Conquering Pests in Commercial Kitchens

If German cockroaches could speak, none of us would be surprised to overhear them waxing poetic about the paradise we know as the commercial kitchen. This environment has all the makings of the good life for these pests – food, moisture, heat and harborage. It’s a place where, if left unchecked, cockroaches could theoretically eat, drink and proliferate without end.

If German cockroaches could speak, none of us would be surprised to overhear them waxing poetic about the paradise we know as the commercial kitchen. This environment has all the makings of the good life for these pests – food, moisture, heat and harborage. It’s a place where, if left unchecked, cockroaches could theoretically eat, drink and proliferate without end. 
Of course, these uninvited tenants aren’t typically alone in their stainless-steel Shangri-la. The commercial kitchen can become home to not only German, American, brown-banded and Oriental cockroaches but also a variety of small fly species, rodents and ants. Here’s where to find these pests and how to take control. 
Inspection Tips and Hot Spots
As you set out to inspect a commercial kitchen, arm yourself with a powerful flashlight, an inspection mirror and every bit of knowledge and experience you have related to kitchen pests. Gaining control over pest populations begins with locating their source; having an intuitive sense for where they might be getting in will make your search easier.  
Start with an investigative conversation with your customer. Find out everything you can about the type of pests they’re seeing and where the activity is focused. Then take a good look around. Although every kitchen is different, here are areas you should always inspect thoroughly:
• Wet places. Water is the main draw for any pest, so inspect sinks (including under the lip), dishwashers, pipes, cooler and refrigerator doors, ice machine lids and other areas of water pooling and condensation. Pay special attention to drains and wet floor mats, which tend to become breeding grounds for small flies. “If you suspect that a drain might be the source of phorid flies but you don’t actually see them in the general area, try bagging the drain to get a better look,” says Mark Sheperdigian, vice president of Technical Services at Rose Pest Solutions. 
• Areas where food debris accumulates. Organic matter collects just about everywhere in a commercial kitchen, particularly when operators aren’t as fastidious about sanitation as they could be. Look in the obvious areas – where food is stored, prepared and served, and where trash is discarded – but also in less conspicuous places. “Put your head right on the floor so you can see the underside of equipment,” says Jim Sargent, director of Technical Support and Regulatory Compliance at Copesan. “Essentially, you are looking for garbage that’s difficult to reach – organic matter that’s been missed during the cleaning process.”
• Storage rooms. Cardboard boxes and other clutter provide harborage for roaches, rodents and ants. Some of these pests actually hitchhike in with food and other supplies, and then just make the storeroom their home. 
• Heat sources. If a piece of equipment generates heat, pests will gravitate toward it. Look behind and under dishwashers, stoves, refrigerators, freezers and coolers. Pay especially close attention to the motor housings at the bottom, where heat is generated and condensation can take place. 
• Cracks and holes. Look for any structural weaknesses that might offer pests access to the kitchen: cracks and holes in the wall or around pipes, gaps around electrical outlet boxes or wall fixtures, etc. Sheperdigian recommends also checking for cracks in the floor tile or worn-away grout. “Even slight water seepage through the floor can attract vinegar flies,” he says. 
• Outdoors. Inspect the exterior of the building for spots where rodents or insects might be getting in and to examine the path from the back door to the dumpster to determine whether trash-disposal practices are sound. 
Be thorough in your inspection. “Pull out panels. Take off plates. Take coffee and cold-beverage machines apart so you can inspect them thoroughly. You may even have to take some structures, like salad or hot food bars, apart, to get a good look inside,” advises veteran PMP Stoy Hedges, owner, Stoy Pest Consulting. “Identifying the source is the first step in effective treatment.”
Remember that monitors and monitoring blocks can be a great tool for helping you pinpoint roach and rodent activity. Placing monitors in hard-to-inspect areas can tell you where you should be treating or where you need to spend more time.
Treatment Options
The commercial kitchen is a complex environment requiring an integrated treatment program. “Your treatment strategy depends on the types of pests, the level of infestation, the condition of the kitchen and a variety of other factors, from weather conditions to the type of business that sits next-door,” says Sargent. “Once you’ve identified the issues, you can make appropriate recommendations.” 
These recommendations might include any combination of the following:
Moisture elimination. Show your customer leaky pipes, drainage issues and other sources of excess water, and recommend remediation measures. Educate your customer, too, about monitoring areas susceptible to water pooling or condensation.
• Sanitation. Sanitation measures are pivotal to effective pest management. This includes cleaning up food debris and other garbage; scrubbing around drains, equipment, prep and holding areas, and splashboards; and making sure that your customer understands the critical nature of ongoing sanitation efforts.
• Harborage denial. You can’t just start throwing boxes and other clutter into the trash, but you can make your customer aware that the clutter has to go. Tell them to focus on older boxes first, where pest activity is most likely. 
• Exclusion. Put measures into place to stop pests from getting into the kitchen. Seal every crack, hole or gap you can, and make recommendations of where more involved repairs should be made.
• Vacuuming. For cockroach infestations, Hedges encourages PMPs to enlist the aid of vac packs. “While bait can be very effective, most customers don’t want to wait for it to make its way through the entire population,” he explains. “Use some flushing agent or hot air to chase them out of hiding, then vacuum as many as possible. Then you can treat cracks or voids with bait, dust or a residual aerosol, or a combination of these, to eliminate the pests at their source.” 
• Microbial products. Commercial kitchens struggling with small fly infestations are likely to benefit from bioremediation foams, gels, liquids or mists. The bacteria or enzymes in these products essentially “eat” the grease and gunk that make drains such an attractive breeding ground for small flies.
• Insecticides. Choosing the right mix of insecticides is an art mastered through experience and product knowledge. Baits tend to be the first choice among PMPs for cockroach management, but Gary Bennett, director of the Center for Urban and Industrial Pest Management at Purdue University, cautions against sole reliance on baits: “The best policy is to use a variety of baits, sprays and dusts. Used too often, baits can lose their effectiveness. They also have application limitations. PMPs are relearning the art of applying dust as they recognize its usefulness in wall voids and other areas baits and sprays can’t reach. You need the right mix to do a complete job.” Insect growth regulators, which affect the metabolic processes of insects, are another valuable tool for controlling a number of pests encountered in commercial kitchens, including German cockroaches. There are two types of IGRs used in the pest management industry: Juvenile hormone analogues and chitin synthesis inhibitors. Both groups of IGRs exhibit low toxicity to mammals, fish and other non-target species, but are very effective against cockroaches and other labeled pests. With recent enhancements to “natural” insecticides, this new technology is being used in commercial kitchens and other sensitive locations. Whenever using insecticides, always remember the Label is the Law! 
Ants are usually easy to control with baits as long as you accommodate their finicky eating habits: First identify whether the ants are drawn to proteins, carbohydrates or lipids, and then determine which bait matrix will fulfill their current needs. 
Insecticides for small flies are generally used once the breeding source has been eliminated. “Fogging never solves a small fly problem, but it can be useful for killing off the remaining active adults once the breeding site has been cleaned out with microbial products,” says Sheperdigian. 
• Traps. The prospect of dead mice or rats in the wall of a foodservice operation is not a pleasant one. Nor is the potential for food contamination due to rodents’ transferring tracking powder to food prep areas. That’s why most PMPs choose snap-traps or multiple-catch traps over rodenticides in the vast majority of commercial accounts. Tamper-resistant, weatherproof bait stations are certainly appropriate for outdoor use, however, near the dumpster, loading areas and entrances to the building.
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