Proximate and fatty acid profile analysis of Tenebrio molitor and Zophobas morio using different killing methods

The present work aimed to quantify the macronutrients and the fatty acid (FA) profile in different killing methods, blanching (BC) and freezing (FR), on edible insects of the speciesTenebrio molitor(TM) andZophobas morio(ZM). Concerning macronutrients TM-BC and TM-FR presented 51.2% and 50.6% of protein, 28% and 29.4% of lipids, and 12.4% and 11.4%. Meanwhile, ZM-BC and ZM-FR expressed 42.8% and 43.7% of protein, 39.1% and 40.1% of lipids, and 10.7% and 8.9% of carbohydrates. The FA of TM and ZM shows respectively values of Saturated Fatty Acids (∑SFA) 30% - 45%, Monounsaturated (MUFA) 47% - 32%, Polyunsaturated (∑PUFA) 23% - 22%, Atherogenicity Index (AI) 0.64 - 0.75, Thrombogenicity Index (TI) 0.77 - 1.44 and hypocholesterolemic/hypercholesterolemic index (h/H) of 2.50-1.51. Based on the results obtained, the slaughter methods showed statistically differences in relation to MUFA's in TM, and ZM larvae only in the minority fraction of FA.

Biodegradation of Polystyrene by Plastic-Eating Tenebrionidae Larvae

Polystyrene (PS) is an extremely stable polymer with a relatively high molecular weight and a strong hydrophobic character that makes it highly resistant to biodegradation. In this study, PS was subjected to biodegradation tests by Tenebrio Molitor (T. Molitor) and Zophobas Morio (Z. Morio) larvae. Specifically, six different experimental diets were compared: (i) T. Molitor fed with bran; (ii) T. Molitor fed only PS; (iii) T. Molitor fed only PS treated with H2O2; (iv) Z. Morio fed with bran; (v) Z. Morio fed only PS; and (vi) Z. Morio fed only PS treated with H2O2. Therefore, the mass change of the larvae and the survival rate were measured periodically, while the frass collected after 15 and 30 days was analyzed by different analyses, such as spectroscopy (FTIR), spectrometry (molecular weight and polydispersity), thermal analysis (TGA) and microscopy (scanning electron microscopy observations). The obtained results suggest that in the case of T. Molitor larvae, larvae feeding on bran showed the highest survival rate of ~94% at 30 days, while in the case of the Z. Morio larvae, the highest survival rate was exhibited by larvae eating PS-H2O2. Although not strongly pronounced, the Mw and Mn of PS in the frass of both T. Molitor and Z. Morio larvae decreased over 30 days, suggesting PS biodegradation. Finally, the morphological analysis shows that PS samples isolated from the frass of T. Molitor and Z. Morio larvae showed completely different, rough and irregularly carved surface structures, in comparison to PS before biodegradation.

Classification of Zophobas morio and Tenebrio molitor using transfer learning

Zophobas Morio and Tenebrio Molitor are popular larvae as feed ingredients that are widely used by animal lovers to feed reptiles, songbirds, and other poultry. These two larvae share a similar appearance, however; the nutritional ingredients are significantly different. Zophobas Morio is more nutritious and has a higher economic value compared to Tenebrio Molitor. Due to limited knowledge, many animal lovers find it difficult to distinguish between the two. This study aims to build a machine learning model that is able to distinguish between the two. The model is trained using images that are taken from a standard camera on a mobile phone. The training is carried on using a deep learning algorithm, by adopting an architecture through transfer learning, namely VGG-19 and Inception v3. The experimental results on the datasets show that the accuracy rates of the model are 94.219% and 96.875%, respectively. The results are quite promising for practical use and can be improved for future works.

Effects of mealworm (Tenebrio molitor) larvae hydrolysate on nutrient ileal digestibility in growing pigs compared to those of defatted mealworm larvae meal, fermented poultry by-product, and hydrolyzed fish soluble

OBJECTIVE

To investigate effect of mealworm (Tenebrio molitor) larvae hydrolysate on nutrient ileal digestibility compared to those of dried mealworm larvae meal, fermented poultry by-product, and hydrolyzed fish soluble in growing pigs.

METHODS

A total of 12 crossbred ([Landrace×Yorkshire]×Duroc) growing pigs with average body weight of 28.70±0.32 kg were surgically equipped with simple T-cannulas. A total of 12 pigs were assigned to individual metabolic crates and allotted to one of four treatments with 3 replicates in a fully randomized design.

RESULTS

Apparent ileal digestibility (AID) of dry matter (DM) was the highest in pigs fed HML diet. AIDs of crude protein (CP) were higher in pigs fed HML and DMLM diets than those in pigs fed the other two diets. AID of total amino acid was higher (p = 0.06) in pigs fed HML diet. AIDs of lysine (Lys), methionine (Met), and threonine (Thr) were similar in pigs fed DMLM and HML diets, but were higher (p = 0.05, p<0.05, and p = 0.05, respectively) than those in pigs fed FPBM or HFS diet. Pigs fed HML diet had higher standardized ileal digestibilities (SIDs) of DM and CP (p<0.05 and p<0.05, respectively) compared to pigs fed the other FPBM and HFS diets. SIDs of total amino acid were not different (p = 0.06) between treatments. For SIDs of Lys, Met, and Thr, pigs fed HML and DMLM diets showed higher SIDs (p = 0.05, p<0.05, and p<0.05, respectively) than pigs fed FPBM and HFS diets. SIDs of non-essential amino acids (aspartic acid, glycine, and alanine) were higher (p<0.05, p< 0.05, and p<0.05, respectively) in pigs fed HML, FPBM, and DMLM diets than those in pigs fed the HFS diet. AID and SID of glutamic acid were higher in pigs fed HML and FPBM diets.

CONCLUSION

In conclusion, dietary supplementation of mealworm larvae hydrolysate had higher digestibility in DM, CP, Lys, Met, and Thr compared to dietary supplementation with fermented poultry by-product and hydrolyzed fish soluble.