Determinant production factors to the in vitro organic matter digestibility and protein oxidation of poultry by-product meal

The quality of poultry by-product meal (PBM) is not standardized in the industry. Several fac-tors are detrimental to PBM and compromise its nutri-tional value and shelf life. Therefore, this study was conducted to determine the main PBM production fac-tors that directly affect its in vitro organic matter digest-ibility (IVDOM) and protein oxidation (POX). Data on the processing of PBM samples (n = 100) were recorded in a rendering plant. Two types of PBM were used: 1) Low ash (LA, n = 66) with mineral matter (MM) content of 11% and 2) High ash (HA, n = 34) with MM above 11%. Processing traits and chemical composition of PBM were considered independent varia-bles. The IVDOM and POX were determined in each sample and considered dependent variables. Data on independent variables were submitted to factorial and principal components (PC) analyses. In vitro organic matter digestibility data were clustered (P = 0.001) in low (778.92 g/kg), average (822.85 g/kg), and high (890.06 g/kg). The best arrangement was composed of six independent variables distributed in two PC, which explained 82.10% of the total variation. The ash concen-tration, oil to raw material ratio, collagen, and crude protein comprised PC1 with greater relevance and explained 58.46% of the total variance. The PC2 was composed of the processing time and temperature and explained 23.64% of the total variance. Protein oxida-tion data were clustered (P < 0.001) in low (265.19 nmol/mg CP), average (393.07 nmol/mg CP), and high (524.40 nmol/mg CP). Based on our results, the composition of the raw material from the slaughter-house holds most of the information on PBM composi-tion and digestibility. Developing improvements in the slaughtering or in the screening of the raw material that will be used by the rendering process is important to obtain a more nutritionally standardized ingredient.

Automated summary

The quality of poultry by-product meal (PBM) is not standardized in the industry. Factors such as ash concentration, oil to raw material ratio, collagen, crude protein, processing time, and temperature directly affect the organic matter digestibility and protein oxidation of PBM. The composition of the raw material from the slaughterhouse holds most of the information on PBM composition and digestibility.