Long story short: no, beans are not considered one of the independent sources of complete protein, but they can easily become complete when paired with whole grain rice or cornbread (which go together as well as red beans and rice in that they’re all complete proteins ).
While beans have one of the highest protein contents within plant based food items, beans do not have all the essential amino acids needed in an individual’s diet.
Good questions, Ann. Beans are incomplete proteins because they are low in one key amino acid (amino acids are used by the body to build protein) called methionine. Cereal grains—including corn, rice and wheat—are high in methionine yet lack another amino acid found in beans.
This begs the query “Do beans have amino acids?”
I learned your body can make most of these on its own, but there are nine essential amino acids that you need to supply via your diet. Beans are a rich source of eight of those essential amino acids. But most fall short of that key ninth protein ingredient — it’s an amino acid called “methionine.”.
What foods are complete proteins?
Animal products like beef, fish, dairy, and eggs contain enough of every one of these essential amino acids. Thus, they’re considered complete proteins ( 2 ).
A complete protein has all nine of these essential amino acids, not least because for protein synthesis and muscle creation in the body, all nine are necessary. Examples of complete proteins are eggs, chia seeds, Greek yogurt, quinoa, and soybeans.
These are incomplete sources of protein, and they include: Legumes (beans, peas, lentils)., and whole grains. Complete proteins contain all nine essential amino acids in consistent amounts.
How much protein is in rice and beans?
In a 1-cup serving of rice and beans you can gain a complete protein content of 7 grams. This meal choice is also a great way to load back up on carbs and protein after a workout.