Peanuts. A 1-ounce (28-gram) serving of Spanish peanuts contains 0.5 grams of leucine ( 41 ).

What foods is leucine in?

Dairy, soy, beans, and legumes are sources of leucine. Phenylalanine is in dairy, meat, poultry, soy, fish, beans, and nuts.

Do peanuts have all essential amino acids?

After the peanut oil is extracted, the protein content in the cake can reach 50 % (Zhao et al. 2011). Peanuts contain all the 20 amino acids in variable proportions and is the biggest source of the protein called “arginine” (USDA 2014).