Moths in groceries

Moths (e.g. Mediterranean flour moth and Indian meal moth) are, above all, pests in groceries! Other kind of moths e.g. Warehouse moth (Ephestia elutella) and Tropical warehouse moth (Ephestia/Cadra caudella) have also been located in Finland, but very seldom they do considerable damage here.

Mediterranean flour moth (Ephestia kühniella) is one of the worst and most persistent pests, especially in the mills and bakeries. In households, most damage are caused by its larvae, which can be found from the bakery products. Some damage are also done by the adult butterflies flying in the air. People easily tend to think those adult butterflies are Wedding clothes moths.

Larva of the Mediterranean flour moth lives especially in mills and bakeries and in there, above all, in the wheat flour. It has also been located in other bakery products, though never in grains. Larva weaves cobweb, which causes the flour to get lumpy. That lumpy mass also contains a lot of dark excrements. Adult butterfly does not eat much. At night time it flies around, but in day time, it just sits somewhere in the dark and shady places with its wings closed. Mediterranean flour moth withstands the frost quite well, for a short time of up to -15°C.

Indian meal moth (Plodia interpunctella) causes mostly hygienic harm by soaking the dry products with their feces.

Indian meal moth is a real pest especially in the dry fruit production of warm countries. It has spread to Finland along with the imported goods e.g. dried fruits, almonds, nuts and sweets. Its larva weaves white-coloured cobweb into which they also defecate. Adult larva wanders quite far from its birth site. There it encloses itself in a some gap. Indian meal moth cannot cope normal Finnish winter in the cold storage facilities.