Cowpeas, unripe seeds, raw (snake beans, organic?)

The cowpea ( Vigna unguiculata ), also known as the cow bean, owes its name to the characteristic black spot around its white navel, which looks like an eye. The seeds can be prepared raw or cooked like garden beans . Make sure they are organic .

Use in the kitchen

Cowpeas have a wide variety of uses in the kitchen. Green, unripe pods are particularly tender and less fibrous. At this stage, it is difficult to separate the seeds from the pods as they are not yet fully ripe. The individual seeds are used raw and cooked (see prepared cooked cowpeas ) or the whole pod is used as a green vegetable, similar to green beans . Yellow, ripe pods are ideal for shelling and if you prefer plump seeds with a high water content. They can be cooked quickly (10 minutes) in a saucepan or frying pan with a lid and then enjoyed. Brown pods indicate that the bean seeds are fully ripe and starting to dry out. Fully dried beans must be soaked and boiled for 30 minutes or longer (partly because of the antinutrients they contain) before they can be enjoyed. ¹ The leaves of the cowpea are also edible and can be eaten in a similar way to spinach . ²

Can you eat cowpeas raw? Unripe, green cowpeas are often mentioned as a raw ingredient in various recipes. However, there are different opinions regarding the consumption of raw cowpeas. It is believed that young seeds and pods contain lower amounts of antinutrients than ripe beans. ³ It is important not to confuse them with the raw poisonous common bean . We do not have any values for the tolerable amounts of raw cowpeas. Raw cowpeas may not necessarily be well tolerated by everyone. More details in the chapter "Danger - Intolerances - Side Effects".

Cowpeas are often found in salads, both raw and cooked, together with bell peppers, cucumbers and cocktail tomatoes, as well as bitter-tasting rocket and radicchio . Cowpeas can also be used to make excellent patties, falafel or bean burgers . They are also suitable for making a dip or bean sauce. As a plant-based protein source, cowpeas are an ideal ingredient in hearty soups, curries or stews, for example with tomatoes, yellow bell peppers, chili peppers, corn, spinach or chard .

The dried seeds of the cowpea can be processed into flour. You can also soak them in water and grow sprouts from them. You can find out more about sprouting under the ingredient mung bean sprouts, sprouted lentils or sprouted buckwheat .

Vegan recipe for black-eyed pea salad

Ingredients: 400g fresh black-eyed peas or alternatively 200g dried black-eyed peas, 2 carrots, 1 red bell pepper, 2 green chili peppers (as needed), 70g green olives, 1/4 bunch of parsley, 2-3 stalks of savory (or mountain oregano), 4-6 tbsp white wine vinegar, 4 tbsp olive oil (alternatively rapeseed oil ), salt andpepper .

Preparation: Green, unripe black-eyed peas can be used immediately, dried seeds must be soaked in cold water overnight. The next day, drain, rinse and cook in salted water for approx. 45-50 minutes until soft. Then allow to cool. Peel the carrots, quarter them lengthways and cut into pieces of approx. 0.5 cm. Cook in this form in salted water for 5-7 minutes until al dente, drain and allow to cool. Wash the bell peppers and chili peppers, halve them, remove the seeds and cut into thin strips. Cut the olives into slices, wash the herbs and shake them dry, pick off the leaves and chop finely. Mix the vinegar, oil, salt and pepper to make a vinaigrette and mix with the cooled, prepared ingredients in a large bowl. Cover the salad and allow to steep for approx. 1 hour. Season again with vinegar, salt and pepper before serving.

Vegan recipes with black-eyed peas can be found under the note: " Recipes that have the most of this ingredient ".

Purchasing - Storage

Raw black-eyed peas are relatively difficult to obtain in Europe. Alternatively, you can buy seeds or young plants and grow them yourself. Dried and cooked beans in jars and tins can sometimes even be purchased in organic quality. They are available all year round . You can buy them at Migros, Kaufland, specialty shops and organic supermarkets such as Alnatura and Denn's Biomarkt . Other major retailers such as Coop, Volg, Edeka, Rewe, Spar, Aldi, Lidl, Denner, Hofer and Billa rarely stock black-eyed peas and if they do, then only as special offers.

Fresh cowpeas are harvested between July and September, depending on the time of sowing. ^4,5,6 For dry bean seeds, the harvest season shifts to autumn. ²⁸ However, due to imports, often from Africa, they are often available all year round.

If you want to grow cowpeas yourself, you can buy seeds from garden departments or online. You can find out how to grow your own fresh cowpeas in the 'Growing your own' chapter.

The availability of cowpeas varies depending on the size of the store, catchment area, etc. You can find our recorded food prices for the DA-CH countries above under the ingredient image - and by clicking you can see their development at various suppliers.

Storage tips

Fresh black-eyed pea seeds can be stored in the refrigerator for about 1-2 weeks. It is also possible to blanch the seeds and freeze them. Dried seeds can be stored for up to a year, or longer under ideal conditions.

Ingredients - Nutritional values - Calories

What nutritional values do black-eyed peas have? Raw black-eyed peas contain 90 kcal/100g and 77% water. Per 100g of beans they have 3g of protein and 19g of carbohydrates . The fat content is low at 0.35g/100g. They are rich infiber at 5g/100g. This corresponds to 20% of the daily requirement.

Folic acid occurs in pulses as a precursor in the form of folate (folic acid-active substance group): the folate content in cowpeas is 168 µg/100g, which corresponds to 84% of the daily requirement. This puts them on a par with dried shiitake mushrooms, which have 163 µg/100g of the vitamin. Cooked cowpeas have 127 µg of folate per 100 g. A particularly rich source of folate with 423 µg/100 g are fava beans, which can be eaten raw. Mung beans (625 µg/100g), borlotti beans (604 µg/100g) and chickpeas (557 µg/100g) also contain a lot of folic acid. However, these have to be cooked, which reduces the folic acid content, as it is a water-soluble vitamin.

The manganese content Beans contain 0.56 mg/100g, which makes up 28% of the daily requirement. Similar values can be found in parsnips (0.56 mg/100g), horseradish (0.5 mg/100g) and kale (0.66 mg/100g). Almonds contain four times this amount (2.2 mg/100g). Pine nuts (8.8 mg/100g) and wheat germ (13 mg/100g) provide particularly high levels of the trace element.

Potassium is also plentiful at 431 mg/100g. This covers 22% of the daily requirement. Cooked kidney beans contain a comparable amount at 405 mg/100g. Broad beans, which can be eaten raw, contain significantly more of the mineral at 1,062 mg/100g. There is also plenty of potassium in lamb's lettuce (459 mg/100g), cooked soybeans (515 mg/100g) and spinach (558 mg/100g). Bananas, which are often cited as a good source of potassium, only contain 358 mg/100g. ⁷

The complete ingredients of cowpeas, the coverage of the daily requirement and comparison values with other ingredients can be found in our nutrient tables. In the article Nutrients explained you will get a detailed insight into the topic.

Effects on health

Are cowpeas healthy? Cowpeas are considered to be a nutrient-rich food with a low energy density. They are characterized by a relatively low fat content and a high total protein content. The total protein content of cowpeas is about two to four times higher than that of grains and tubers. ²

The legumes are ideal for a vegan and vegetarian diet. Not every plant-based protein source contains all essential amino acids in sufficient quantities. However, the combination of legumes and grains can lead to a balanced amino acid composition. Compared to grains, cowpeas, for example, contain significant amounts of lysine, which is ideally complemented by grains such as millet or spelt with a low lysine concentration. On the other hand, cowpeas lack the amino acids methionine and cysteine, which are abundant in many grains. This means that all essential amino acids can be adequately covered in the diet. ^8,9

In addition, a diet high in legumes can reduce the risk of heart disease and lower blood pressure and heart rate. These results come from an American study published in the Archives of Internal Medicine . ¹⁰

Beans, including the cowpea, are rich in soluble and insoluble fiber. ^7,8 A high fiber content promotes digestion, contributes to optimal intestinal health and reduces the risk of colon cancer. The fiber increases stool volume and stimulates intestinal activity, which prevents constipation. ^8,11,12 Fiber-rich foods reduce blood cholesterol levels by reducing the reabsorption (reuptake) of bile acids. ^8,11 They also promote a feeling of satiety, which helps prevent obesity. ² You can read more about this inour article on fiber .

Cowpeas have a low GI (glycemic index) due to the resistant starch and fiber they contain. Studies show that the GI of cowpeas ranges from 29-61, depending on the variety. A low GI value is typically below 55. With the exception of one cowpea variety, which had a GI of 61.57, the values of the other five specimens examined were below 55. ⁸ Eating foods with a low GI can prevent the development of obesity, diabetes, cardiovascular disease, and certain types of cancer. ² Cowpeas are also very suitable for diabetics, as their carbohydrates are absorbed into the blood very slowly, thus keeping blood sugar levels constant.

Other health-promoting components of cowpeas are alpha-galactosides. These are oligosaccharides (carbohydrates), including raffinose and stachyose, which have a prebiotic effect. ² Prebiotics promote the growth and activity of beneficial bacteria in the intestine, which has a positive effect on intestinal health. However, these compounds can also cause flatulence. ^2,13 More on this in the chapter "Danger - Intolerances - Side Effects".

In addition, cowpeas supply the body with important minerals and vitamins such as potassium, manganese, calcium and B vitamins, including folic acid, thiamine and riboflavin . ^2,7,8 Potassium has a positive effect on blood pressure and helps regulate hypertension (high blood pressure). This can reduce morbidity and mortality from cardiovascular diseases. ¹⁴ Folic acid is involved in the division, formation and regeneration of cells as well as in blood formation. Humans also need the vitamin for the metabolism of certain amino acids, such as homocysteine breakdown. An adequate supply of folic acid is particularly necessary during pregnancy to ensure normal development of the fetus. ¹⁵ The vitamin B1 (thiamine) they contain means that legumes make a valuable contribution to supporting healthy nerve function and energy metabolism. ¹⁶

Secondary plant substances

Many of the health effects of cowpeas can be attributed to the secondary plant substances they contain. Our article on secondary plant substances provides an overview of the classification of substance groups, their occurrence in foods and possible effects on humans. Cowpeas contain the following secondary plant substances, among others: ^9.17

• Isoprenoids
• Polyphenols
• Protease inhibitors: trypsin inhibitors, chymotrypsin inhibitors, lectins, phytic acid, oxalic acid

However, it should be noted that the composition of secondary plant substances in cowpeas can vary depending on the variety, time of harvest and growing conditions. Therefore, quantities are only of limited use and should only be understood roughly.

For example, flavanols (tannins), unlike flavonols, which occur in all cowpea varieties, are only present in certain phenotypes. They have been found in red and light brown cowpeas, but are absent in the white ones. ¹⁷ Tannins have anti-cancer properties, but are also considered anti-nutritional. More on this in the chapter "Danger - Intolerances - Side Effects".

Bean seeds are a good source of phenols, mainly phenolic acids, flavonoids, anthocyanins and proanthocyanidins. Polyphenols are concentrated in the seed coat, which is why unpeeled seeds are preferable. ⁹ The seed coat has 5 to 10 times more phenols than the seeds, and 10 times more flavonoids. ⁸

The phenolic compounds are responsible for the antioxidant properties of the cowpea. Antioxidant substances act as radical scavengers and thus protect against oxidative damage and stress. Antioxidants play an important role in the prevention of degenerative diseases in humans, including arthritis, Alzheimer's and diabetes. Oxidative stress is a significant risk factor for the development of various types of cancer. In addition to phenolic compounds, saponins and phytates help protect against cellular damage and thus have an anti-cancer effect. ⁸

The antioxidant effect can be further enhanced by germination. Studies have reported that the antioxidant capacity of cowpeas increases by 50–60% through the germination process. The content of beta-carotene, phenols and flavonoids also increases. On the fifth day of germination, a three-fold increase in the total phenol content was recorded in germinated cowpeas compared to the ungerminated seeds. ⁸

Phenols are strong inhibitors of alpha-amylase and alpha-glucosidase, two important enzymes involved in the regulation of blood sugar (glucose homeostasis). This gives the cowpea antihyperglycemic, antidiabetic and blood sugar stabilizing properties, among others. ^2,8,17 The phenolic components also have antihypertensive (blood pressure lowering), anti-cancer, cholesterol-lowering and anti-inflammatory effects. ^8,17

Studies show that phenols contained in cowpea protect human low-density lipoprotein (LDL) from copper-induced peroxidation. Oxidized LDL plays a role in the development of coronary heart disease by leading to the formation of fatty streaks (deposits on the artery walls) and consequently to arteriosclerosis (hardening of the arteries). In particular, the flavonoid glycosides of quercetin (quercetin 3-O-beta-D-sophoroside, quercetin 3-O-beta-D-glucopyranosyl-(16)-O-beta-D-galactopyranoside) and catechin (catechin 7-O-beta-D-glucopyranoside) show a significant inhibition of LDL oxidation. This finding underscores the hypocholesterolemic (cholesterol-lowering) potential of cowpeas as natural antioxidants to support heart health. ^8,17

Dangers - Intolerances - Side effects

Cowpeas contain anti-nutrients that inhibit the bioavailability of minerals. Phytic acid interacts with macro- and micronutrients by binding important divalent cations such as iron, zinc, calcium or magnesium . This binding creates insoluble complexes that impair mineral absorption and utilization during digestion. ⁹ Phytic acid also offers health benefits, particularly in relation to its anti-cancer properties. You can find out more about this in the article Phytic acid or phytate and soaking or sprouting .

Other anti-nutritional factors in cowpeas besides phytic acid are: tannins, lectins, protease inhibitors (trypsin inhibitors and chymotrypsin), oxalic acid and oligosaccharides. For example, tannins reduce the digestibility of proteins and carbohydrates by inhibiting digestive enzymes and forming complexes with them. The trypsin inhibitors contained in cowpeas reduce trypsin activity, thereby limiting the digestion and absorption of proteins. Oligosaccharides, including raffinose, stachyose and verbascose, are carbohydrates that do not cause any health disadvantages. However, consumption of oligosaccharides present in beans leads to gas formation in the intestines, resulting in flatulence. Soaking, cooking, sprouting and genetic modification of the plant help to minimize the flatulence factor. ⁹

Lectins, which are non-specifically called hemagglutinins, phytohemagglutinins or PHA, also interfere with the digestion and absorption of nutrients. One well-known lectin is phasin, which has been established as a collective term for certain lectins discovered in the common bean ( Phaseolus vulgaris - hence the name). According to the Poison Information Center of the University Hospital Bonn ( UKB ), phasin is considered toxic and can lead to poisoning. Phasin is also found in high concentrations in bean species closely related to the common bean. ¹⁸ However, we were unable to find any confidential information on phasin in cowpeas.

A 2021 study measured lectin activity in various plant foods using a hemagglutination test. No activity was detected in adzuki beans, barley, chia seeds, cowpeas, eggplant, green peppers, hemp seeds, flax seeds, mung beans, sesame seeds, urd beans and wheat. However, it should be noted that this test worked in vitro with rabbit blood. Since the research is very contradictory, the authors of the study emphasize the need for further research. ¹⁹

Studies show that the tannin profile of cowpea is also different from that of other legumes. The antinutritional properties of tannins depend on their structure and molecular weight. Tannins with higher molecular weight are far more efficient at binding nutrients. In cowpea, glycosylated monomers, which have a lower molecular weight, dominate. The glycosylation and low molecular weight have a positive effect on the bioavailability of the flavanols in cowpea. Therefore, it is assumed that the overall adverse effects of cowpea tannins on the digestion and absorption of nutrients are likely to be small. In vivo data, which are limited, also show no significant effect of cowpea tannins on protein digestibility and absorption. ¹⁷

There are differing views and confusion regarding raw consumption. A comparative study showed that immature cowpea seeds have a lower concentration of trypsin inhibitors than mature seeds. Based on these results, it is assumed that young seeds and pods contain lower amounts of antinutrients than mature beans. ³

Studies have shown that the content of antinutrients is subject to considerable fluctuations and, in the case of cowpeas, is proven to depend on the variety. ¹⁷ Current research results show that new breeding lines can be used to specifically minimize the content of antinutrients, in this example phytic acid. ²¹ Germination, fermentation, peeling and cooking also reduce the antinutrients and have a positive effect on the bioavailability of the ingredients. ^2,3

Although research does not classify raw cowpeas as toxic, unlike raw kidney beans, for example, which have particularly high lectin levels ²⁰, we recommend keeping raw consumption to a minimum due to the anti-nutrients they contain. We do not have precise information on the effects of consuming large amounts of raw cowpeas on the human body. Further research is needed to classify raw consumption as safe and harmless.

The following legumes are definitely non-toxic when raw and edible in normal quantities: green peas, sugar snap peas and peanuts .

Danger of confusion

Cowpeas come in different colors (phenotypes): They can be white, cream, green, red, brown, black or spotted. ⁹ They should not be confused with varieties of the common bean ( Phaseolus vulgaris ), including black beans, kidney beans or white beans . These contain pasin and should therefore not be eaten raw. There is also a risk of confusing the young pods of the cowpea with those of the common bean.

Folk medicine - natural healing

Various West African tribes (Hausa and Yoruba) use the plant for spiritual and medicinal purposes. The leaves and seeds are used as a poultice for skin infections. The leaves can be chewed to relieve toothache. Powdered, charred seeds are applied to insect bites. The roots are used to treat epilepsy, chest pain, constipation and as an antidote for snake bites. ²²

Ecological footprint - animal welfare

The ecological footprint of a food depends on various factors. The type of agricultural production (conventional vs. organic), seasonal, regional, domestic production or import by truck, ship or plane, different types of packaging and whether the goods are fresh or frozen all play a decisive role. ²³

According to the Canadian organization HEALabel, the _carbon footprint of cowpeas is 0.56 kg CO ₂ eq/kg, but there is no precise information available on the breakdown of this value. ²⁴ For comparison: fresh sugar snap peas have a _carbon footprint of 0.4 kg CO ₂ eq/kg. The value for green beans is 0.8 kg CO ₂ eq/kg and for dried lentils it is 1.2 kg CO ₂ eq/kg. In contrast to meat, pulses produce significantly fewer CO ₂ emissions: the average ecological footprint of beef is 61.04 kg CO ₂ eq/kg. ²³

The country of origin plays an important role in calculating the ecological footprint. Local, organically grown beans are preferable, as the goods imported from Africa and Asia have to travel long distances. The resulting transport-related emissions can increase the value of the _carbon footprint. For the ingredient pineapple, we explain the influence of the various means of transport, such as ships and aircraft, on the size of the footprint.

The water footprint of cowpeas is estimated at 6906 l/kg. ^24,25 However, this study is based on dried seeds. We do not have any data on fresh cowpeas. However, due to an earlier harvest, it can be assumed that they use less water than the mature specimens.

In addition to being used as a main crop, cowpeas are also used as intercrops or as green manure. Legumes are popular with main crops such as millet, corn or cantaloupes because they enrich the soil with organic components. ^26,27,28 Green manure is not only important for many ecosystems, but also for agricultural soils. As legumes, they can form a symbiotic relationship with nodule bacteria. These fix nitrogen from the air and make it available to the plant. Thanks to their nitrogen-fixing potential, cowpeas require little or no nitrogen to grow. As a result, environmentally harmful nitrogen fertilizers can be avoided during cultivation. ²

For detailed explanations of various sustainability indicators (such as ecological footprint, _CO2 footprint, water footprint), see our article: What does the ecological footprint mean?

Worldwide occurrence - cultivation

The origin of the black-eyed bean is thought to be in Africa. Today it can be found worldwide. The cowpea is grown in Africa, South America, the USA, Mexico, Australia and Asia. Although the legume is hardly widespread in Europe, it is occasionally found in the Mediterranean region, such as Spain, Italy, Portugal, Greece and Cyprus. ^2,8 Africa, along with Nigeria and Niger, is the world leader in the production of cowpeas. ⁹

Found in the wild

The cowpea ( Vigna unguiculata ) comprises 13 officially recognized subspecies. ²² These include the two cultivated bean species, the catjang bean ( Vigna unguiculata ssp. cylindrica ) and the asparagus bean ( Vigna unguiculata ssp. sesquipedalis ). Vigna unguiculata ssp. unguiculata refers to the cultivated cowpea, while the subspecies ssp. dekindtiana and ssp. menensis are considered related wild forms. ^22,29

Cultivation - Harvest

The cowpea is an annual plant that has different growth forms: the plant can grow upright, hanging, climbing or bushy. ^5,9 It has a taproot system with lateral roots that spread out on the surface of the soil. The cowpea, like the asparagus bean, is a very tolerant plant to heat and drought. ⁹

The leaves are alternate and trifoliate, except for the first pair of leaves, which are basal and opposite. The shape of the leaves varies from linear-lanceolate to ovate. The flowers are white, yellowish, pale blue or purple and appear in racemose inflorescences. The pods of cowpeas are typically long, slender and slightly curved (crescent-shaped). Young, fresh pods are green in color. As they ripen, they can turn brownish. The pods are usually 20-30 cm long and have small seeds. ⁹

Growing your own seeds

If you want to grow them in your own garden, you can buy them either online or in a garden center. When sowing, make sure you choose the right time. As the plant is sensitive to frost, you should wait until the last frost before planting the seeds outside in the soil. ^4.5 To do this, plant them at intervals of about 5-8 cm and 1-1.5 cm deep. ⁵ Alternatively, you can grow them as seedlings indoors for 4 weeks, although they are often sensitive to transplanting. ⁴

After about 60-100 days, the black-eyed peas can be harvested. The harvest time varies depending on the preferred degree of ripeness. For raw consumption, harvesting is recommended when the young pods are plump but still tender. This is approximately after 60 to 70 days (or sooner) if they are green in color. If you want to harvest black-eyed peas for the dried seeds, the pods should have reached a brown color and a growth period of 90 days should have passed. ⁴

Further information

The cowpea is a legume (Fabaceae). The plant belongs to the Faboideae family. Cowpeas do not belong to the South American Phaseolus or Vicia, but rather to the legume genus Vigna . This includes around 100 subtropical species that are mainly found in Africa and Asia. Nine of these Vigna species have been domesticated, two of them in Africa and seven in Asia. The African Vigna is divided into the Cowpea ( Vigna unguiculata ) and the Bambara groundnut ( Vigna subterranea ). The Asian Vigna includes the mung bean ( Vigna radiata ), the urd bean ( Vigna mungo ), the moth bean ( Vigna aconitifolia ), the azuki bean ( Vigna angularis ), the rice bean ( Vigna umbellata ) as well as Vigna trilobata and Vigna reflexo-pilosa . ³⁰

Alternative names

The cowpea is called the black-eyed bean because of the characteristic black spot around its white navel, which looks like an eye. Other names are cowpea, snake bean, cow bean, customer bean or long bean. The term snake bean sometimes also refers to the related asparagus bean, which can lead to confusion. In English it is called cowpea, black-eyed pea, bachapin bean, southern pea, crowder pea, China pea and cow gram. ⁹

Other uses

In Nigeria, cowpea is also grown for its strong plant fibers, which are used to make fishing gear and high-quality paper. The dried seeds are a good alternative to coffee. ²²