Protein in Black Beans: Per Cup, Can and 100 g

The protein in black beans makes them one of the cheapest, easiest ways to add plant protein to your diet. A cup of cooked black beans has about 15 g of protein, along with a huge 15 g of fibre and plenty of folate, iron and magnesium. A drained can gives you roughly 17 to 19 g. This guide covers the numbers for cooked, canned and dried beans, how they compare with other proteins, and how to build black bean meals with 30 g of protein or more.

Black bean protein by serving

Values come from USDA FoodData Central for black beans boiled without salt, and typical canned bean labels.

Dried beans look much higher in protein per 100 g, but that's only because they haven't absorbed water yet. Dried black beans roughly double to two-and-a-half times their weight when cooked, so 100 g dried makes about 230 to 250 g cooked. The raw to cooked weight calculator can help with conversions.

Canned vs cooked from dry

Canned black beans have slightly less protein per 100 g than home-cooked beans, about 6 to 7 g drained, because they're cooked in more liquid. They also contain much more sodium, often 300 to 500 mg per half cup. Draining and rinsing can cut sodium by up to 40%, according to the American Heart Association, which also suggests choosing low-sodium or no-salt-added canned foods.

Other nutrients in black beans

A cup of cooked black beans also provides:

• Folate: around 64% of the daily value.
• Magnesium: around 29%.
• Iron: about 3.6 mg, around 20%. Eating beans with vitamin C, such as tomato, peppers or lime, improves absorption of plant iron.
• Potassium: around 600 mg.
• Almost no fat: under 1 g.

The fibre is the big standout. Most adults eat far less than the recommended 25 to 38 g of fibre a day, and one cup of black beans covers more than a third of that. The Harvard T.H. Chan School of Public Health links regular legume intake with better heart health and blood sugar control.

Black beans vs other protein foods

Black beans sit in the middle of the legume pack. Lentils and edamame have a little more protein per calorie, and soy foods like tofu have much more. See our guides to lentil protein, chickpea protein, edamame protein and tofu protein for the details.

Black beans vs refried beans

Traditional refried beans are usually made from pinto beans, mashed and cooked with fat. Per half cup they have about 6 to 7 g of protein, similar to whole beans, but often more fat and sodium. Fat-free or vegetarian refried beans are closer to plain beans nutritionally.

Are black beans a complete protein?

Legumes are rich in lysine but low in methionine. Grains are the opposite. That's why classic pairings like rice and beans, or beans with corn tortillas, give you a fuller range of amino acids. You don't need to eat them in the same meal, because your body pools amino acids over the day. The Academy of Nutrition and Dietetics notes that vegetarians who eat a variety of plant proteins through the day can meet their needs.

How to get 30 g of protein from a black bean meal

Beans alone would take about two cups to hit 30 g, which is a lot of food and around 450 calories. It's easier to pair them with a second protein source:

• Black bean and egg breakfast burrito: ½ cup beans, 2 eggs, cheese and a tortilla. About 30 g protein.
• Burrito bowl: 1 cup beans, 100 g chicken or tofu, rice and salsa. About 45 g with chicken, 33 g with tofu.
• Black bean soup with Greek yogurt: 1½ cups beans topped with 100 g Greek yogurt. About 32 g. More ideas in high-protein soup.
• Black bean burgers with TVP: adding rehydrated TVP to the mix lifts protein and helps the patties hold together. See our TVP recipes.
• Bean and quinoa salad: 1 cup beans plus 1 cup cooked quinoa gives about 23 g, and feta or edamame takes it past 30. See quinoa protein.

You can work out your own per-meal target with the protein per meal calculator.

Cooking dried black beans

1. Rinse and pick out any small stones.
2. Soak overnight in plenty of water, or use a quick soak: boil for 2 minutes, then leave covered for an hour.
3. Drain, cover with fresh water by about 5 cm and simmer for 60 to 90 minutes until creamy inside. A pressure cooker takes about 20 to 25 minutes after soaking.
4. Salt towards the end, or add a little at the start if you like; both work.
5. Freeze cooked beans in their liquid in portions for quick meals.

Cooking from dry costs a fraction of canned beans and lets you control the salt. Our cheap high-protein meal prep guide uses a batch of beans across several meals.

Black beans for camping and backpacking

Canned beans are too heavy for backpacking, but there are good lightweight options:

• Dehydrated black beans or instant refried bean flakes rehydrate in 5 to 10 minutes with hot water.
• Home-dehydrated beans: cook, spread on trays and dry until hard. See dehydrating food for backpacking.
• Pair with tortillas, cheese and rice for a filling trail burrito.

Instant bean flakes have around 20 g of protein per 100 g dry and pack a lot of calories for their weight. Find more ideas in our backpacking dinner ideas.

Do black beans cause gas?

They can. Beans contain oligosaccharides, sugars your gut bacteria ferment. Soaking dried beans, discarding the soaking water, rinsing canned beans and increasing your intake gradually over a couple of weeks all help. Most people find the effect gets smaller as they eat beans more regularly.

Black beans on a budget

Black beans are among the cheapest protein foods you can buy, especially dried. Compare the cost per gram of protein with other foods using the protein cost calculator, and see our full list of cheap high-protein foods.

Bottom line

Black beans have about 15 g of protein per cooked cup, 9 g per 100 g and 17 to 19 g in a drained can, plus a big dose of fibre. They're not as protein-dense as soy or meat, so pair them with eggs, dairy, tofu, chicken or grains to build a high-protein meal. Rinse canned beans to cut sodium, or cook a batch from dry for the cheapest protein in the store.

Sources: USDA FoodData Central; Harvard T.H. Chan School of Public Health, legumes and pulses; Academy of Nutrition and Dietetics, tips on switching to a meatless diet; American Heart Association, how to reduce sodium.