On the Damage of Confectionery Caused by Insect Pests in Kagawa Prefecture

Abstract

In order to clarify the actual state of the damage of confectionery caused by insect pests in Kagawa Prefecture, present research was carried out in the period from 1967 to 1970 and acquired the following results:
The insect pests injurious to confectionery were about 34 species, mainly belonging to Coleoptera and Lepidoptera which are known as the eminent cerial pests. However, the 2 species, namely, the saw-toothed grain beetle, Oryzaephilus surinamensis and the Indian meal moth, Piodia interpunctella were especially injurious like in other districts. The former usually had 4 generations a year and the latter had 3 generations. The peak of appearance of the adult of the former fell on the season from June to August and that of the latter was from the middle of July to the beginning of August in general. Most of the insect pests injurious to the products were frequently observed in the local factories of confectionery, therefore, there are some problems that should be considered. On the other hand, at some local shops of confectionery and groceries, these insect pests were also observed, and their activities were remarkable during the season from July to September. From these actual status, the problems relating to the management of treatment of confectionery at the shops were also pointed out. Moreover, under such status, the damage of confectionery caused by these insect pests apparently increases with the lapse of time after the display of goods on the shop-shelves. Generally speaking, chocolates and biscuits which were prepared by large manufacturers scarcely suffer from the damage by these insect pests in the process of manufacturing, however, they frequently suffer from injury of various pests in the process of circulation of goods after coming out from factories. It is clear that the damage was closely connected with the way of packing or the packing materials, though the damage of these confectionery was comparatively great in summer season and the 2 species of insects already mentioned were also very injurious. The damage of chocolates mixed with almonds, nuts, or raisins was especially greater than other kind in general. The damage of confectionery caused by insect pests seems clearly to have come from the irrational management or treatment of goods on the shelves and the wholesale stores at which the withdrawn goods were held together with the new ones even if a short time. And these status seem to have been the important problem previous to the controlling pests by chemicals at present. Accordingly, the measure of control of pests should be at first set forth from the step of full guidance for the insect pests to traders concerned, and the chemical control of these pests should be considered in the next step and be used only in the particular case.