In vitro methods to assess the nutritive value of leaf protein concentrate

Leaf protein concentrate (LPC) from 9 plants was analysed for in vitro digestibility and amino acid composition by chemical methods. These LPC were also assessed in animal experiments for true digestibility and net protein ratio (NPR). There were marked differences among the LPCs in amino acid composition (available lysine, S amino acids, histidine, and tryptophan), pepsin and pepsin-pancreatin digestibility, and the food intake, growth, and digestibility in the animal experiments. There were good correlations between in vitro and in vivo digestibility, between S amino acids and NPR, and among the changes in various amino acids and available lysine. Pepsin-pancreatin digestibility, available lysine, and contents of S amino acids promise to be a sensitive and rapid in vitro measure of the nutritive value of LPC.