Here’s a quick rundown of the types of pests you’re likely to see in kitchen settings:
Types: German (by far the most prevalent), American, Oriental
What attracts them: Food debris, grease, moisture, clutter (especially cardboard), heat
How they access the kitchen: Hitchhiking on deliveries or crawling through cracks, crevices and holes from adjoining areas or from outdoors on warm summer nights; (American and Oriental) storm drains, utility tunnels and steam tunnels; (American) sewage systems
How to treat them: Sanitation plus an integrated program including vacuuming, baits (possibly in conjunction with IGRs), dusts, aerosols and water-based residuals
Types: Phorid (humpbacked), vinegar and drain (moth) flies, fungus gnats
What attracts them: Grease, grime, moisture, organic matter
How they access the kitchen: Through sewage and drain pipes, cracks in the slab or flooring, on produce, or in from the outside
How to treat them: Locate and eliminate the breeding site. Prevent their return through sanitation of drains, equipment and trash cans/dumpsters; application of microbial foams, gels, liquids or sprays (sometimes in combination with IGRs); insecticides labeled for kitchen use
Types: House mice, Norway rats, roof rats (commercial)
What attracts them: Food, harborage
How they access the kitchen: Through holes or gaps in foundations, walls, floors, windows and dropped ceilings
How to treat them: Seal entry points, set traps inside (prebaiting is recommended) and rodenticide baits outside
Types: Odorous house, pavement and Argentine ants, plus regional species
What attracts them: Food, moisture, grease
How they access the kitchen: Trailing through even the tiniest openings from outdoors or nests situated in wall voids
How to treat them: Find and seal entry points, spray outside foundation, use baits indoors/outdoors
Stored Product (Pantry) Pests
Types: Moths and beetles such as saw-toothed grain beetles, Indian meal moths and rice weevils
What attracts them: Dry pantry and pet foods
How they access the kitchen: Hitchhiking on packages of food brought into the kitchen or flying into open windows and doors, usually found in oldest and least-used products
How to treat them: Eliminate the food source(s) responsible for the infestation, clean the pantry/cabinet, treat cracks and crevices with insecticides labeled for kitchen use
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.
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.
Given the choice of servicing a kitchen call from a single-family home or a multi-unit complex, most PMPs would choose the former. Pests in a detached residence tend to be easier to manage, because of not only the types of pests you encounter but also the relative ease with which you can control access to food, water, heat and harborage. Convincing one family to cooperate versus tenants of an entire building also makes the job simpler.
How do kitchen pests differ in detached and multi-unit residences? Most notably, cockroaches are king in multi-unit settings, while it’s unusual to find cockroaches in detached houses. You’re much more likely to find ants, stored-food pests, small flies and sometimes mice – all of which can pose problems in multi-unit accounts as well.
Inspection Tips and Hot Spots
Whether in a single-family home or a multi-unit complex, your residential kitchen inspection should begin with a conversation. Interview your customer about what they are seeing. Try to get a sense of what kind of pests you’re dealing with and how widespread the infestation might be. Then start your visual inspection. Here are some points to keep in mind:
• Look for cockroaches in kitchen cabinets (including around the hinges), around plumbing, near the sink and dishwasher, around the refrigerator (including the seal around the door), in the hoods over the stove and food-prep areas, in wall voids – anywhere they might find crumbs of food, drops of water, heat or safe harborage.
“Inspect for leaks, because moisture is the top area of concern,” advises Richard Berman, consultant and former technical director of Waltham Services. “Then, if you can, pull out the stove and refrigerator (carefully – don’t damage the floor!) to get a good look behind and under. Lie flat on your back to look up under cabinets and sinks. It makes sense to start your inspection where the customer has seen activity, but don’t limit yourself to that. Examine every crack and crevice.”
• Look for evidence of mice where you see food scraps or crumbs, and inspect cupboards for droppings. Inspect the exterior perimeter of the building for entry points and the interior walls for holes. “Maintenance workers in apartment complexes tend to neglect repairing holes left behind when drain, water supply or dishwasher lines are installed,” says Richard Kramer, CEO of Innovative Pest Management. “Apartments share these common drain systems and walls, which means rodents and cockroaches have free access from one unit to another.”
• For ant issues, find and follow the trail to the source. Closely examine the edges and corners of the pantry, cabinets, stove, baseboards, and under the sink – anywhere food or moisture might be. If you can’t find the trail through a visual inspection, try prebaiting, which can also help you identify whether these ants are more inclined to accept a protein, carbohydrate or lipid bait. Once you’ve located the trail, you should be able to determine whether the nest is situated in a wall void or outdoors.
• Locating stored-product pests – saw-toothed grain beetles or Indian meal moths, for example – entails a visual inspection of the pantry and determination of which foods are attracting them. Examine older food items first, Berman advises, as well as pet foods, since they are most frequently the culprits.
• To determine where phorid, vinegar and drain flies might be breeding, inspect all of the drains and other wet areas of the kitchen: in and around the dishwasher and sink, and anywhere condensation might be an issue.
• Don’t overlook the possibility that the infestation could be in another room. Activity in the kitchen might be just a symptom of a larger problem going on elsewhere in the residence.
Treatment begins by taking any measures you can to eliminate or minimize food, water, heat and harborage. Clean up crumbs and gunk. Locate and repair water leaks. Minimize clutter, especially cardboard and other natural materials. Seal any cracks or holes in the walls and around pipes and drain lines. Once you’ve addressed sanitation and exclusion, you can develop a treatment strategy.
• Cockroaches: Cockroach baits have become the go-to solution for many PMPs. But Kramer suggests using a combination of treatment methods, depending on the circumstances. He explains, “If the infestation is light, then baiting might be enough, but if you’re seeing 50 or more, then you know there are 500 or more in that space. Consider vacuuming those you can see, then spray and follow up with baits. Spray is a particularly good choice if the unit you’re treating is vacant, between tenants.” Where to bait? Near harborage sites: in the upper corners around the sink and dishwasher areas, along drawer tracks and places where you see fecal deposits. Keep baits out of sight, says Kramer, and remember to rotate them to minimize resistance. Kramer also recommends adding insect growth regulators (IGRs) for longer-term control.
• Mice: Don’t underestimate the power of exclusion efforts in controlling rodent activity. Beyond that, snap-traps are a great option. Kramer warns against using open rodent baits in a residence but suggests they might be effective in a utility closet that is inaccessible to children and pets.
• Ants: Unless you’re dealing with a particularly aggressive species – fire ants or crazy ants, for example – ants are generally easy to treat. Gary Bennett, director of the Center for Urban and Industrial Pest Management at Purdue University, shares this advice: “Exclusion is important, because once ants gain access, they can nest in wall voids and other places that can be difficult to identify,” he says. “Talk with the customer if you see issues with ill-fitting windows or doors, or plumbing that’s not properly sealed off.”
What to do once ants have made their way in? “Spray the foundation of the house, as well as any outdoor nests, to gain fairly quick control,” advises Kramer. “Inside, baiting is preferable to spraying. Just make sure that you explain to your customer that they will see increased activity for a few days while the bait is attracting ants. Otherwise, they will think the situation is getting worse.”
• Stored product pests: Once you have identified the pest and the food source attracting it, discarding that product is the first treatment step. “Inform the customer that any contaminated foods should be discarded, but don’t discard them yourself because they are the customer’s property,” recommends Berman. “Once the contaminated foods have been eliminated, treat cracks and crevices with insecticides labeled for kitchen use.” Customer education about sanitation and sound food-storage practices is important to preventing future infestations.
• Small flies: Microbial foams, gels or liquids clean grease and other organic matter from drains, usually solving any residential small fly issues. Insecticides labeled for kitchen use may be added if a large number of flies remain after the sanitation process is complete.
Whether in a commercial or residential account, resolving kitchen pest issues requires a collaborative effort between the PMP and customer. Your technicians can do everything right, but if your customer ignores the need for sound sanitation practices or repairs, pest problems will continue to plague the kitchen. Communication is key: Customers who are well-informed are much more likely to do their part.
With commercial customers, communicate the critical nature of staff education. Employees who understand the implications of pest issues – customer dissatisfaction, food contamination and even the potential for the establishment to be shut down – are more likely to adhere to procedures put into place to hold pests at bay.
Among residential customers, homeowners are usually very cooperative; they want their home to be pest-free for the long term. In multi-unit accounts, your conversations will be with property managers for the most part; they should then share pertinent information with tenants.
Here are some of the important areas you or your technicians should discuss with your commercial customers:
• Sanitation – In commercial kitchens, management needs to create a culture where sanitation efforts become automatic, by providing clear instruction in every area of keeping the kitchen clean. Sanitation is critical in residential kitchens, too: Residents need to understand the importance of cleaning up crumbs, spills, grease, etc.
• Exclusion – A closed-door policy is important: Open or propped doors and windows are invitations to pests.
• Clutter control – Cardboard boxes and other clutter in storage rooms and around the house serve as harborage for pests.
• Trash management – Foodservice employees need to be taught proper trash handling procedures: how to get trash from the kitchen to the dumpster, how often to take out the trash and how to keep trash receptacles clean. A cleaning schedule for trash cans and dumpsters (at least once a week) should be established to prevent small fly breeding and other infestations. Residents need to establish appropriate trash-handling routines as well.
• Inspection of incoming products/packages – Eliminating pests at the point of entry begins with an inspection of all packages that come into the kitchen. Whether bags of produce or boxes of paper towels, these packages can harbor cockroaches and other pests.
• Repairs – Your technician is likely prepared to seal cracks and small holes, but where larger repairs are needed – to walls, floors, pipes, equipment, etc. –these issues must be reported to the customer. The customer needs to understand why each repair is important to resolving their pest issues.
• Pantry storage – Residents especially need to understand the need to rotate products and limit the amount of time they keep them on the shelf. If they plan to keep products susceptible to pest contamination for any length of time, they should store them in glass or plastic containers rather than bags or boxes.