Food safety concerns in edible grasshoppers: a review of microbiological and heavy metal hazards

Abstract

The use of insects as food and feed is widespread worldwide due to their attractive nutritional profile comparable to that of conventional livestock. In particular, edible grasshoppers act as a food source to many tribes in East and Central Africa but still harvested from their natural habitats. In this perspective, the health hazards associated with consumption of grasshoppers ought to be investigated. The present review assesses the risks (microbiological and heavy metals hazards) of wild-harvested Ruspolia differens (Serville) (Orthoptera: Tettigonidae) and compares with the levels recommended for minced meat as an indicator of food safety for edible insects. In addition, the effect of common processing methods in reducing the risks is stated. Due to the scarcity of the data, other edible grasshoppers within the order Orthoptera have been included in the review. The risks identified as main hazards include: (1) high total viable counts; (2) high counts of Enterobacteriaceae and lactic acid bacteria; (3) high counts of yeasts and moulds; and (4) accumulation of lead and other heavy metals. Conventional processing methods are effective in reducing microbiological hazards except for bacterial endospores. Important data gaps regarding edible grasshoppers and their safety include: (1) lack of data on bacterial communities (raw and processed); (2) fungal communities and mycotoxins-producing fungi; (3) studies on shelf life of processed edible grasshoppers; (4) limited data on heavy metals on whole grasshoppers and derived products; and (5) lack of data on parasites, viruses, antimicrobial resistance and veterinary medicinal products. Future aspect should focus on sustainable farming of grasshoppers using different diets in controlled environments and risks profiling. The present review explores food safety risks related to consumption of edible grasshoppers, from wild collections to consumption.