High-Performance Polymer in Food Processing Equipment
Food processing is one of the most critical industries that call for hygiene and cleaning factors, which are otherwise overlooked in areas such as automotive, chemical, or oil & gas. With the advent of automation, food processing is increasingly seeing the need for materials that are approved by bodies such as FDA and EFSA, which will not degrade in any way during the operations. These bodies have laid down certain laws, regulations, standards, and guidelines that contact materials must meet when they are used in direct contact with food. These materials of construction are usually selected based on their strength, elasticity, hardness, toughness, sensitivity to wear, corrosion and fatigue resistance, ease of fabrication, availability, and cost price.
In the construction of food processing equipment, the focus of construction material also lays on the prevention of food contamination due to microorganisms, dirt, chemicals, and physical substances, during the short period of contact between the product and equipment. There is also a contamination risk involved with the use of plastics that involves costly recalls. Therefore, some food processors will need detectable materials, which will detect plastic contamination during food preparation or processing. A few semi-crystalline FDA-compliant thermoplastics are available to detect plastic contamination in optical, metal, and X-ray detectable grades.
Benefits of Plastics against Metals
Metals, especially stainless steel, are the common material choice for processing equipment and CIP (cleaning-in-place) units. However, while stainless steel tolerates chemicals and heat, it can corrode on constant exposure to chemicals at high temperatures. Metals also need lubricants for the frictional components to operate effectively, which invite particles that could contaminate the CIP system. It is possible that the lubricants can even act as a contaminant. While heat might not develop in processing operations, it does occur during CIP operations and SIP (sanitizing-in place) systems are even hotter. Processing equipment materials need to tolerate the temperature fluctuations which is also known as dimensional stability between production (relatively lower temperature) and cleaning using steam (relatively high temperature). Again, metals are a good choice as they tolerate heat, but metals also conduct it.
Processing facilities are consistently working towards minimizing operators’ exposure to hot temperatures and caustic chemicals because high temperature (>100OC) causes problems in providing long-term durability. Plastics can have exceptional chemical and corrosion resistance and their capability to tolerate heat is exceptional. There are several other benefits of using plastics against metals, for example, they are self-lubricating which makes parts and operations cleaner and helps to reduce pollutants, thereby reducing overall maintenance time. They are lightweight and easy to assemble with reduced noise against metal-on-metal wear.
Why high-performance polymer will witness a positive outlook?
The selection of alternative materials or scalable manufacturing processes, such as plastic injection molding can reduce component costs when compared to metal machining. Metal components may require costly multi-step machining to manufacture. A high-performance polymer would provide the desired service life as it would be inert to various chemicals and have high mechanical strength, allowing minimal downtime and enhanced productivity. High-performance polymers offer additional benefits in terms of cost-effectiveness, productivity, performance for OEMs, and the neutral taste expected by consumers.
Further, ChemBizR has identified some of the mainstream food processing industries such as dairy, meat, bakery, and beverage, among others that involve the processing and production of various plastic components/equipment.
The manufacture of cheese and dairy products involves plastics in different process steps, such as separating the whey, portioning, as well as transportation, and cutting used in paddle mixers, and scrapers. High-performance polymers such as PTFE, PVDF, and PEEK, among others fulfill the requirements of high chemical resistance and offer in addition high strength as well as excellent slide friction properties even at higher temperatures. PEEK and PTFE are used as suction cup materials providing high retention force which can be used in picking eggs while processing egg products.
Meat, Fish, and Poultry Processing
A hamburger or minced meat patties undergo rigorous production of meat processing before being packed. The use of materials such as PTFE or a POM-based scraper blade helps in providing low friction and high chemical/corrosion resistance making the food production clean and hygienic. Moreover, the selection of material is done in such a way that its mechanical properties are brought to bear particularly at very high levels of production capacity utilization. Hence, the costs for maintenance and replacement are reduced to a minimum.
Other than this, the use of high-performance plastics used in guide roller and star wheel with the excellent abrasion behavior, high strength, and hardness of plastics makes them an ideal choice for machine components. PEEK offers a perfect solution where extremely high temperatures are required during the production process.
Dough manufacturing is one of the key process stages in the production of baked goods. There has been advancement in spray technology, which utilizes the use of plastics for fulfilling special attributes. The spray nozzle allows the adhesion of seeds in a bread roll production line. It is also used in the coatings of heated viscous fluids like chocolate or peanut butter. The rotary jet spray nozzle has been used in tank cleaning providing reduced coefficient of friction and enhanced chemical/ corrosion performance with the use of materials such as PTFE, PVDF, and PEEK, among others.
Belts and conveyers made up of PTFE or coated with PTFE provide the conveyer belt with good sliding properties (minimal adhesion) for processing foods such as eggs, bacon, sausage, chicken, and hamburgers. In humid atmospheres or where there is direct contact with fluid, the material with its low water absorption properties offers an ideal solution. The lightweight materials used in conveyors and slide rails help save energy and reduce maintenance costs due to low wear.
The preparation of beverages involves concentrating and filtering the selective solution via membranes. The use of high-performance materials such as PSU, and PVDF, among others offer high selectivity and broad chemical resistance for membrane filtration technology. Other processes in the beverage industry involve the reuse of empty bottles after consumption. Plastics such as PEEK and POM are ideally suited, to be used as bottle holders and grippers.
The use of plastic against metals improves performances involving chemical/corrosion and frictional attributes, further accounting for lower production costs. Therefore, the use of certified high-performance plastics will see significant growth, higher than the food processing industry.