Macronutrients- Protein Function Food sources Requirement composition body tissues Milk production, >Breast egg, fish, meat, feeding Important role in body 2g/kg/d bean etc cow milk growth and maintenance The quality of feeding animal protein is 3.5g/kg/d better than plant Plant protein protein feeding 4g/kg/d ine essential amino acids: histidine, isoleucine, leucine, lysine methionine, phenylalanine, threonine, tryptophan, and valine Conditional essential amino acids: cystine, taurine, arginineFunction ➢ composition body tissues. ➢ Important role in body growth and maintenance Food sources Requirement ➢ Milk production, egg, fish, meat, bean etc. ➢ The quality of animal protein is better than plant protein ➢ Breast feeding 2g/kg/d ➢ cow milk feeding 3.5g/kg/d ➢ Plant protein feeding 4g/kg/d Macronutrients - Protein Nine essential amino acids: histidine，isoleucine, leucine, lysine methionine, phenylalanine, threonine, tryptophan, and valine Conditional essential amino acids: cystine, taurine, arginine