Stored product pests threaten food safety – and your bottom line

Packaging preserves food, makes it easy to handle and keeps it safe on the journey down the supply chain to the kitchen or pantry. But what if food is infested and contaminated by pests during packaging? Don’t let pests damage your bottom line—and reputation—by jeopardizing the safety of the food that passes through your facility. Stored product pests can cost you thousands of dollars in damaged products, compromise brand integrity and threaten compliance with government regulations. They contaminate more than what they eat, so even a small infestation can have big consequences.

Stored product pests can be introduced to products at any point in the supply chain, including during production, packaging and shipment. Pests can also infest the products when they are at the warehouse, at the retail establishment or in the hands of the consumer. Even if packaged, food is still vulnerable. For example, some pests are invaders and enter packaging through poorly sealed seams, “breathing pores” or tears. Others are penetrators and chew through the packaging at seams or anywhere on packaging materials that are not pest resistant.

Products contaminated by pests not only compromise the texture, color and palatability of the food but also pose health risks. Some pests carry disease-causing pathogens such as E. coli, Salmonella and Trichinae that can be fatal. The larvae of some stored product insect pests can also cause gastrointestinal irritation, especially in children, the elderly and people with compromised immune systems. Body parts, metabolic wastes and toxins produced by some pests and left in the food products can cause allergic reactions as well.

If your products are infested by pests, your facility could suffer financial loss because of contaminated food that must be thrown away or damage relationships with customers that distrust your food safety. These financial losses, as well as government regulations, could shut down operations completely. Therefore, food packaging facilities need to be proactive and establish effective pest monitoring and treatment strategies.

Knowing the pest pressures on your facility and the type of pests you are dealing with is the first step toward prevention and effective treatment. The type of pests affecting a facility will depend on the products being handled, packaged and stored, and these are some of the most common:

• Indian meal moths are attracted to dry foods. A female moth can lay between 100 and 400 eggs in her short two-week life, so an infestation can get out of hand quickly. After hatching, larvae spend time developing in the infested product, spinning webs and feeding from underneath it. When they reach the last larval stage, Indian meal moths leave the infested food source in search of a protected surface to pupate and complete their lifecycle. Typical signs of an Indian meal moth infestation include build-up of droppings (frass) in product, silk webbing in the product or around the edges of the packaging and pupal cocoons along walls, racking shelves, ceilings or close to areas where infested food product is stored. Tiny, dirty-white, maggot-like larvae (nine- to 20 mm long) can also be seen moving about in the food product;
• Beetles, including dermestid beetles, sawtoothed or merchant grain beetles, drugstore beetles, cigarette beetles, spider beetles, flour beetles and other grain beetles feed on grains, flour, processed foods, pet foods, fabric, spices, coffee, tobacco and much more. Foreign grain beetles and spider beetles are also attracted to damp and moldy grains and food products, so their presence could be a sign of poor storage conditions associated with moisture;
• Granary and rice weevils – as their name suggests – attack whole grains. Their larvae feed from the inside of the grain, leaving it hollow. This is one of the primary signs of an infestation, as well as holes from the mature weevil exiting the grain. While weevils don’t spread disease, their presence destroys the grains that they infest and breed in. Weevils also cause infested grains to heat, encouraging the growth of fungi and sprouts.

To help prevent these pests from turning into a large-scale infestation, monitoring and early detection, as well as effective sanitation and maintenance programs, are key. Here are steps you and your staff can take to help fend off stored product pests:

• Use insect resistant packaging and inspect packaging for holes, especially at the seams, to see if pests have chewed in or out of the material;
• Inspect trucks for pests before loading products for shipments and inspect incoming  loads;
• Eliminate pest entry points and harborage sites. Make sure doors and windows are closed and sealed properly;
• Caulk and seal cracks and crevices inside the building, especially along baseboards, on floors and in the base of machinery footings;
• Inspect and regularly clean hard to reach areas in the facility such as decommissioned equipment, voids, surfaces above eye-level and dead-end spaces in machineries;
• Keep product off the floors and stored on racked shelves. Address spills immediately;
• Allow proper ventilation and illumination in storage areas. Ventilation helps keep food moisture down, which discourages pests and mold growth;
• Use pheromone traps to monitor for infestations. Insect glue boards and food lures can also help monitor for crawling pests;
• Work with your pest management provider to train staff to identify the signs and help protect against a pest infestation.

Because food packaging facilities store and package a large quantity of products, pest infestations must be addressed immediately to avoid widespread damage. However, clearing away pests and sanitizing affected areas might not be enough to control the problem long-term. Canadian regulations also enforce strict guidelines for pest removal, which include detailed documentation that untrained employees may be ill-equipped to manage. To keep your reputation intact and protect your bottom line, proactively work with a pest management provider to develop a strategy that not only complies with third party audit and regulatory requirements but also helps prevent pests in the first place.

Alice Sinia, Ph.D. is quality assurance manager – Regulatory/Lab Services for Orkin Canada focusing on government regulations pertaining to the pest control industry. With more than 15 years of experience, she manages the Quality Assurance Laboratory for Orkin Canada and performs analytical entomology as well as provides technical support in pest/insect identification to branch offices and clients. For more information, e-mail Alice Sinia at asinia@orkincanada.com or visit www.orkincanada.com.