Microbiological aspects of processing and storage of edible insects

Growing pressure on the worlds’ livestock production sector and enduring protein undernourishment, persuade the search for alternative protein sources. Insects are widely consumed in many parts of the world and are evaluated as food or supplement. Nevertheless, little attention has been given to the food safety and shelf-life of food insects. An exploratory evaluation of the microbiological content of fresh, processed and stored edible insects was carried out, with focus on farmed mealworm larvae (Tenebrio molitor) and house crickets (Acheta domesticus). A short heating step was sufficient to eliminate Enterobacteriaceae, however some sporeforming bacteria will survive in cooked insects. Simple preservation methods such as drying/acidifying without use of a refrigerator were tested and considered promising. Lactic fermentation of composite flour/water mixtures containing 10, or 20% powdered roasted mealworm larvae resulted in successful acidification and was demonstrated effective in safeguarding shelf-life and safety by the control of Enterobacteria and bacterial spores.