Effects of threonine supplementation on the slope assay for protein quality
McLaughlan, J.M.; Keith, M.O.
Journal - Association of Official Analytical Chemists 60(6): 1291-1295
1977
ISSN/ISBN: 0004-5756 PMID: 924931 Document Number: 121989
Young rats were given diets containing soya or pea protein each with added methionine, rice and casein, or groundnut, sesame and fish. The diets had 3 to 9% protein and were marginally deficient in threonine. Chemical and plasma amino acid scores indicated that threonine was limiting at 3 to 4% protein. With threonine supplements growth increased, all proteins except pea were limiting in lysine, and relative protein value (RPV) but not protein efficiency ratio decreased. It was concluded that the RPV test underestimates the protein quality of lysine-deficient proteins.