PKU trio 400g (14.11 ounce) Powder, Unflavored. 1,620 Calories per Can. PKU trio is a powdered phenylalanine free medical food containing a blend of essential and non-essential amino acids, carbohydrate, fat, vitamins, minerals and trace elements. Available in unflavored and vanilla flavored options. For use in the dietary management of Phenylketonuria (PKU). Suitable for individuals from 1 year of age through to adulthood.