Survey of Italian honeys for the presence of foreign matter using the filth test.

Honey is an ancient food that has always been considered a natural and healthy product, free of contaminants. However, it can contain toxic substances, such as antibiotics, pesticides and heavy metals, as well as foreign matter (e.g. arthropod body parts and microbial contaminants), working as allergens and vectors of human pathogens. In this study we used the filth test to evaluate the abundance of foreign matter in 70 Italian honeys, including Castanea sativa, Robinia pseudoacacia and multi-floral honeys, the latter both from small beekeeping farms and industrial producers. The abundance of different foreign matter varied in honeys, with a higher number of carbon particles and other inorganic fragments, followed by fragments of animal origin. This latter included insects (Diptera Brachycera larvae and Strepsiptera), their cuticular fragments (mainly Coleoptera, Hymenoptera and Lepidoptera), mites (mainly Glycyphagidae, Acaridae and Tarsonemidae) and mammal hairs. No differences were recorded in the abundance of foreign matter among different kinds of honey, as well as between honeys from small and large-sized producers. Foreign matter found in honey provided functional information to evaluate honey quality standards in apiary, honey extraction and packaging phases. Overall, the filth test method applied to honey quality control can be considered an excellent tool, also for small beekeeping farms, since it allows rapid and frequent quality checking of the production process. This method is cheap, requires minimal instrumental equipment and results can be interpreted quickly.