Nutritional quality of the traditionally cooked Zamnè, a wild legume and a delicacy in Burkina Faso: assessment of the process effectiveness and the properties of cooking alkalis

Zamnè is a wild legume and a famine food that attracts interest for its health benefits and has become a delicacy in Burkina Faso. This study aimed to determine the nutritional quality of the traditionally cooked Zamnè, appreciate the effectiveness of the traditional cooking process, and compare the properties of the traditionally used cooking alkalis (i.e., potash or plant ash leachate and sodium bicarbonate). Yet, as shown, the traditional cooking of Zamnè is a very aggressive process that results in high disintegration of cell walls and membranes and leaching of most water-soluble constituents and nutrients (i.e., free amino acids, soluble nitrogen, sugars, soluble dietary fibers, and soluble phenolics). In addition, the extensive boiling and the cooking alkalis induced the sequestration of calcium, iron, magnesium, and zinc, significantly impairing their bioaccessibility. Despite the difference in the modus operandi of the cooking alkalis, there was no significant difference in the cooking outcomes. The traditionally cooked Zamnè presented high dietary protein (4.8 g), lipid (3.3 g), fiber (6.7-7.7 g), and metabolizable energy (63-65 kcal) contents (per 100 g fresh weight). Most antinutritional factors (i.e., non-protein nitrogen, tannins, and trypsin inhibitors) were eliminated. The proteins were relatively well preserved despite the aggressive alkaline processing. They demonstrated an appreciable digestibility (75%) and predicted PER (1.5) and a fairly balanced essential amino acid composition - which should completely meet the requirements for adults. The lipid content and composition were also well preserved and contained predominantly linoleic (C18:2n-6), oleic (C18:1c9), stearic (C18:0), and palmitic (C16:0) acids (33, 34, 10, and 15% total fatty acids, respectively). Overall, though extensive alkaline cooking seems a straightforward option to overcome the hard-to-cook problem of Zamnè, processing alternatives might be useful to reduce nutrient losses, improve the digestibility of the final product, and capture its full nutritional value.

Non-Sensory Perception and Sensory Appeal of Zamnè, PseudoZamnè, Traditionally Cooked Senegalia erythrocalyx Seeds, and Tempeh According to Burkinabe Consumers

The lack of adequate knowledge of the culinary and sensory properties of most indigenous and wild foods hampers their promotion in human diets and the market. In the present study, 80 Burkinabe volunteers evaluated the sensory appeal and attributes of three selected Senegalia seed species (Zamnè, pseudoZamnè or Kumatiya, and S. erythrocalyx) and their food formulae (traditionally cooked, harvested as green and fresh legumes, and fermented as tempeh) using the nine-point hedonic scale and check-all-that-apply questionnaire. They found that the traditionally cooked Zamnè, pseudoZamnè or Kumatiya, and derived tempeh had good sensory appeal (scoring between 5 and 7) and subtle alkaline and nutty tastes. However, an appreciable number (32%) of the participants were unaccustomed to tempeh and gave very low scores (2.5-3.4) for all the tempeh products. In contrast, the traditionally cooked seeds of Senegalia erythrocalyx and the green and fresh Zamnè evoked bitter and sour off-tastes, respectively, and were not much appreciated (scoring 4). The present study provides unprecedented insight into consumers' non-sensory perceptions and the culinary and sensory properties of Senegalia seed foods, which will be essential for their valorization, branding, and marketing.