweighers with at least IP65 ingress protection, manufacturers can enhance operational efficiency, reduce contamination risks and garner consistent product quality.
Compliance and quality control
Compliance with pre-packaged goods regulations is another critical concern for dairy manufacturers. Weighing closed cups accurately is essential for maintaining product weight accuracy and meeting these regulatory requirements. The E-mark, which can only be applied if the package has been weighed after sealing, is a part of these regulations, making sure that products are weighed and sealed correctly before they are marked. This process verifies the product weight and, if all parameters are met, the products receive the E-mark, indicating compliance with pre-packaged goods legislation.
The role of additional systems, such as x-ray inspection and metal detection solutions, in quality control is also significant. These systems identify contaminants that might otherwise go unnoticed, providing an additional layer of safety and quality assurance. Integrating these systems with washdown checkweighers offers a comprehensive approach to contamination detection and weight verification. This integration helps to see that products leaving the production line meet the highest standards of safety and quality, thereby enhancing consumer trust and maintaining regulatory compliance.
Conclusion
Smart design, particularly in washdown checkweighers, plays a crucial role in overcoming the challenges associated with weighing plastic cups in the dairy industry. By facilitating easier cleaning, reducing contamination risks and improving compliance with regulations, advanced checkweighing systems can help to enhance overall operational efficiency and product quality, ultimately helping to achieve peace of mind and robust performance in even the most demanding production environments.
