Food safety considerations for robot system

Hygienic design of robotic automation solution helps food companies to eliminate the risk of microbial contamination. In a four-part series of articles, we zoom in on the best hygienic practices to design robotic automation solutions. In this second part we address the risk and hazard analysis process as first step to take when you consider to introduce a robot in contact with food.  

Within the framework of the project ColRobFood, we were interested in the challenges faced by Flemish companies in integrating robots in food production with the hygiene constraints in mind. We noticed that the problem of designing 'food-ready' robotic automation solutions is still open. With these new blog series we will give you a summary of tips and tricks promoted by well-known organisations in hygienic design as EHEDG and 3-A SSI.  

Risk analysis

When designing robot systems for food, the first step is to complete a comprehensive risk assessment to understand the risks of contamination by the equipment. It is a team approach. Multiple skills and capabilities are required to determine what is right for specific manufacturing process and associated risks. When ensuring a machine’s design is hygienic, all the risks must be taken into account, and action (new design, new specification of sanitation measures, clarifying information for the intended use) must be taken to prevent or reduce these risks. Each part, assembly, disassembly, adjustments, systems monitoring, sanitation and so forth needs to be considered, evaluated and included in a comprehensive written project assessment and execution manual.

Food contamination happens when food are corrupted with another substance. These risks can be categorised as:

  • Physical hazards: rust particles, paint particles, foreign bodies from the equipment such as lost nuts and bolts, plastic pieces, glass particles and pieces of worn out elastomers.

(Source: ABI & IDPartners)
Example of physical hazard : loss of springs

  • Biologcal hazards: pathogens, viruses, mould, parasites.
    For example, the end-effector/tool should not introduce any risk of contamination of the product.

(Source: Dewilde Engineering)
Example of prevention of a biological hazard : intermediate cleaning and disinfection of tools after several cycles

Suction grippers are vulnerable in this respect since they rely on air flowing into the gripper. There is a risk to collect organic on the suction cup surface, but also in the suction device. While the surface can be easily washed, it can be difficult to clean the inside of the ejector or vacuum pump.

Gripping principle based on Coanda effect reduces the risk because organic residues will be collected on the washable suction cup surface but not in the ejector.

(Source: Schmalz)
Flow gripper SCG based on Coanda’s principle

  • Chemical hazards: cross-contaminations due to lubricants, hydraulic fluids, paint particles, residues from cleaning chemicals or disinfectants.
    For example, components using machinery fluids shall be effectively shielded to prevent ingress of fluids into the product or onto product contact surfaces, but should one occur, the use of food-grade machinery fluids can mitigate potential contamination.

(Source: Yaskawa/Motoman MPP3 (links), FANUC M-430iA/2F (rechts)
Robots using NSF-H1 certified food-grade grease

Want to know more? Stay informed!

When implementing and qualifying a robotic palletizer project, the expectation is low that the safety of edible product will be compromised. However, projects that involve the design and implementation of systems wherein picking, dosing, filling, sealing, etc. involves a comestible and its contact packaging, design criteria must be based on an assumption that various hazards will compromise product quality if not anticipated, identified, discussed, documented, mitigated or eliminated. The team of Sirris experts can support you. So be sure to keep an eye on this series of articles. Any questions? Please contact us!

Part 3 of our blog series will outline the key principles of hygienic design of robot systems.