Influence of thermoplastic extrusion on the nutritive value of bovine rumen protein

• Grant number: 09/17050-5
• Support Opportunities: Regular Research Grants - Publications - Scientific article
• Start date: December 01, 2009
• End date: November 30, 2010
• Field of knowledge: Agronomical Sciences - Food Science and Technology - Food Science
• Principal Investigator: José Alfredo Gomes Arêas
• Grantee: José Alfredo Gomes Arêas
• Host Institution: Faculdade de Saúde Pública (FSP). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

This study investigated the impact of thermoplastic extrusion on the nutritive quality of bovine rumen protein. Proximal composition, amino acid profile and in vivo true protein digestibility among rats were determined in raw (RBR) and extruded (EBR) rumen. Raw and extruded bovine rumen presented high percentages of protein (more than 95% on dry basis). Neither raw nor extruded proteins had any limitingamino acid, and the RBR and EBR amino acid scores were, respectively, 1.28 (leucine) and 1.25 (methionine plus cystine). Extrusion reduced significantly true protein digestibility from 97.7% to 93.1% (p < 0.001), but protein digestibility-corrected amino acid scores for both proteins (RBR and EBR) were 100%. Animal growth presented comparable profiles using raw and extruded rumen. In conclusion, thermoplastic extrusion did not affect the protein quality of bovine rumen, and this does not hinder the use ofthis material as a food ingredient. (AU)