Effect of processing with sodium hydroxide, calcium oxide, hydrobromic acid, and hydrogen peroxide on nutritional value of lentil (Lens culinaris) residues

This research was conducted to investigate the effect of processing with sodium hydroxide (NaOH, 50 g/kg DM), calcium oxide (CaO, 160 g/kg DM), hydrobromic acid (HBr, 60 ml/kg DM), and hydrogen peroxide (H2O2, 57 ml/kg DM) on the nutritional value of lentil (Lens culinaris) residues. Gas production test was used to estimate the parameters of gas production in samples. In vitro digestibility of the samples was determined by the batch culture method. Processing was effective on the residue's chemical composition (P<0.05). CaO, H2O2, and NaOH treatments increased the Ash compared to the control. Crude protein (CP) decreased in the processed samples, which was the lowest in the H2O2 and CaO treatments. Treatments of H2O2 and NaOH decreased the neutral detergent fiber (NDF) and acid detergent fiber (ADF) and increased total digestible nutrients (TDN), net energy for lactation (Nel), and net energy for growth (Neg). Gas production potential and related estimated parameters were less in treated samples than in the control group (P<0.0001). Dry matter digestibility (DMD) in NaOH and CaO treatments and organic matter digestibility (OMD) in HBr and CaO treatments decreased compared to the control (P<0.0001). All treatments increased the amount of partitioning factor (PF) compared to the control (P<0.0001). The highest amount was observed in H2O2 and HBr treatments (P<0.0001). H2O2 increased the microbial biomass (MB) and its efficiency (P<0.0001). Overall, although processing improved the chemical composition of lentil residues, it did not have a positive effect on gas production parameters and in vitro digestibility of the samples.