Expanded polystyrene and whey goat as substrates for Tenebrio molitor breeding

The objective of this work was to evaluate expanded polystyrene [EPS] and goat whey as substrates for rearing Tenebrio molitor larvae, analyzing microplastic residues in their flour and feces, and assessing nutritional impacts. Larvaes were raised in darkness at 20 ± 1 °C for 28 days across four treatments [substrates]: wheat bran/carrot [control], EPS, EPS with whey, and bran/carrot with whey. Flours obtained were analysed: protein, fat, and ash content using Lowry, Soxhlet, and gravimetric methods, respectively. FTIR spectrometry were used to determined microplastics residues in feces and in flour. Results showed microplastics in feces, indicating incomplete EPS degradation by the larvae. The bran/carrot/whey treatment yielded the highest larval weight [77.5 ±4.94 g] and a flour yield of 32-33%w/w, while EPS groups had the lower fat content 2.65 5.24%w/w and higher ash content 8.55-10.07%w/w.