The nutritive value of the residues remaining after oil extraction from seeds of evening primrose (Oenothera biennis L)

The composition and nutritive value of residues of seeds of evening primrose (Oenothera biennis) after oil extraction were determined. Seeds contained 17% fat and 22·2% protein. This protein was rich in sulphur amino acids but poor in lysine (4·9 and 1·8 g per 16 g of N) respectively. Seeds had also high antitrypsic activity (35800 IU). The true digestibility of protein was low (32) but its biological value was high (81). Boiling in water improved the protein digestibility but lowered its biological value (77).