Processing edible insects into powders: a review of available processes and potential microbial inactivation methods

Abstract

In Europe, people are increasingly interested in edible insects to meet the growing demand for food diversity and protein supply, and bring expected nutritional and environmental benefits. Among all insect-based foods, insect powder is one of the most promising choices, which presents added advantages in the ability of mixing with versatile ingredients, long shelf-life and higher consumer acceptance (non-recognisable form). As a novel protein source, insects require the well-designed manufacturing process to produce high quality insect powder, while guaranteeing food safety of the final product. This review provides a brief overview of the current consumption patterns and general processing steps of insect powders. With regard to inactivating potential microbial hazards, traditional thermal treatment (e.g. boiling, blanching,) is still the predominant method in insect sector, which shows a desirable microbial reduction but may affects nutritional properties and organoleptic attributes. The use of food preservatives and fermentation have also been incorporated as means for eliminating pathogenic bacteria in some insect products. Recent years, a set of advanced or innovative technologies have been developed for inactivation of microorganisms in various foods while maintaining food quality, such as infrared heating, instant control pressure drop technology, high hydrostatic pressure, and cold plasma. However, except for the initial exploration of very few techniques in the laboratory, most novel technologies have not been attached much importance in insect sector. Eventually, this review highlights the lack of data on the impacts of different processing methods (both conventional and innovative, individual or in combination) for edible insects, encompassing the control of microbial activities, nutritional value, and sensory qualities.