In the never-ending struggle to keep food safe and microbes at bay, the operation sometimes is a success but the patient dies. Such was the case with Hot Mama’s Foods.
Hot Mama’s had tapped into a bull market for its private label hummus, salsa and dips. In 2013, the two-plant processor racked up sales of $33.3 million, a 15 percent increase from the previous year. Four-fifths of sales were to Trader Joe’s and Target, which marketed the products under its Archer Farms name.
Demand was so strong that Hot Mama’s outgrew its Elk Grove Village, Ill., plant and leased 68,000 sq. ft. in nearby Wheeling, Ill., another Chicago suburb, in a facility that formerly housed an Orval Kent Food Co. commissary. A few months later, disaster struck in the form of a May 2014 recall involving Listeria monocytogenes, quickly followed by a second Listeria recall when a test-and-hold procedure was violated.
Hot Mama’s suspended operations while CBRE Chicago, a real estate management firm, brought in James Marsden, a professor of food safety and security at Kansas State University, to address the contamination issue. In a white paper published by the college's Food Science Institute, Marsden notes that, although “the plant and equipment had been cleaned and sanitized using pre-existing protocols and chemicals,” swab tests were positive for Listeria on two pieces of equipment and in a drain.
In cooperation with FDA, Marsden developed a remediation plan involving ozone gas and silver dihydrogen citrate (SDC), a disinfectant and food contact-surface sanitizer approved by the EPA a few years ago.
An extremely powerful oxidizer, ozone was first used in the early 20th Century for wastewater treatment, but it was not until 2001 that FDA cleared its use in food contact. Several makers of ozone generators, many with roots in pool water sanitization, have targeted the food industry since, with limited success. If the concentration of ozone in an aqueous state is too high, degradation of seals and gaskets and even pitting of stainless steel can occur. Worker health concerns due to outgassing and ozone’s instability also have limited the technology’s adoption.
Gas-phase ozone was used to treat the plant’s air-handling equipment, followed by surface disinfection with SDC. Ozone gas also was used to decontaminate all non-food processing areas, while SDC was the remediation for the processing and packaging areas, lift trucks and other equipment.
A second microbiological mapping study was conducted to assure the contamination “was fully addressed,” Marsden wrote, and a preventative maintenance and sanitation schedule including semi-annual mapping studies was submitted to FDA and the building’s owner. Based on 300 environmental samples, he declared pathogen eradication had been successful, and “FDA issued two letters to the owners of the facility, releasing the equipment and facility for manufacturing of FDA-regulated product.”
Unfortunately for Hot Mama’s, the clean bill of health came too late. The entire Wheeling staff was laid off last July, and the company’s Massachusetts plant was subsequently sold to another food processor.
Marsden’s paper explicitly cites the vendors of both the ozone generators and the SDC-based cleaner, sanitizer and spraying and foaming equipment.
Pure Bioscience Inc. is an El Cajon, Calif., developer of the SDC technology. After developing the stabilized silver-ion complex in 2001, the firm spent the next decade seeking EPA approval for use as a hard-surface disinfectant in food plants. Since gaining EPA registration, the firm has secured GRAS designation and is seeking FDA approval for direct contact with food. “Soaker pads for poultry would be a very good application,” suggests CEO Hank Lambert.
Like ozone, antimicrobials with a silver ion base have struggled to gain food-industry acceptance. Silver ion has been used as a coating on drain traps and as an additive in epoxy and other flooring systems, with limited acceptance. Several manufacturers and installers of floors have offered it as an option, and UK-based Flowcrete has incorporated it as a standard feature. But many food processors dismiss silver ion as an added cost that doesn’t negate the need for regular cleaning and sanitizing and the removal of biofilm formation.
Medical device manufacturers embrace the technology, Lambert points out, but Pure Bioscience was on the brink of bankruptcy two years ago because management pursued multiple applications. He was part of a new board and executive management group that “strictly focused on building SDC as a food-safety solution.” It is effective in destroying bacteria, fungi and viruses, the last a microbial contaminant of rising FDA concern.
It also is the least toxic sanitizer available and has a higher efficacy than conventional sanitizers such as chlorine and quaternary ammonia. “Basically, it’s a green product, and we’ve consistently been able to show 90 percent-plus higher reduction in bacteria on surfaces,” adds Lambert. Faster kill (typically 30 seconds) and 24-hour residual protection also help justify a higher cost that he characterizes as “pennies a month.”