Ice nucleation is a stochastic process and it is very difficult to be controlled. Freezing technologies and more specifically crystallisation assisted by magnetic, electric and electromagnetic fields have the capability to interact with nucleation. Static magnetic field (SMF) may affect matter crystallisation; however, this is still under debate in the literature. Static electric field (SEF) has a significant effect on crystallisation; this has been evidenced experimentally and confirmed by the theory. Oscillating magnetic field induces an oscillating electric field and is also expected to interact with water crystallisation. Oscillating electromagnetic fields interact with water, perturb and even disrupt hydrogen bonds, which in turn are thought to increase the degree of supercooling and to generate numerous fine ice crystals. Based on the literature, it seems that the frequency has an influence on the above-mentioned phenomena. This review article summarizes the fundamentals of freezing under magnetic, electric and electromagnetic fields, as well as their applicability and potentials within the food industry.

Entomophagy has been part of human diets for a long time in a significant part of the world, but insects are considered to be a novel food everywhere else. It would appear to be a strategic alternative in the future of human diet to face the challenge of ensuring food security for a growing world population, using more environmentally sustainable production systems than those required for the rearing of other animals. Tenebrio molitor, called yellow mealworm, is one of the most interesting insect species in view of mass rearing, and can be processed into a powder that ensures a long shelf life for its use in many potential products. When considering insects as food or feed, it is necessary to guarantee their safety. Therefore, manufacturers must implement a Hazard Analysis Critical Control plan (HACCP), to limit risks for consumers’ health. The aim of this case study was to develop a HACCP plan for Tenebrio molitor larvae powders for food in a risk-based approach to support their implementation in industry. Specific purposes were to identify related significant biological hazards and to assess the efficiency of different manufacturing process steps when used as Critical Control Points. Then, combinations of four different processes with four potential uses of powders by consumers in burger, protein shake, baby porridge, and biscuits were analyzed with regard to their safety.

Tenebrio molitor, the first edible insect approved as a novel food in the EU, is a promising candidate for alternative protein sources, implementing circular and sustainable production systems. This study aims to determine the microbiological quality and physicochemical properties of mealworm powders obtained by four different processing pathways. Contents of dry matter, protein, fat, ash, water activity (aw) and a range of microbial counts were measured and analyzed by one-way ANOVA with Tukey’s test. Results showed small differences in the proximate composition of the powder samples (protein 55.62–57.90% and fat 23.63–28.21% of dry matter, DM), except for the one that underwent a defatting step (protein 70.04% and fat 16.84%), p < 0.05. A level of water activity of less than 0.2 was reached for all pathways. Fresh mealworm samples had high total aerobic counts (8.4 log CFU/g) but were free of foodborne pathogens. Heat treatments applied during transformation were sufficient to kill vegetative cells (reduction of 2.8–5.1 log CFU/g) rather than bacterial endospores (reduction of 0.3–1.8 log CFU/g). Results were confirmed by predictive microbiology. This study validated the efficacy of a boiling step as critical control points (CCPs) of insect powder processing, providing primary data for the implementation of HACCP plans.

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.