Characteristics of North American Meat and Bone Meal Relevant to the Development of Non - Feed Applications

Unmarketable animal tissues are typically processed by rendering plants, which transform them into meat and bone meal (MBM) or similar products. MBM’s traditional use as animal feed has become increasingly threatened, but MBM has potential for non-feed applications. Development of new products and processes is hindered by lack of reliable data on many of MBM’s chemical and physical properties. MBM samples, as well as data on raw material and process, were collected from 19 rendering facilities in the United States and Canada. A large majority of the raw material was tissue from cattle, swine, and poultry. All facilities surveyed practiced continuous dry rendering; 89% of the facilities use continuous cookers and 11% use falling film evaporators. MBM is high in protein (44.6-62.8%, mfb), but this protein is poorly soluble; at pH 7 solubility ranged from 2.20% to 7.22%. Among all samples, the particles’ median geometric mean diameter was 387 m, and the size distribution was broad. The median density of MBM particles was 1.41 (g/mL); median density of MBM in bulk ranged from 0.50 g/mL when loose-filled to 0.68 g/mL when packed. pH values of the samples ranged from 5.89 to 7.19, and samples containing the most cattle tissue had the highest pH. Thermal diffusivity and thermal conductivity values for both loose-filled and packed MBM are reported, as well as CIE L*a*b* color values.