Chitin, and especially its deacetylated variant chitosan, has many applications, e.g. as carrier material for pharmaceutical drugs or as a flocculant in wastewater treatment. Despite its versatility and accessibility, chitin, the second most abundant polysaccharide on Earth, has so far been commercially extracted only from crustaceans and to a minor extent from fungi. Insects are a viable alternative source of chitin, but they have not been exploited in the past due to limited availability. Today however, for the sustainable production of animal feed, insect farming is being developed substantially. The availability of large quantities of insect biomass and chitin-rich side products such as exuviae and exoskeletons has been increasing. This review provides an overview of recently published studies of chitin extraction from insects, its subsequent conversion into chitosan and the primary analytical methods used to characterize insect-based chitin and chitosan. We have discovered a large number of research articles published over the past 20 years, confirming the increased attention being received by chitin and chitosan production from insects. Despite numerous publications, we identified several knowledge gaps, such as a lack of data concerning chitin purification degree and chitosan yield. Furthermore, analytical methods used to obtain physicochemical characteristics, structural information and chemical composition meet basic qualitative requirements but do not satisfy the need for a more quantitative evaluation. Despite the current shortcomings that need to be overcome, this review presents encouraging data on the use of insects as an alternative source of chitin and chitosan in the future.

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The production of food is an intensive source of environmental impact. In aquaculture, one source of impact is solid waste, which contains high concentrations of minerals, other nutrients, and metals. The larvae of Hermetia illucens are capable of consuming this material, but applying technology that is based on these larvae for managing waste streams, like those from aquaculture, requires careful examination of safety risks. A study is performed examining the growth performance of larvae that were fed on solid aquaculture waste. Subsequently, a thorough analysis of safety risks from inorganics, with detailed the results on microelements that have previously received little attention in the literature, is performed to serve as a guideline for how to assess the safety of waste streams such as these. Findings confirm existing results in the literature that Cd is bioaccumulative, but also that other elements, including Hg, Mn, and especially K, are bioaccumulative. To the authors’ knowledge, this is the first research where the accumulation of Ag is also tested. The results of these tests are explained within the context of regulations in various countries where Hermetia illucens is cultivated, serving as a reference for practitioners to rigorously screen out high risk feed streams that they may consider using as feed sources. It is intended that these references and the demonstrated accumulation of a range of elements motivate comprehensive industry safety practices when evaluating new feed sources.

Feather pecking is a key welfare challenge in laying hen husbandry. Feeding of live Hermetia illucens larvae could provide a possible solution to reduce feather pecking in hens. This research investigates effects of dispensing live H. illucens larvae to non-beak trimmed older laying hens on production performance, behavior and welfare. Control treatment hens were provided a commercial diet, while larvae treatment hens were provided live H. illucens larvae (using special dispenser) on top of a soy-free diet. Feather condition, production performance and egg quality were measured during the initiation (67 weeks age) and termination (78 weeks age) of the trial. Behavior of birds was monitored using video recording. Feed conversion ratio, body weight gain and egg laying parameters were similar for both treatments. At termination of the trial, larvae-fed hens exhibited better feather condition in comparison to control hens (p = 0.004). Behavioral observations indicated that larvae provision influenced the number of birds on floor during morning and afternoon hours. In conclusion, live H. illucens larvae could successfully replace soy in diets of older laying hens (in combination with local plant proteins). Provisioning of these insects also had a positive effect on the feather condition of laying hens with intact beaks.