Legumes and pulses
Legumes are plants that have their seeds arranged within pods. When the seeds are removed from the pods they are called beans, lentils or peas. Examples of legumes include fresh peas, fresh beans, pulses (dried beans, lentils, peas, chickpeas, lupins, and fava beans), peanuts and soybeans.
Legumes are powerhouses of the plant kingdom and represent a great family of plants with more than 600 genera and 13,000 species.
Legumes are referred to as a “nitrogen-fixing crop” since they draw nitrogen from the air and store it in their roots. The plant releases some nitrogen in the soil, enriching it and reducing the need for chemical fertilizers. Nitrogen soil fixation also happens as part of a partnership between soil bacteria and the plant.
Pulses are part of the legume family. The term pulse refers to dried seeds such as dried beans, lentils, peas, chickpeas, lupins, and fava beans. Like legumes, pulses are nitrogen-fixing crops able to increase biodiversity, soil fertility, soil microbial biomass, and activity. Pulses can help to improve the environmental sustainability of crops and to reduce our environmental footprint.
Why should we eat it? BEANefits of eating pulses 🙂
Pulses contribute to the health of our planet, but also to ours as they are an extremely healthy food choice.
- Overall, these nutrient-dense foods are a great source of protein, , fiber, iron, zinc, magnesium, phosphorus, and folate as well as other B vitamins.
- They have virtually no fat.
- They can supply a significant amount of protein for those who do not consume or limit animal proteins – lentils, kidney beans, soybeans, and tofu have a percentage of calories from proteins similar in range as regular ground beef, eggs, cow’s milk, and cheddar cheese.
- Pulses have a low glycemic index, making them a great dietary option that can help to stabilize blood sugar and insulin levels.
- Pulses are a concentrated source of fiber (soluble and insoluble fiber).
- Pulses provide good amounts of soluble fiber, which can help to lower LDL cholesterol and to reduce the risk of cardiovascular diseases.
- Pulses are also rich in insoluble fiber, which helps move waste through the gut. Thereby, they can lower the risk of constipation, hemorrhoids, and diverticular disease.
- The resistant starch present in pulses is considered as a prebiotic food. Prebiotic foods serve as an aliment for the friendly bacteria that colonize our guts and stimulate the colon activity. Bacterial fermentation of prebiotics in the gut can promote numerous health benefits such as improving immune functions, promoting healthy digestion, supplying essential nutrients, synthesizing short-chain fatty acids (SCFA) and vitamin K, promoting new blood cells, among others.
- The phytochemicals, saponins, and tannins (found in pulses) have antioxidant and anti-carcinogenic effects, indicating that pulses may have important anti-cancer effects.
- Beans, in general, contain estrogen-like phytochemicals known as isoflavones. This substance is associated with a reduced risk of breast and prostate cancers.
- Pulses are naturally gluten-free and can enhance the nutritional profile of those following a strict gluten-free diet.
- Eating pulses instead of red meat (beef or pork) can help lower the risk of colorectal cancer, heart disease, and T2DM.
- Pulses offer interest to our diets with a rich array of tastes, colors, sizes, and shapes, consumed whole, split or ground or as an ingredient into a recipe.
- They are an inexpensive and delicious way to introduce healthy options to our and should be part of a healthy diet.
N.B.: Soybeans and peanuts differ from pulses as they have greater fat content, whereas pulses have almost none.
Tips to consider:
- Pulses are low in methionine (an essential amino acid) and cysteine (a conditionally essential amino acid), but by complementing pulses with grains (which have both of these amino acids but lack the amino acids lysine and threonine) we can potentially increase the protein quality of a meal. Note that we don’t need to consume pulses and grains at the same meal.
- To enhance iron absorption from pulses and from other vegan sources of iron, it is important to combine these foods with a source of vitamin C.
- Pulses are rich in oligosaccharides, i.e. carbohydrates that our digestive enzymes are not able to break down. Instead, they are fermented in the gut by our microbiota, which can produce gas. To increase the digestibility and reduce gas formation due to consumption of beans and chickpeas, soak these pulses prior to cooking to reduce some of their oligosaccharide content. After soaking, discard the water and rinse the seeds well. For most adults, flatulence decreases with a regular consumption of pulses. Increase the serving size of pulses gradually.
- Soaking beans also reduce the effects of phytic acid – a compound in legumes that can decrease the digestibility of starches, proteins, and fats, and can reduce the absorption of the minerals iron, zinc, and manganese.
- Soaking legumes also help to reduce lectins. Some lectins can be toxic but most are harmless as they are denatured during the cooking process.
- Avoid eating raw or under-cooked legumes such as beans and lentils as they can promote vomiting and diarrhea. Ensure to cook/boil your beans for at least 30 minutes.
- Soft legumes like lentils, split peas, and black-eyed peas must be thoroughly rinsed rather than soaked before cooking.
- Canned beans and chickpeas are convenient but they can be loaded with sodium. Rinse canned beans and chickpeas well under running water for 10 or more seconds and drain the seeds well. This simple step can help to reduce up to 40% of the sodium content of canned pulses. If you can afford, prefer to buy sodium free versions.
How to properly soak your beans?
- Prior soaking check if there are pieces other seeds or small stones.
- Wash the grains to remove residual dust.
- Cover the dried seeds completely with water and add at least 2 more cups of water. Cover and allow the beans to soak overnight.
- Reduce soaking time by boiling beans for three minutes, then remove the beans from the heat and leave them covered for two to three hours. Discard the water and rinse before cooking.
- Check the instructions on the package before soaking or cooking beans.
Protein content in pulses and legumes:
– 75 g of lean flank steak has about 26 g of protein
– 1 large egg about 6 g of protein
|Portion size||Food choice||Protein content|
|125 mL / 88 g||Tempeh*||16 g|
|150 g||Steamed regular tofu*||15 g|
|125 mL / 95 g||Cooked edamame (soybean)||12 g|
|½ cup / 104 g||Cooked lentils||9 g|
|½ cup / 91 g||Black beans||8 g|
|125 mL / 87 g||Chickpeas||8 g|
|125 mL / 90 g||Lima beans||6 g|
|125 mL / 85 g||Boiled green peas||5 g|
|125 mL / 85 g||Kidney beans||4 g|
|15 mL / 16 g||Natural peanut butter||4 g|
How to incorporate legumes and pulses in your diet?
- Give traditional ‘pasta primavera’ a twist by adding blanched handfuls of fava beans, sliced green beans, and combining them with spiralized zucchini and fresh pesto.
- Use frozen or fresh shelled organic edamame beans to prepare a dip in minutes. Pureé blanched and cooled edamame with a little Greek yogurt and mint as a lighter alternative for hummus.
- Use fresh green or yellow beans and sugar snap peas into a stir-fry.
- Minted pea pesto makes a quick and healthy topping for bruschetta. Just blend cooked peas with a handful of mint, half crushed garlic clove, and a little olive oil until smooth.
- A traditional appetizer for Brazilians is a mug of black beans seasoned with garlic and accompanied by a caipirinha (a Brazilian cocktail).
- Roast cooked chickpeas with your favorite spices for a healthy snack.
- Incorporate cooked beans into recipes, such as black bean brownie or add cooked beans into salads, soups, fritters, burgers, smoothies … the possibilities are endless…
- Mixing lentils to cooked rice makes a side dish rich in color, flavor, and nutritional value. Top it with caramelized onions for even more flavor.
- Prepare a dhal with red or yellow lentils. Cook them slowly in coconut milk (do not boil your coconut milk to prevent it to curdle) with a little ginger and garlic. Flavor the dish with garam masala and turmeric. Serve with rice and a little bit of yogurt.
Tell us how you incorporate beans into your diet… your comments are appreciated.
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