In Vitro Crude Protein Digestibility of Tenebrio Molitor and Hermetia Illucens Insect Meals and its Correlation with Chemical Composition Traits

Abstract

The aims of this study were to evaluate the correlation between in vitro crude protein digestibility coefficients of insect meals from Tenebrio molitor (TI) and Hermetia illucens (HI) and their chemical composition traits as well as to develop regression equations able to estimate the in vitro crude protein digestibility (CPd) from proximate analysis of insect meals. Twelve samples of insect meals (6 from TM larvae, TM 1-6 and 6 from HI larvae, HI 1-6) were obtained from different producers and analysed for chemical composition and in vitro crude protein digestibility by a two-step enzymatic method (digestion with pepsin and trypsin-enriched pancreatin). For both insect meal samples, CPd was negatively correlated to ADF and chitin contents, while just for HI there was a positive correlation (P<0.01) between CP percentage of the samples and CPd. For both insect meals the former variable chosen in the stepwise analysis was the chitin, explaining the 79.45% of CPd variability for Tenebrio molitor samples and the 98.30% for Hermetia illucens. In the second step, the amount of protein linked to ADF was added in the model for T. molitor and CP for H. illucens samples. The coefficients chitin is the main constituent of insect body able to affect the crude protein digestibility of Tenebrio molitor and Hermetia illucens larvae meals estimated by an in vitro enzymatic method.

Identification of antioxidant and anti‐inflammatory peptides obtained by simulated gastrointestinal digestion of three edible insects species (Gryllodes sigillatus, Tenebrio molitor, Schistocerca gragaria)

“…Chitin is not degraded and absorbed in the small intestine (Vidanarachchi et al, 2010) and thus can affect protein digestibility (Bovera et al, 2015). This is in agreement with Marono et al (2015), who indicated chitin as the main factor affecting the in vitro protein digestibility of insect meals. However, further investigations need to clarify this point.…”

“…This is in agreement with Marono et al . (), who indicated chitin as the main factor affecting the in vitro protein digestibility of insect meals. However, further investigations need to clarify this point.…”

Black soldier fly (Hermetia illucens) pre-pupae meal as a fish meal replacement in diets for European seabass (Dicentrarchus labrax)

“…This seems to indicate that insect meals are well digested by seabass. These in vivo ADC data are considerably higher than the in vitro crude protein digestibility determined for H. illucens and T. molitor determined by Marono et al (2015), which ranged from 65.8 to 68.7%. This indicates that the in vitro method may not be adequate for estimating the ADC of protein for fish (Gomes et al 1998;Moyano et al, 2015).…”

Standardized ileal digestible amino acids and apparent metabolizable energy content in defatted black soldier fly larvae meal fed to broiler chickens

“…For BSFLM samples, the amount of protein linked to ADF was determined and used to estimate the amount of chitin. According to Marono et al (2015), chitin (%) = ash free ADF (%) − ADF-linked protein (%). The ADF-linked protein was derived from the concentration of N in ADF residue.…”