Controlling the Pest Problem At Food and Beverage Manufacturing Plants

A food illness outbreak may not shut down a plant, but woe to the processor who fails to maintain a rigorous pest control program.

By Kevin T. Higgins, Managing Editor

2 of 3 1 | 2 | 3 View on one page

USDA’s Food Safety and Inspection Service already had that authority, although the agency often is slow to exercise it. A March 2013 salmonella outbreak that sickened more than 400 individuals is an example. The antibiotic resistant strain was tied to three Foster Farms poultry facilities, two in Fresno and one in Livingston, Calif. That touched off a series of inspections. However, no product recalls or disciplinary actions initially were taken.

But noncompliance citations were issued in September, November and December of last year when inspectors observed cockroaches in the Livingston facility. When live roaches were seen on a poultry handling tub and a sink adjacent to a production line Jan. 8 of this year, a suspension notices was issued. “Poorly maintained facilities and equipment that are not maintained to prevent entrance of pests, such as cockroaches, rats and flies, can and do harbor food borne pathogens,” the shutdown notice stated. The plant reopened briefly before Foster Farms voluntarily suspended operations while it implemented new safety measures.

Suspension of a facility’s registration occurs infrequently, but processors are remiss if they don’t respond to failures in a prerequisite program. Fumigation — pest control’s nuclear option — should be part of the Livingston prescription, but prevention should be the main focus. How the cockroaches are entering the building, where they are breeding, what their food sources are and where the failures in standard sanitary practices exist are among the questions that need to be answered. Once remediation is done, a comprehensive IPM program with buy-in from maintenance, sanitation, food safety and pest control personnel can prevent a reoccurrence.

Methyl bromide used to be the fumigant of choice, although its availability is extremely limited (dirty little secret: a black market feeds illegal applications). Phosphine is the go-to option, but it is very corrosive and can cause serious problems with electrical components, copper pipes and other materials, and some target pests are developing immunity. Carbon dioxide and sulfuryl fluoride, sometimes combined with heat, are options, but fumigation as an IPM action tool occurs infrequently in processing facilities.

“Nobody fumigates three or four times a year anymore,” observes IFC’s Heath, and some processors with rigorous control programs have done away with fumigation entirely. When it is necessary, “many food companies have a protocol to use an insect growth regulator (IGR)” in conjunction with the pesticide, adds Tim Larson, Rentokil’s quality assurance manager.

Companies typically establish threshold levels for acceptable intrusions, such as the number of flying insects in a light trap. If that level is exceeded, remediation is done and a follow-up review determines the effectiveness of the corrective action. “In a bakery, you are going to have Indian meal moths, you are going to have flour beetles,” Orkin’s Siddiqi points out. “You have to establish what is acceptable and then react if that level is exceeded.”

Rodenticides are falling out of favor in IPM circles, partly out of environmental stewardship concerns but also because a trap provides more information about invasive mammals than poison.

Bio-based tactics

Some entomologists suggest processing plants are approaching near-zero tolerance for pests, although the term IPM was created partly to avoid suggesting that pest control results in pest elimination. Rodents and insects are inevitable when grain is stored. While IPM professionals point to the continuous improvement emphasis in GFSI standards as an indication that adulteration levels are shrinking, FDA’s defect action levels have not been adjusted. Those levels are determined by sampling.

In the case of wheat, there cannot be more than 32 insect-damaged kernels per 100 grams; beyond that, the wheat might be acceptable for animal feed but not human consumption. An estimated 1-2 percent of U.S. stored grains is destroyed each year by pest contamination.

The hit-list for pests at a grain elevator or storage bin is short compared to the buffet line that forms once grain is milled. Cleaning procedures filter out much of the insect parts that may be present, but live creatures now must be kept in check. “Documentation is a strong part of third-party audit requirements,” McCloud Services’ Hottel points out, and effective IPM is based on scrupulous records.

Pupae adults

Pupae and adult lesser grain borers inside rice kernels are seen in this digital X-ray image from USDA. Infestations in raw materials are frequent sources of in-plant pest problems.

Grain elevators and storage operations are the front line in the war against pests. They also are the incubators of new technical weapons and control strategies. A handful of entomologists specializing in stored grain protection are developing biologically based controls to deliver products free of insects and insecticide residues.

Bio-based solutions usually cost more, allows Thomas Phillips, professor of entomology at Kansas State University in Manhattan, Kan., but the payback from protection also is increasing. “Grain prices have gone up dramatically in the last eight years,” notes Phillips. “Farmers are buying new trucks for the family.”

Insect growth regulators that prevent a species from reaching maturity and procreating have been used successfully for 40 years in stored grain, but they are not popular in bakeries, dry cheese storage and other food production settings because people associate dead insects with effectiveness. Pheromones, on the other hand, have emerged as a popular procreation disrupter. Pheromones have been identified for almost 40 species, but only half of them are commercially produced.

2 of 3 1 | 2 | 3 View on one page
Show Comments
Hide Comments

Join the discussion

We welcome your thoughtful comments.
All comments will display your user name.

Want to participate in the discussion?

Register for free

Log in for complete access.


No one has commented on this page yet.

RSS feed for comments on this page | RSS feed for all comments