According to the United States Department of Agriculture, more than 30,000 food and beverage processing plants across the United States employ more than 1.5 million workers.1 Each of those plants applies a wide range of processes to raw agricultural goods to produce consumable food and beverage products.
Within those processes, industrial compressed air applications have a major role. Processing plants use compressed air systems to support the sorting, cutting, shaping, and packaging of food and beverage products. Companies also use compressed air to clean containers before filling and to blow off particles while cleaning food and equipment.
Compressed air systems play a major role at most food and beverage processing facilities.
Compressed air systems used in food and beverage production plants consist of air compressors, dryers, filters, system piping, fittings, seals, air storage devices, valves, pumps, cylinders, and motors.
The systems include several moisture, oil and particulate removal stages. The different stages include water separators, absorption dryers, refrigeration dryers, oil vapor removal filters, coalescing filters, adsorption filters, dust removal filters, and sterile filters. Each of the moisture and particulate removal stages must meet or surpass Federal Drug Administration (FDA) and International Standards Organization (ISO) performance standards.2 In addition to those standards, the British Compressed Air Society (BCAS), the British Retail Consortium (BRC), and the Safe Quality Food Institute (SQF), and the Canadian Food Safety Enhancement Program (FSEP) have also issued standards or best practices for monitoring compressed air quality.3
Although system requirements vary, food and beverage processing applications employ either contact compressed air systems, non-contact high-risk compressed air systems, or non-contact compressed air systems. Contact systems place compressed air in direct contact with food products. While non-contact high-risk systems do not place compressed air in direct contact with food products, the systems create materials — such as packaging — that directly contacts food. Non-contact systems contain control valves, air motors, and equipment but do not have direct contact with food or packaging.
Hygiene in Food and Beverage Processing a Top Priority
Despite the size and complexity of the industry, a health and safety recall of a product because of the presence of contaminants or pathogens can cause nearly irreparable financial harm and damage to a company’s reputation. Harmful microbial communities can enter through raw foods, air, water, process surfaces, and the hands or clothing of plant employees. The microbes form biofilm on slicing and cutting equipment, conveyors, tanks with piping, filling and packing machines, and heat exchangers.
A 2011 survey by the Grocery Manufacturers Association described the impact of a health and safety recall on the food and beverage processing industry.4 The combination of lost sales, downtime costs, and product loss, along with the effort placed into recovering from a recall, ranged from significant to astronomical.
All this points to the vital importance of safety and hygiene for the compressed air systems used for food and beverage production. Any moisture in compressed air piping, air motors, or air compressors can promote fungus and microbial growth. Without hygienic processes in place, compressed air systems can blow microbial contaminants, oils, and other particulate matter onto food products. Food and beverage compressed air systems also require dry air; any excess moisture blown onto food products creates an opportunity for fungus or microbial growth on the food.
The safety and hygiene of compressed air systems at food and beverage processing operations is vitally important.
Regulatory Compliance Impacts Compressed Air Systems
All food and beverage processing operations must comply with food safety standards and practices contained within the FDA’s Food Safety Modernization Act (FSMA). The FSMA covers the food supply chain from raw production through preparation for consumer use and focuses on preventing foodborne illnesses. Placing the regulatory law into effect increased inspections of food processing plants, improved capabilities to detect the outbreaks of food borne illnesses and provided increased authority to order recalls of food products. In addition, the FSMA established a central database for tracking and tracing food safety information.
The FSMA Final Rule for Preventive Controls for Human Food mandates food facilities to have a safety plan in place that includes a Hazard Analysis and Critical Control Points (HACCP) plan. Risk — in this context — involves any point of contact between compressed air and food.
The HACCP plan analyzes biological, chemical, and physical hazards, describes the product, and includes risk-based preventive controls to minimize or prevent identified hazards. The preventive controls cover processes such as cooking, drying, refrigeration, filtering, freezing, pasteurizing, and acidifying foods; define methods for controlling allergen cross-contact; and describe sanitation processes. Processing plants must monitor, correct, verify, and document the application of preventive controls.5
Critical Control Points (CCPs) identify potential hazards that can occur. They also define process controls that prevent the likelihood of foodborne hazards causing illnesses, injuries, or death. After the identification of a CCP, members of the plant food safety team establish and manage critical limits that define operating conditions for the process.
Along with identifying CCPs, a HACCP plan also establishes pre-requisite programs that operationalize good hygiene practices and training programs. The HACCP plan also defines corrective actions if a system failure causes a deviation from the CCP critical limits and verification actions to ensure compliance with the food safety plan.
HACCP Plans Identify Compressed Air Systems Risks
The normal operation of a food and beverage processing compressed air system draws ambient air into the system through an intake filter. Ambient air contains moisture, dirt, particulates, oils, and other materials that can become toxic when allowed to contact food. One cubic meter of untreated compressed air contains approximately 180 million dirt particles, water, gaseous hydrocarbons, pollen, trace metals, and other pollutants.6
Untreated compressed air also carries bacteria that can easily travel through a compressed air system and gain contact with food products. Along with the possibility of directly contacting food, the bacteria carried within a compressed air system can also attach to air compressors, reservoirs, system piping, and fittings…and grow as microbial biofilm.7
Because compressed air systems may directly contact food or may contact food packaging, numerous opportunities for CCPs and pre-requisite programs may exist. For example, air-driven knives and mixing tools have direct contact with food and represent CCPs. Bagging systems have indirect contact with food products and also work as CCPs.
Managing Compressed Air System Risks
HACCP plans and CCPs link risk identification with risk management built through carefully planned designs and preventive maintenance procedures. Regulatory and industry standards for prioritizing consumer health and safety within food and beverage processing should influence design. As an example of design based on industry benchmarks, manufacturers recommend that compressed air systems have sterile filters at any location where compressed air has indirect or direct contact with food.
Another key design point involves removing moisture from the compressed air, before distribution throughout the system, with dryers.7 Moist air can promote the growth of microorganisms and fungi within the air compressors and system piping of contact and non-contact high risk compressed air systems. As the systems operate, the microbial and other contaminants can blow onto the food or packaging.8
Consistent maintenance programs consider sources of contamination and begin with the atmospheric air flowing into the input of an air compressor through an intake filter. They continue with careful inspection of air compressors and testing of piping distribution systems for the presence of contaminants, as well as monitoring of storage receivers, and taking corrective actions. Maintenance procedures also address the performance and maintenance of separators and dryers. For example, a thorough maintenance inspection should confirm that separators remove bulk liquids and that pressure dewpoints remain below the critical temperature threshold needed.
Filters in a compressed air system also serve as key maintenance points because of the need to remove particulates from the system. Those solid particulates may include bacterial spores that remain viable in dry conditions, ambient dust, pipe scale, residue from chemical cleaners, and other contaminants. An inspection may verify that coalescing filters continue to remove solid contaminants, water, and oil aerosols from compressed air according to an established threshold of 0.01 micron at ≥ 99.99% DOP (Dioctylphthalate Fog Method test) efficiency.7
Preventive maintenance also includes the regular monitoring of compressed air used for all production processes. As defined by International Standards Organization, the British Compressed Air Society, and the Safe Quality Food Institute, compressed air audits cover the analysis of particles, oils, and microbial contaminants. The BCAS Food and Beverage Grade Compressed Air Best Practice Guideline specifies that companies should test and verify the quality of compressed air that directly or indirectly contacts food products two times per year or when maintenance activities may impact air quality. 3,9
Carefully planned designs and preventive maintenance are key to managing risks associated with compressed air systems.
Ounce of Prevention Worth a Hundred Pounds of Cure
Since food processing involves human input, the probability of a recall is very real. For example, in 2016, there were 905 recalls.10 Data shows that the majority of food recalls are voluntary and are driven by “reasonable probability” that the food may be contaminated.
Let’s step back a minute from the technical information and put this topic into a language that we all understand. I have had the pleasure to tour many different types of food processing facilities in North America, and every single one of them holds food safety as their top priority. These facilities, though monitored by government inspection, are self-policing with dedicated quality control specialists. When you are processing or packaging food, do not think an ounce of prevention is worth a pound of cure. In food consumed by humans and the risk of food-borne illnesses, an ounce of prevention is worth a hundred pounds of cure.
About the Author
Brandon Brownlee, a Corporate Account Manager for Motion Industries, has been involved with Reliability Centered Maintenance for 20-plus years, and has served industry for more than 35 years. His main specialty is determining best warehousing practices to ensure inventory is stored properly for the maximum product life. In addition, Brownlee is a subject matter expert for protein conversion and wind power. For more information, visit MotionIndustries.com/compressedairbp, or click to Motion Industries’ On-site Solutions services.
About Motion Industries
With annual sales of \$6.3 billion, Motion Industries is a leading industrial parts distributor of bearings, mechanical power transmission, electrical and industrial automation, hydraulic and industrial hose, hydraulic and pneumatic components, industrial products, safety products, and material handling. Motion Industries has over 600 locations, including 15 distribution centers throughout North America, and serves more than 200,000 customers from the food and beverage, pulp and paper, iron and steel, chemical, mining and aggregate, petrochemical, automotive, semiconductor, wood and lumber, medical, and pharmaceutical industries. Motion Industries is a wholly owned subsidiary of Genuine Parts Company (NYSE: GPC). For more information, visit MotionIndustries.com.
All photos courtesy of Motion Industries.
To read more about the Food Processing industry, please visit www.airbestpractices.com/industries/food.
- “Food and Beverage Manufacturing.” United States Department of Agriculture. 2019. https://www.ers.usda.gov/topics/food-markets-prices/processing-marketing/manufacturing/
- “High Quality Compressor Air for the Food Industry.” Parker Hannifin Corporation. 2011. https://www.parker.com/literature/Finite%20Airtek%20Filtration%20Division/PDF%20Static%20Files/Food%20&%20Beverage%20Market/67214_174004425_en%20NA.pdf
- “Compressed Air in the Food and Beverage Industry.” Trace Analytics, Inc. 2012. https://www.airchecklab.com/resources/Compressed-Air-in-the-Food-and-Beverage-Industry.pdf
- “Capturing Recall Costs: Measuring and Recovering the Losses.” Grocery Managers Association. 2011. https://www.gmaonline.org/forms/store/ProductFormPublic/capturing-recall-costs
- “FSMA Final Rule for Preventive Controls for Human Food.” U.S. Food and Drug Administration. 2015. https://www.fda.gov/food/food-safety-modernization-act-fsma/fsma-final-rule-preventive-controls-human-food
- “Oil and Particulate Contamination.” Sullair.” https://www.amcompair.com/products/brochures/sullair_brochures/sulliar_filters.pdf
- Scott, Lee. “Reducing Contamination Risks of Compressed Air in Food Plants: Benchmarking Good Manufacturing Practices.” Parker Balston. November 2012. https://www.foodengineeringmag.com/ext/resources/WhitePapers/Compressed-Air-for-Food-GMPs.pdf
- Shanbhag, Nitin. Air Technology Group Hitachi America LTD. “Three Types of Food-Industry Compressed Air Systems.” Compressed Air Best Practices. http://www.hitachi-america.us/ice/wecompressair/assets/hitachi-three-types-foodindustry-compressed-air-systems.pdf
- BCAS Food and Beverage Grade Compressed Air – Best Practice Guideline. British Compressed Air Society. www.bcas.org.uk
- Ducharme, Jamie. “You’re Not Imagining It: Food Recalls Are Getting More Common. Here’s Why” Time, January 2019. https://time.com/5504355/food-recalls-more-common/