The top 3 pests in food processing

Pest infestations cost time and money, damaging stock, disrupting operations and posing major threats to health, safety and sanitary compliance. So, it is worth being prepared against the biggest pest threats to your food processing business.

We worked with the Centre for Economics and Business Research (Cebr) to survey 1,000 companies in five countries to find out the impact that these pests have on food processing businesses.

We discovered that the three most damaging pests from a cost and brand reputation point of view were stored product insects, rats and flies. Each one of these pests can affect your business in their own way, resulting in multiple negative outcomes and challenges for you to face.

Stored product insects (SPIs): One of the most expensive pests

Stored Product Insects (SPIs) is a generic term that covers beetles, weevils, moths and mites infesting food in storage anywhere in the food chain from the farm to the kitchen. Our survey found that they are the most expensive problem, with the most significant impact on revenue.

Businesses were also concerned about the damage these cause to finished goods and raw materials. 60% of businesses reported annual revenue losses of 1–9% as a result of SPI infestation, while 73% reported feeling highly or moderately concerned about income loss.

Stored product pests are most likely to be in a food ingredient on delivery to a processing factory or a processed food product when stored for a long time. Most dried food products are susceptible to pests, including cereal products, seeds, nuts, dried fruit, spices, powdered milk, tea and preserved meats. All stages of the pest can be present simultaneously — egg, larva, pupa, adult.

They can also enter packaging made of paper, cardboard, plastic, cellophane and foil. The entrance holes of some insect are smaller than can be seen by the human eye, so there may be no visible damage to packaging containing pests.

Stored product insect control

Stored product insect pests are controlled by using standard quality-control measures throughout the supply chain, such as fumigation and food hygiene practices, for managing suppliers, logistics companies, incoming shipments, storage of raw materials, processing, packaging and storage of final product. Infestations are not obvious to the untrained eye. Therefore, staff should be trained to look out for the signs of stored product pests:

• Damaged products, such as small holes in nuts or grain
• Live or dead insects (small beetles and moths), larvae, pupae or silken webbing on food storage bins
• Infestation, holes, larvae or webbing on the outside of packets or sacks/bags of raw materials
• Larvae, pupae or silken webbing in cracks and crevices around shelves or on machinery, in food spillages, on beams and window sills
• Pests caught in insects traps

Flies: One of the most disruptive pests

Flies: One of the most disruptive pests

A number of fly species are attracted to the odours present around food processing plants, such as fruit flies, drain flies, and filth flies — which includes house flies. Different fly species are attracted to different food products, including fermenting sugars, oils and fats, carbohydrates, and decaying proteins and vegetable matter.

Flies can transmit up to 200 pathogens that cause diseases in humans or spoilt food, including: Salmonella, Campylobacter, E. coli, Cryptosporidium, parasitic worms, and fungi.

The habits of flies bring them into contact with many types of filth such as faecal matter, garbage, rotting materials, as well as stored and processed foods in food processing plants. They regularly move between the contaminated food sources and clean areas, carrying filth on their bodies and microorganisms internally. House flies regurgitate digestive juices and defecate while feeding and resting, contaminating foods and surfaces.

Our survey found that flies are some of the most disruptive pests. Fly infestations are the most likely to cause staff absences through illness (11%) and a single infestation can lead to over nine working days lost in a year.

Fly control

Fly control practices, including fly extermination, fly pest control, and commercial fly control, are crucial for maintaining proper hygiene standards. The application of standard food hygiene practices is particularly important for controlling flies to reduce the attractive odours, feeding material, and breeding sites. They can also be controlled by installing barriers and insect light traps to prevent access and catch those that enter a building:

• Use of screens on windows and vents, maintained in good condition
• Appropriate door designed for the purpose, for example, automatic doors, air curtains, roll-up doors, vinyl strip doors
• Doors are kept shut when not in use
• The building is maintained to prevent gaps appearing in any part of the building fabric that would allow insects to enter UV light traps and pheromone traps can be used to trap flies to help prevent the build-up of breeding populations
• Effective fly control measures, including commercial fly control, play a significant role in maintaining the hygiene and safety of food processing facilities.

Rats: One of the most destructive pests

Rats are attracted by food supplies and do not venture far from their shelter or nesting sites, so, in a large facility, they will nest close to accessible food supplies. They can grow in numbers quickly with an abundant food supply due to the number of litters they are capable of producing and the short time to maturity, shelter from predators and benign environmental conditions inside a building.

Rats are some of the most destructive pest, according to the Rentokil survey. Over a quarter of businesses surveyed reported damage to electrical equipment from rats. As a consequence, they are also the most likely pest to cause production downtime, with businesses losing an average of eight working days a year due to rat infestations.

Rats also spread urine, droppings, and filth picked up from the environment, wherever they run, damage food containers and packaging by gnawing, and eat any food they can access. They can transmit a large number of diseases, including salmonellosis, leptospirosis, toxoplasmosis, Lyme disease and rat-bite fever. They also carry parasites, including ticks, fleas, lice and mites.

Rat control

Control of rats involves the elimination of harbourage in and around buildings and preventing access to food, water and shelter. There may be many points of entry to a building, such as cracks, vents, pipes, cabling, drains, doorways, windows and screens, where building maintenance measures can be taken to prevent access.

It’s important to recognise the signs of rats as they are unlikely to be seen during daytime. This is best done by a trained professional who has the expertise and tools to identify entry points, places of harbourage and routes of travel around a building. This is an essential step for planning control and prevention measures. The information gathered will enable our technicians to identify the most suitable places to install our PestConnect digital rodent control solutions. The common signs of rats are as follows.

• Droppings along their runs and near a food supply
• Sightings of live or dead animals
• Noises such as squeaks, gnawing sounds, scurrying sounds
• Smudge marks along runs caused by their oily fur
• Tracks in dust or powder laid on the floor
• Gnaw marks on food and packaging or wiring
• Urine stains detected using UV light