Food Moths (Plodia interpunctella) are a species of insects that belong to the order Lepidoptera of the Pyralidae family, first registered in the nineteenth century. They are widespread in almost all regions of the globe, except for Antarctica.

In some regions, other species of harmful moths have also been found in the food industry: flour moth (Ephestia kuehniella), cereal moth (Sitotroga cerealella), wheat moth (Nemapogon granella).

They have a biological cycle consisting of 4 stages: egg, larva, pupa, and adult. The larvae cause damage to food warehouses, kitchens, pantries, grain warehouses. They can damage cardboard and plastic packaging, including sealed food items. Furthermore, insects in the last larval stage can travel long distances, which makes monitoring and controlling them difficult.

Signs of food moth infestations

Detecting a food moth infestation usually happens when larvae are found on packaging/food products or even inside them. Most of the time, lumps of cloth woven by the larva can also be found.

Another sign of the infestation is the presence of moths inside kitchens, pantries, food storage spaces. Food moths are nocturnally active and are attracted to light sources, so they can be easily detected during the night, near light bulbs / LED lights, etc.

Food moths usually prefer cereal products (flour, cereals, pasta, baking mixes, biscuits), seeds, nuts, hazelnuts, dried fruits, and also sweets. However, larvae can be found hiding on canned food, spice jars, or even in unopened packages and sealed canisters. It is also recommended to check stored pet food.

Types of treatments for food moths

For the efficient control of food moths, certain measures are required before applying insecticide treatments: sanitization of the space to be treated, sanitization of cans/canisters, removal of infested food. Infested food products are to be sealed and thrown away in a trash can outside, not inside the house, to avoid the return of pests. Uninfested food will need to be sealed and stored indoors.

Glue traps for food moths

Glue traps come with a pheromone attractant, which imitates female sex pheromones, that help attract and capture males. Thus, the food moth’s natural breeding cycle is interrupted, and the population is gradually diminished and eliminated. They should be placed in areas where moth activity has been detected. Glue traps have an efficiency of up to 4-6 weeks. They need to be checked and replaced regularly.

Recommended glue traps for monitoring and control:

This type of trap contains an attractant that mimics the pheromones released by female moths. It has the role of attracting male specimens to trap them, thus controlling the activity of food moths in a certain area. They can be used both to monitor food moths and to control their numbers.

Pheromone dispensers for food moths

Specific pheromones that disrupt their natural mating behavior can be used for the control of food moths. This pheromone system is intended specifically for food processing and food manufacturing areas.

The principle of operation consists in the release of pheromones from strategically placed distributors, with the role of confusing male moth specimens. Thus, when a male moth detects the pheromone, it begins flying around in search of the female. This leads to the consumption of its energy and its death before getting to mate, resulting in female specimens laying fewer eggs. This way, the moth population gradually decreases and is eliminated. The system also provides permanent protection against expanding moth populations.

UV light traps for food moths

The principle these traps function on consists in attracting moths with the help of UV light and trapping them. It is recommended to use traps with glue plates against food moths. The UV light will attract pests, and they will remain trapped on the sticky surface. It provides the advantage that insects cannot escape from the device and does not make noises when they are caught. Therefore, they are mostly recommended for indoor use in the food industry. It is important to replace the board periodically, because, over time, the properties of the glue are reduced (being covered by insects or dust).

The efficiency of UV light traps depends on the space in which they are placed. Thus, for optimal results, it is ideal for them to be placed as close as possible to infested areas. In addition, the light trap must be much more intense than any other present light source.

To increase efficiency they should be turned on during nighttime, given that moths are mostly nocturnal insects.

Recommended UV-Light traps for food moths:

They are electrical devices used to catch flying insects, provided with an adhesive surface or an electrical grid. Thus, the insects attracted by the light emitted by the LEDs will remain trapped on the glue. They are usually used together with chemical treatments to control insect populations.

Insecticide treatments applied by spraying

Sprayed insecticide treatments can be performed against food moths, but they only work against harmful insects that come in direct contact with the solution. The treatments are applied in the areas where the activity of moths was detected, following a thorough cleaning. It is important to spray more product in areas with cracks and crevices, where larvae can potentially hide. Insecticides must not be applied onto food, surfaces, or utensils that may come in contact with food.

The treatments can be applied with manual or motorized sprayers, depending on the size of the treated space.

In the case of larger areas (warehouses, storage areas), the solution can be applied with the help of fogging machines (cold fog). Thus, more uniform coverage of the treated space will be achieved. Using such treatment will provide both shock action and remanent protection.

Recommended insecticides for food moth control:

They are biocidal substances used for treatments against harmful moths, most of them acting on the insect’s nervous system. Most insecticides offer contact action, they come in a concentrated form that dissolves in water, according to the recommended doses. Insecticides are applied by spraying, using manual or motorized equipment, depending on the size of the treated space.

Recommended sprayers for the application of insecticides:

Sprayers are low-pressure applicators, which are used for the application of pesticides that require precise dosing. Their capacity varies depending on the type of appliance, its design, the application method (manual / motorized sprayers), and the size of the treated space. Special care must be taken when adjusting the device, as well as when performing maintenance.

Aerosol insecticides

Immediately after the sprayed treatments are performed, it is recommended to apply an aerosol-type insecticide. The released particles will irritate moths and draw them out of their hiding places to come into contact with the initially applied solution. Before using the insecticide, it is recommended to close any doors and windows, and the furniture should be arranged so that the substances can infiltrate through any cracks where insects could be hiding. Depending on the product used, it must be allowed to act for a few hours, during which time the room must remain closed, according to the recommendations on the label.

Recommended aerosol insecticides for food moth control:

Aerosol-type insecticides act by releasing the active substance in a gaseous form, thus filling the entire space to be treated and ensuring the reach of the active substance particles into hard-to-reach places. They come pre-dosed and ready to use. The released particles irritate the pests, causing them to come into contact with the previously applied insecticide, as such, in cases of pest situations that prove difficult to control, aerosol insecticides are used together with sprayed contact insecticides. For best results, the treated area must remain sealed for at least 2 hours.

Ready-to-use insecticide treatments

Ready-to-use insecticides can come in the following forms: dust, granules, liquids, and sprays. They are designed to be applied only on dry surfaces. Because they act on contact and ingestion, pests must cross the treated space. It is recommended to carefully read and follow the instructions provided on the product label.

In hard-to-reach spaces inside or underneath furniture, it is recommended to use dust insecticides. They are applied in cracks and fissures in which moth eggs can be hidden.

Ready to use insecticides for food moth control:

Ready-to-use insecticides are pre-dosed solutions and can come in several forms (spray, dust, granules, etc.). The application is made according to the treated space, taking into account the information on the product label. For optimal results, they should be applied as close as possible to the source of infestation.

Special devices can be used for the application of dust products.

Recommended dispensers for the application of dust insecticides:

Dusters are devices specially designed for the application of granular or powder (dust) products. They are used to treat hard-to-reach places, for example: inside walls (cracks), behind panels, spaces around electrical outlets, and other very narrow spaces.

Safety Equipment

To avoid inhaling vapors created during spraying and direct contact with the applied substance, it is advised to use proper safety equipment. Safety equipment has the role of protecting the person performing the pest control treatments.

Recommended safety equipment:

Safety equipment has the role of protecting the person performing the treatments from dangerous substances. This includes protective gloves, suits, masks, etc. The equipment is selected according to the type of treatment as well as the substance being used and the targeted pest.

Insecticide tapes

They are special tapes that release an insecticidal substance that eliminates moths that come into their range. They are placed in uninhabited storage spaces, out of the reach of people or animals. Not recommended for small spaces (cabinets, drawers). Once hung, the tapes can protect against pests for a long time (3-4 months).

Because food moths are particularly harmful insects to the food industry, their control mainly requires taking rigorous hygiene measures (cleaning the area and food packaging, eliminating infested food, etc.) and choosing the appropriate treatment depending on the area where moth activity was detected.