Things you should note
There are a number of stored food product moth active in the UK, to name a few, Indean Meal Moth (Plodia interpunctella), Mediterranean Flour Moth (Ephestia kuehniella), Warehouse Moth (Ephestia elutella)
Mostly imported from natural food stores, less commonly supermarkets. The moth do not cause any damage, it is the larval stage that attacks foodstuffs.

Foods commonly infested include:
Whole or cracked grains (rice)
Flour, meal, or similar ground grain products
Spices
Cereals
Pasta
Powdered milk
Nuts (whole or pieces)

Eradicating food product moth is not the simplest job you could tackle, in most cases you will be using chemicals that you do not want having contact with your food.

Initial drastic action may be required unless you are happy to freeze your cereal, nut and grain products. The alternative drastic action is to destroy all dry foods from your larder. We will assume the latter is not your choice as it is not the end of the matter to just dispose of foodstuffs.

Freezing food products for 3 days will kill all stages of food product moth. Whilst your stored products are frozen you can concentrate on treating the food storage area be it small cupboard or larger larder.

Remove everything from the storage cupboard, if there are adjacent cupboards these also need to be emptied, even if they do not contain foodstuffs. There is a risk there could be larval stages in these cupboards and failure to include them in the treatment could nullify your efforts in the infested storage area.
Once everything out of the cupboards, you need to clean them with a damp cloth. Vacuuming all the cupboard nooks and crannies first would be benficial.
You then need to apply a residual insecticide to all cupboard sufaces. The simplest method is to use an aerosol such as Rentokil Insectrol, this will give a fine coating of insecticide on the surfaces and any insect moving around on these surfaces will soon pick up a lethal dose of the insecticide. This treatment is odourous, due to solvent based carriers, and this solvent odour will hang around in the cupboard for a good few days and may taint any unprotected food placed in the cupboard after the treatment. One can of Insectrol should treat around 6 wall cupboards twice.
An alternative product is Pro-Active C Stored Product Moth water based insecticide, which has an initial slight odour but this rapidly clears., however it is more difficult to control the water based spray to only apply a fine mist. Droplets from non aerosol products tend to be much larger and therefore it is harder to get an even, low quantity coverage, only a light spray is required.
Allow to dry and you can put your foodstuffs back, however, any dried foods, cereals, nuts etc MUST be in airtight containers. Also, when you put any frozen products back into the storage area you should also put those into airtight containers.
DO NOT PLACE ANY UNWRAPPED FOOD ONTO THE TREATED SURFACES.

After 30 days, if you used the aerosol treatment method, you need to remove the foods once again and re-treat the internal cupboard surfaces. This is due to aerosols not leaving sufficient long term protection. It is a bit of a belt and braces action but one you may feel better having done. If you use Pro-Active C the second treatment is not required.

Please also consider areas around the storage cupboard that may harbour moth larva or eggs. If it is a kitchen wall cupboard then it would be good practice to spray down the back of the cupboard as there is a chance that moths may have laid eggs in this area and it could be a source for re-infestation later if not treated with moth killer.

Where your problem does not involve food storage cupboards, treatment against food moth should be easier. We have had people storing dog biscuits in strange areas and they can become infested with stored product moth. Freeze or destroy the foodstuff, carefully clean the area where the food was stored and then spray at least a minimum 1 metre area around where it was stored. You can use Pro-Active C Stored Product Moth Killer for this.
In our Food Moth products section there is a natural dust that can be used in areas where spraying is not practical. You will also find a Power Fogger that will release an insecticide in aerosol format. This can be useful for treating large areas, however, it leaves no residual insecticidal coating and is essentially a quick knockdown method for gaining very rapid control, but the fact it leaves no residual insecticide means that any eggs or missed insects will be free to re-establish the infestation. Foggers can be useful in areas where spraying is not practical but several treatments may be required to eradicate an infestation.
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