Abstract: Throughthe hydrolysis catalyzedby papainthe leaf protein’ s functional defects were overcome.The p -roduct’ s nutritional value was estimated th rough the measurement of the amino ac id’ s amount andthe rat’ s growth and metabolism experiment.The result s howed:while the hydrolysis produce d peptides,a lot free amino acid was r e-leased.The amount of essential amin o acid,namely,Lys,Thr,Leu,Ile and Trp increased greatly.The result of rat’ s growth and metabolismexperiment re vealed:the nutritive value indexes of leaf proteinpeptides showedmark ed differ-ence against leaf protein;while clo se to casein.

Key words: Leaf proteinpeptide , Free amino acid , Nutritional value