Cowpea Immature Pods and Grains Evaluation: An Opportunity for Different Food Sources

Abstract

Currently, the sustainability of agro-food systems is one of the major challenges for agriculture and the introduction of new pulse-based products can be a good opportunity to face this challenge. Cowpea (Vigna unguiculata L. Walp.) is a nutritionally important crop and has the particularity that the aerial section of the plant is entirely edible. The current research determines the nutritional composition of the alternative cowpea food sources immature pods and grains comparatively to dry grains through the evaluation of protein, minerals and different polyphenolic contents, and antioxidant capacity. Ten cowpea genotypes were analyzed during two harvest seasons. Cowpea immature pods and grains revealed high levels of total protein and K, Ca, Zn and Fe contents. In general, most of the genotypes produced cowpea of high nutritional value, with a high variation observed between them. Our results showed the potential of the introduction of new cowpea new products in the market allowing a healthy and variable diet and at the same time a better use of the crop under the scenario of climate change.

Cowpea Constraints and Breeding in Europe

“…In total, cowpea corresponds to the 0.3% of pulses production in Europe and the 0.3% of world cowpea production for dry seed, reaching up to 23,825.22 ton in 2021 [ 58 , 60 ]. However, not many data are available regarding cowpea production for fresh pod production despite that its production was enhanced in Southern European countries lately [ 10 , 61 ].…”

“…Cowpea faces a multitude of biotic and abiotic factors that negatively affect its productivity worldwide [ 172 ]. In Europe, the cowpea cultivation area is increasing [ 10 ] as it is considered a drought- and high-temperature-tolerant plant species in comparison to other legumes. Recently, cowpea fresh pods and green seeds started to be investigated as new products for the market [ 10 ], while more intense efforts are made to increase pulse production and grain-legume-based products in Europe [ 173 ].…”

“…Food dishes containing cowpea leaves especially are characterized by extremely high Fe and Ca levels [ 342 ]. Recently, in Europe the consumption of high protein vegetables, such as cowpea, is intensively promoted [ 10 ]. Cowpea is characterized by high seed protein content even higher than 30% [ 343 , 344 ] and low-fat content as well as a significant concentration of carbohydrates [ 3 , 345 ].…”

“…Padhi et al [ 345 ], evaluating 120 cowpea genotypes, found remarkable variability among them regarding their proximate composition. Proximate and nutrient composition of cowpea fresh pods and seeds have been found to be strongly affected by environment [ 15 ] and genotype [ 346 , 347 , 348 ], while a genotype x environment interaction is also usually present [ 10 , 174 , 349 ]. Cooking methods and food processing are also reported to drastically affect cowpea nutrient content [ 3 , 350 ], e.g., fermentation of cowpea flour was found to improve P availability and Mg digestibility [ 351 ].…”

“…Almost all its above-ground plant parts are consumed [ 6 ]. In addition to its mature dry seeds, its leaves, green pods and green seeds are consumed in various countries [ 5 , 7 , 8 , 9 , 10 ]. It is also used for flour [ 3 , 11 , 12 , 13 ], as its seeds contain a high protein content (23–32%) compared to many other legume species [ 14 , 15 ].…”