Poster Topical Area: Energy and Macronutrient Metabolism
Location: Hall D
Poster Board Number: 525
Objectives: To assess the protein quality of Indian wheat by studying the metabolic availability (MA) of the most limiting amino acid; lysine, and to assess the effect of protein complementation by providing a mixed meal of wheat and lentils.
Methods: MA was studied with a repeated measures design using the indicator amino acid oxidation (IAAO) method in 5 young men with L-[1-13C] phenylalanine as the indicator amino acid at four levels of Lysine: 5, 8, 12 and 15 mg.kg-1.d-1 (i.e, 13.6, 21.7, 32.5 and 40.7 % of the mean lysine requirement of 36.9 mg.kg-1.d-1, respectively). Each subject participated in 8 experiments: 4 lysine intakes as L-lysine from crystalline amino acid, 3 intakes of lysine from wheat prepared as a bread and 1 experiment for dietary complementation with lentils. Based on the principles of the slope-ratio assay, the MA of lysine was calculated by comparing the IAAO response to varying intakes of protein-bound lysine in baked wheat bread compared with the IAAO response to free crystalline L-Lysine in the reference protein (patterned after egg protein).
Results: Preliminary data from 4/5 subjects show a MA of lysine from baked Indian wheat bread of 90%.
Conclusions: Despite being of limiting concentration in wheat, most of the lysine present is available for protein synthesis when wheat is baked to golden color bread.
Supported by The Canadian Institute of Health Research (FRN 148864).
Graduate Restracomp Scholarships by The Hospital for Sick Children Research Institute
University of Toronto
Vaughan, Ontario, Canada