This work studies the effect of rendering on quality of meat and bone meals (MBM) processed in two Spanish rendering plants according to the standard procedure recommended by 96/499/EC Directive for MBM category III. Twelve samples of raw animal by-products and their corresponding meals were analyzed for chemical composition, amino acids content, FDNB-reactive lysine content, pepsin digestibility, protein dispersibility index and fatty acids content.
The results indicate rendering has negative effects on protein and fat quality of MBM. Variability between and within plants is attributed to differences in raw material, processing conditions and fat removing efficiency. Continuous monitoring is recommended to ensure the quality of each batch before use.