Systematic review of protein quality and n-6 and n-3 lipid profile of alternative ingredients for ready-to-use therapeutic foods (RUTF)

Background: Ready-to-Use Therapeutic Food (RUTF) is a lipid-based food used for the treatment of children with severe wasting. Due to its current high cost, formulations using alternative ingredients have been proposed. However, guidance on alternative ingredients for RUTF, especially to meet Codex regulations, is missing in the literature. Hence, this paper aims to provide a guide on the nutritional value of alternative RUTF ingredients, focusing on protein quality and n-6/n-3 fatty acid ratio. Scope and approach this study used three approaches: First, we systematically reviewed the literature and public tenders from the United Nations Children's Fund on new RUTF formulations. Then, a compilation of alternative ingredients used in these formulations were made and analysed. Second, we estimated the protein quality – using the protein digestibility-corrected amino acid score (PDCAAS) – and n-6 and n-3 fatty acid profiles of the alternative ingredients using national databases and data from the literature. The content of typical antinutritional factors in these ingredients were also reported. Third, we estimated the PDCAAS, protein content from dairy sources, added sugar content, and n-6/n-3 fatty acid ratio of sample RUTF formulations using alternative ingredients. Key findings and conclusions: Using alternative ingredients in RUTF have varying effects on the PDCAAS and fatty acid profile of the final RUTF product. The data presented in this paper will help guide manufacturers and developers of modified RUTF formulations on the use of alternative ingredients and their effect on the nutritional properties of the resulting RUTF product to comply with the 2022 Codex guidelines.