With the threat of contamination from harmful pathogens such as salmonella, listeria, and E. coli a continual concern, animal feed processors are seeking to protect not only the public but also their companies’ bottom lines from the massive costs, reputational damage and greater regulatory scrutiny associated with recalls. The goal is a safe, clean, sanitized working environment.
According to the FDA’s Food Safety Modernization Act (FSMA) Final Rule for Preventive Controls for Animal Food, “Every facility that produces animal food with a hazard requiring a preventive control must have a recall plan.”
Written safety plan
The FSMA Final Rule for Preventive Controls for Animal Food has various key requirements. Among these, covered facilities must establish and implement a food safety system that includes an analysis of hazards and, if necessary, risk-based preventive controls.
The rule sets requirements for a written food safety plan that includes details about the facility’s hazard analysis and resulting preventive controls.
Given the increasing number of outbreaks and recalls traced to post-processing contamination of feed, it is no surprise that the Preventive Controls Rule requires manufacturers to implement a safety plan with the goal of preventing sanitation deficiencies.
The rule covers sanitation practices for food-contact surfaces, preventing microbial and chemical cross-contamination, and monitoring potential environmental pathogens for critical equipment like conveyors.
Sanitary conveyors necessary
As a result, quality assurance teams are paying more attention to the type and design of conveyance systems used to help meet feed processor safety standards. This includes identifying potential harborage points where debris and pathogens can collect, as well as implementing best practices to save on costs to clean equipment, perform regular testing, and maintain the environment.
“Every day we are asked for recommendations about the sanitary design of equipment,” says Justin Kerr, founder of Factor IV Solutions, LLC, a food safety consulting firm that has worked with hundreds of food processors and harvesting operations throughout North America.
“With conveyors, ideally there should be minimal harborage points, they should protect products from the environment, and be easy to clean.”
Kerr says Factor IV Solutions assists food processors to develop Sanitation SOPs (SSOP: Sanitation Standard Operating Procedures) related to conveyors that include regular verification testing of food contact and non-food contact surfaces.
Given the risks of contamination, the potential for recalls, and the additional costs associated with regular cleaning and testing, however, it’s advisable to select a conveyor that eliminates many of the potential risk factors.
Selecting a conveyor system for animal feed production
In the animal feed production industry, open conveyor systems like bucket elevators and belt conveyors can be more vulnerable to contamination.
With open systems, products can be exposed to pathogens, contaminants, or moisture in the surrounding environment. Product can also spill onto the plant floor and make its way into drains. Consequently, processors that use such conveyors must maintain strict environmental controls including constant swabbing, testing and quality assurance.
Closed conveyor systems, on the other hand, effectively seal off products from the outside environment. Even then, it is still necessary to control the environment.
Although there are several types of closed systems, one example when conveying high-value foods is tubular drag cable conveyors. These systems gently move products that are prone to breaking or crumbling through a sealed tube using a coated, flexible stainless-steel drag cable pulled through on a loop.
Solid circular discs (flights) are attached to the cable, which push the product through the tube without using air. The coated cable ensures that no debris accumulates within the strands of the cable, as the cable is totally sealed.
“An enclosed conveyor like Cablevey provides a controlled environment that reduces the risk of exposure to contaminants and pathogens from outside the system when properly maintained,” says Kerr. “Because it is closed, it is less susceptible to aerosols and over spray from adjacent lines.”
Oskaloosa, Iowa-based Cablevey Conveyors is a specialty conveyor company that has designed, engineered, and serviced enclosed cable and disc tube conveyors for 50 year. The company’s product can be as small as powdered material or as large as whole potatoes, and is increasingly used to convey pet food, coffee, cereal, nuts, produce and specialty foods.
“When we conducted trials and verification testing, we found that tubular cable conveyors maintain greater repeatability cleanliness over a longer period of time than open systems due to the controlled environment within the enclosure,” says Kerr.
Additionally, Kerr notes that closed conveyors significantly reduce potential harborage points for contamination.
“Tubular drag cable conveyors are very simple in construction, without standard joints, threaded bolts, and plastic-to-metal connections,” says Kerr.
"Wet cleaning" process
Kerr points out another advantage: the enclosed conveyors also enable a “wet cleaning” process without wetting the surrounding areas, in which the systems can be quickly and effectively flooded with water and sanitized without disassembly.
While not all feed processor materials are suited to wet cleaning, such as hygroscopic materials that readily absorb and retain moisture, the process minimizes potential contamination for other types of food.
The wet cleaning procedure begins with a water rinse followed by foaming agent, a sanitizing rinse, and a final water rinse. Once the system is thoroughly flushed out, drying is achieved by attaching urethane wipers to the tubular conveyor’s discs, which act like a “squeegee” to remove any residual water.
“Within the tubular system, all wash factors can be repeatably controlled – water chemistry, temperature, physical action, and time – so every surface is equally cleaned,” says Kerr. He notes that clear tubes are available that offer the additional benefit of visual inspection or verification.
Since a complete and thorough cleaning can be accomplished without disassembly of the system, the entire process only takes 20 to 90 minutes, depending upon the layout, product and desired level of cleanliness. This can substantially reduce disruptions and downtime during production changeovers and eliminate the need for additional dedicated conveyor lines. Regular cleaning can be automated through the plant’s distributed control system.
“A benefit of Cablevey is the repeatability and verification of surfaces cleaned and the ease of maintaining them,” says Kerr. “You can do verifications against cleanliness and hold [the cleanliness] over a greater period of time.”
Quality assurance before purchase
When an animal feed processor wants to ensure that a conveyor will meet its sanitation requirements, equipment suppliers often allow quality assurance teams to perform tests prior to purchase.
“Sometimes customers come to our test lab so they can run product and conduct swab tests before and after wet cleaning and review the results for themselves,” says Morgan Bailey, communication specialist at Cablevey Conveyors.
In the feed processor industry, the stakes are high when it comes to preventing safety issues. With the threat of contamination from harmful pathogens always a concern, processors are seeking to protect both the public and their companies’ bottom lines from the massive costs associated with recalls. As a result, quality assurance teams are analyzing the type and design of conveyance systems more closely.
Enclosed conveyors that are capable of automated wet cleaning can help mitigate risk and prevent many safety issues. These conveyors provide an extra level of protection by keeping debris and pathogens from collecting.
They also save on costs by eliminating the need for manual cleaning. As processors continue to seek ways to improve safety, enclosed conveyors will become an increasingly popular choice.
Author Del Williams is a technical writer who lives in Torrance, California.