Near Infrared Spectroscopy as a Traceability Tool to Monitor Black Soldier Fly Larvae (_Hermetia illucens_) Intended as Animal Feed  
[PERSON]  
1 Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation (QAAFI), The University of Queensland, Brisbane, QLD 4072, Australia 12  
[PERSON]  
1 Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation (QAAFI), The University of Queensland, Brisbane, QLD 4072, Australia 12  
[PERSON]  
1 Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation (QAAFI), The University of Queensland, Brisbane, QLD 4072, Australia 1  
[PERSON]  
1 Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation (QAAFI), The University of Queensland, Brisbane, QLD 4072, Australia 14  
[PERSON]  
2 Centre for Animal Science, Queensland Alliance for Agriculture and Food Innovation (QAAFI), The University of Queensland, Brisbane, QLD 4072, Australia 1  
[PERSON]  
6 Gotterra, 14 Arnot Street, Hume, ACT 2620, Australia 6  
[PERSON]  
1 Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation (QAAFI), The University of Queensland, Brisbane, QLD 4072, Australia 1  
process of plant biomass by animals [2]. Feedstock is observed to be responsible for around 65-85% of livestock production costs. The water footprint, land footprint, and mineral footprint of livestock production using conventional feed ingredients such as grain and cereals have suggested the need for viable and sustainable feed sources [3]. Annually, 1.3 billion tonnes of food produced for human consumption is wasted, and the management of these waste streams through landfills and incineration is observed to have a negative impact on the environment [4]. The valorisation of this food waste using black soldier fly larvae (BSFL) and their subsequent use as feedstock has received much attention lately [5; 6; 7; 8]. Black soldier flies (_Hermetia illucens_ L. 1758; Diptera: Striationyidae) are widely distributed in tropical and subtropical regions [9]. The life cycle of BSFL begins with the adult female fly's oviposition, laying around 200-600 eggs [10; 11]. The eggs are laid on dry surfaces, and the hatching of eggs into larvae usually takes place within 4 days [12]. BSFL go through six larval instars, and these larvae are polyphagous saprophagous and can actively forage on a variety of organic products [13]. The duration of this larval stage can range between 10 and 52 days depending upon the type of substrate, temperature, and humidity of the feeding environment [10]. Larval instars 1-4 are whitish in colour, creamy in appearance, and differ in length and size. The length of the first, second, third, and fourth instar larvae vary between 2-5 mm, 6-9 mm, 10-13 mm, and 14-16 mm, respectively. The fifth instar larvae are brownish-grey in colour and are about 17-20 mm in length. The pre-pupae (sixth instars) are characterised by a prominent dark brownish-black colour and are around 20-22 mm in length [14; 15; 16]. It is noteworthy that the morphological features of different larval instars are influenced by the substrate and rearing conditions [10]. BSFL, upon reaching the pre-pupal stages, stop feeding and move away from the feed [17]. The emergence of pupa from sixth-instar BSFL or the pre-pupa takes 14 days and involves six stages of moulting [11]. The pupae develop into adult BSF normally in 10-14 days under suitable environmental conditions. The adult BSF are 15-20 mm in length [18]. The adult flies do not have mouthparts, and they rely on their fat stores and liquid supplements for survival and mating [17]. The mating between the male and female adult flies commences two days after eclosion during flight or in the ground under sunlight or similar environmental conditions, and successful mating leads to ovipesting in two days [19; 20].