Black soldier fly larvae (BSFL) are increasingly seen as ideal candidates to turn organic streams into biomass that could be upcycled in the food system as either animal feed or human food. While many studies have focused on finding nutrient conversion efficiencies of BSFL fed on a wide variety of organic streams, limited attention has been given to the gaseous emissions produced during the rearing. The quantification of these gaseous emissions is crucial to understand emission patterns, develop mitigation strategies, and clarify the potential environmental benefits of utilizing them as feed or food. Here, we reared 7-days old BSFL larvae in respiration chambers to continuously measure the production of gases of environmental concern (i.e., CO2, CH4, N2O and NH3). Two different substrates were tested: a mass rearing diet made from by-products of plant origin, and pig manure. With the mass rearing diet, nearly no CH4 was detected. CO2 and N2O emissions quickly increased up to the 5th day of measurements and then dropped. By contrast, NH3 was only produced after the peak in CO2 levels occurred. We found evidence that more than 30% of the CO2 produced was produced by the microbial biomass of the substrate. When BSFL was reared in pig manure, methane was produced during the first 3 days of measurements and then steadily dropped. CO2 and NH3 were produced all along, but reached their maximum during the 6th and 7th day. N2O steadily increased over time. In addition, we found that when BSFL were reared in pig manure, NH3 emissions were twice higher than those found for pig manure without BSFL. Our results are relevant for the improvement of BSFL conversion efficiencies and for the reduction of gaseous emissions during BSFL rearing.

Enhancing or adjusting to environmental conditions, such as temperature and relative humidity, in a BSF farm can optimize the rearing efficiency of the process. Adjustments of these parameters in the colony can lead to an increased rearing success which is interesting for already established farms or help to guide the type of setup for those planning to establish new farms.

Currently all production systems in the world seem to go for trays, with the related investment and inefficiency related to that. There is an proven alternative. Vertical racks for automated filling, feeding and emptying. A system where you work in climate controlled rooms but have no moving parts in the room. Suitable for each country in the world because you can work with workers and don't need high skilled engineers.

The research conducted in the last 20 years has shown that BSF larvae are a reliable source of protein and lipid in feeds for farmed animals, especially for aquaculture. Breeding these flies under optimal and stable abiotic parameters often requires indoor facilities. Those are highly costly, require a large amount of empty space, and most of the time their egg production does not match that of outdoor cages. However, in places with plenty of sunlight and stable abiotic parameters, optimal outdoor cage designs can bring the costs of mass production to significantly lower levels than indoor facilities. Here, we present some details of the past and current outdoor insectarium designs developed by Nutrition Technologies that can optimize the mass production of this insect to meet demands, at a low cost and reduced environmental footprint. An Overview of the cage designs and key lessons learned will be shared.