Biochemical Characterization of Seasoning Broths from Seeds of Two Spontaneous Food Plants (Ricinodendron heudoletii and Parkia biglobosa)

Ricinodendron heudelotii and Parkia biglobosa are spontaneous food plants whose seeds play a key role in the West African diet. This study evaluated the physicochemical and nutritional properties of seasoning broths. Six broths (B1-B6) were analyzed. The results revealed significant differences between broths. Formulations based on P. biglobosa seeds have a higher titratable acidity (7.0 meq.g/100 g−10.5 meq.g/100 g) than those based on R. heudelotii seeds (2.5 meq.g/100 g−2.8 meq.g/100 g). Protein levels were similar (44.57 g/100 g−50 g/100 g), but fiber and lipids varied considerably. The mineral profiles show high concentrations of K (up to 1530 mg/100 g), Ca (up to 1961 mg/100 g), and Fe (up to 51.69 mg/100 g). These data highlight the potential of the broths studied as sources of essential nutrients, and the need to consider the two spontaneous food plants used in nutrition policies in Côte d’Ivoire.  

Introduction

Spontaneous food plants play an important role in the diets of both rural and urban populations [1]. Several studies have shown the importance of organs from spontaneous food plants in food security in Côte d’ Ivoire [2], [3]. Ricinodendron heudelotii and Parkia biglobosa are two spontaneous plants that play important roles in Ivorian cuisine. Indeed, P. biglobosa is a tree with multiple uses, particularly for its pulp and seeds. The sweet pulp surrounding the seeds is used to energetic porridges and juices, while the seeds are used to produce Soumbala, a highly prized condiment [4]. Soumbala is an artisanal product rich in nutrients and polyphenols, particularly flavonoids, and is appreciated for its taste and therapeutic properties [5]. A recent study conducted in Côte d’Ivoire showed that Soumbala is one of the most widely consumed broths [6]. Ricinodendron heudelotii is a spontaneous plant of the Euphorbiaceae family whose seeds are widely used in the local diet. These seeds, commonly known as “Akpi,” are traditionally used as a condiment to flavor sauces and soups, playing a culinary role similar to that of “Soumbala” [7], [8]. They are also used in traditional medicine because of their anti-inflammatory and antioxidant properties [9].

The term “broth” refers to an ingredient in liquid, powder or cube form, obtained by prolonged cooking of meats (beef, veal, chicken) and vegetables in boiling salted water.

Seasoning broths, dominated by major commercial brands, have become essential ingredients in African kitchens [6]. Indeed, over 80% of households use them daily to enhance the taste of dishes [10]. They are flavor enhancers that, when added to food, enhance their taste properties [11]. However, these products are increasingly criticized for their composition rich in chemical additives, notably monosodium glutamate (MSG/E621), excess salts, and potentially harmful colorants such as E110 and E124, which are associated with health risks such as hypertension, diabetes, and neurological disorders [12]. Faced with these concerns, the search for under-exploited natural and local alternatives, such as spontaneous food plants, is intensifying. Therefore, the aim of the present study was to determine the nutritional characteristics seasoning broths based on Ricinodendron heudelotii “Akpi” seeds and Parkia biglobosa “Soumbala”.

Materials and Methods

Material

The material used consisted of dried Ricinodendron heudoletii (Akpi) and fermented Parkia biglobosa (Soumbala) seeds.

Sampling

Plant material was purchased from the Adjamé Commune wholesale market (Gouro market) in Abidjan, Côte d’Ivoire. This market was chosen because it is the primary site for receiving food products from all over the country.

Broth Formulation

In the laboratory, fermented P. biglobosa and dried R. heudoletii seeds were sorted and rinsed with drinking water. The samples were oven dried at 60°C for 72 h. The other ingredients used in the formulation—dried fish, shrimp, ginger, onions, and garlic—were sorted and rinsed (Fig. 1). They were then cut with a stainless steel knife and dried at temperatures ranging from 60°C to 70°C for 48 h. After drying, all products were powdered using a blender before being used in the formulation of Akpi- or Soumbala-based bouillon cubes (Fig. 2). Six different formulations were produced, including three broths based on R. heudoletii and three broths based on P. biglobosa. Broths B1, B2, and B3 contained 50%, 55%, and 60% R. heudoletii powder, respectively, whereas broths B4, B5, and B6 contained 50%, 55%, and 60% P. biglobosa powder, respectively.

Fig. 1. Other ingredients used in the formulation of seed-based broths from Ricinodendron heudelotii and Parkia biglobosa.

Fig. 2. Production diagram for broths of seed-based broths from Ricinodendron heudelotii and Parkia biglobosa.

Physicochemical Characterization of Broths

• The pH, titratable acidity, moisture, ash, fiber, and lipids were determined using the AOAC method [13]:

$$\begin{array}{r}\text{Humidity}\left(\text{\% }\right)=\frac{{\text{M}}_1-{\text{M}}_2}{{\text{M}}_1}\times 100\end{array}$$

$$\begin{array}{r}\text{Ash }\left(\text{\% }\right)=\frac{{\text{M}}_1-{\text{M}}_2}{{\text{P}}_{\text{e}}}\times 100\end{array}$$

$$\begin{array}{r}\text{Fiber }\left(\text{\% }\right)=\frac{{\text{M}}_2-{\text{M}}_1}{{\text{P}}_{\text{e}}}\times 100\end{array}$$

$$\begin{array}{r}\text{Lipids }\left(\text{\% }\right)=\frac{{\text{M}}_2-{\text{M}}_1}{{\text{P}}_{\text{e}}}\times 100\end{array}$$

• Protein determination was carried out according to the method described by BIPEA [14] using KJEDHALL. The nitrogen and protein contents were calculated according to the following formulas:

$$\begin{array}{rl}& \text{Total nitrogen content }\\ & =\frac{({\text{V}}_{\text{HCL}}-{\text{V}}_0)\times {\text{N}}_{\text{HCL}}\times 0.014}{{\text{P}}_{\text{e}}}\times 100\end{array}$$

$$\begin{array}{r}\text{Protein }\left(\text{\% }\right)=\text{nitrogen content }\times 5.70\end{array}$$

• The carbohydrate content of the samples was determined using the method described by FAO [15], based on the following mathematical expression:

$$\begin{array}{rl}\text{Carbohydrates}\left(\mathrm{\%}\right)=& 100-\mathrm{\%}(\text{proteins}+\text{lipids }\\ & +\text{humidity}+\text{ ash})\end{array}$$

• Energy values (EV) were calculated using Atwater’s and Benedict’s specific coefficients for proteins, lipids, and carbohydrates, according to the following method [16]:

$$\begin{array}{rl}\text{VE}\left(\text{Kcal}/100\text{g}\right)=& (\text{\% lipids }\times 9)+(\text{\% proteins}\times 4)\\ & +(\text{\% carbohydrates}\times 4)\end{array}$$

Mineral Characterization

The mineral composition was determined by X-ray fluorescence spectrometry (XRF) with calibration using certified standards. To this end, 4 g of broth ash, to which 1 g of binder was added, was homogenized using a vibro-grinder and then pelletized using a 10-ton hydraulic press. The sample information was then entered into XRF analysis software. The principle of XRF analysis is to bombard matter with X-rays, which then re-emit energy in the form of X-rays. The X-ray spectrum is a characteristic of the chemical composition. The elemental chemical concentrations were then determined.

Statistical Analysis

Data were entered into Excel using appropriate mathematical tools. The flat sorting method was used to determine the frequencies of the modalities for each variable studied. Several descriptive statistical parameters, such as percentages, were also used. Stata and RStudio software were used to calculate means and standard deviations and produce tables. ANOVA was used to compare means.

Results

Physico-Chemical Characteristics

The results showed that there were no significant differences between the pH values of the studied broths. They ranged from 5.22 (B5) to 6.02 (B1). On the other hand, titratable acidity levels in broths based on R. heudoletii ranged from 2.5 meq.g/100g (B3) to 2.8 meq.g/100 g (B1 and B2), while those based on P. biglobosa ranged from 7.0 meq.g/100 g (B6) to 10.5 meq.g/100g (B5).

The moisture content was significantly different, ranging from 8.2% (B4) to 11.3% (B1).

The ash content of the broths is quantitatively significant, with values ranging from 15.5 g/100 g DM (B6) to 26.83 g/100 g DM (B1).

Macronutrient Contents

Macronutrient contents are significantly different for fiber, lipids, and carbohydrates and are identical for proteins. Fiber concentrations range from 29.5 g/100 g (B4) to 49 g/100 g (B5). The lipid levels range from 8.49 g/100 g (B1) to 27.49 g/100 g (B6). The protein values range from 44.57 g/100 g (B2) to 50 g/100 g (B4). Carbohydrate levels range from 0.48 g/100 g DM (B4) to 5.5 g/100 g (B1). The resulting energy values range from 289.93 Kcal/100g (B1) to 440.65 kcal/100 g (B6) (Table I).

Table I. Physicochemical Properties of Seed-Based Broths From Ricinodendron heudelotii and Parkia biglobosa

Broths	B1	B2	B3	B4	B5	B6
Ph	6.02 ± 0.01a	5.89 ± 0.01a	5.83 ± 0.0a	5.46 ± 0.0a	5.22 ± 0.0a	5.41 ± 0.0a
Titratable acidity (meq.g/100 g)	2.8 ± 0.0a	2.8 ± 0.0a	2.5 ± 0.0a	10.0 ± 0.0b	10.5 ± 0.0b	7.0 ± 0.0b
Humidity (%)	11.3 ± 0.99a	10.06 ± 0.71a	8.3 ± 0.42a	8.2 ± 0.56b	9.01 ± 1.13b	8.7 ± 0.14b
Fiber (g/100 g DM)	45.75 ± 0.35ab	42.5 ± 0.70c	48.5 ± 0.70ab	29.5 ± 0.70d	49 ± 1.41ab	37.25 ± 0.35a
Ash (g/100 g MS)	26.83 ± 0.24b	26.66 ± 0.0ab	26.33 ± 0.0ab	15.66 ± 0.0ab	15.83 ± 0.24ab	15.5 ± 0.71a
Lipids (g/100 g DM)	8.49 ± 0.23b	13.27 ± 0.24bc	11.33 ± 1,41c	25.66 ± 0,0a	25.99 ± 0,47a	27.49 ± 0.23a
Protein (g/100 g DM)	47.88 ± 0.09a	44,57 ± 0.09a	49.34 ± 0.04a	50 ± 0.01a	46.76 ± 0.12a	45.59 ± 0.23a
Carbohydrates (g/100 g DM)	5.5 ± 1.36b	5.44 ± 0.56c	4.7 ± 0.95c	0.48 ± 0.58a	2.41 ± 1.72ab	2.72 ± 0.56ab
Energy (Kcal/100g)	289.93 ± 3.75a	315.47 ± 4.03b	318.13 ± 8.77b	432.86 ± 2.26ab	430.65 ± 3.12ab	440.65 ± 3.43ab

Mineral Characteristics

Mineral analysis revealed high concentrations of macroelements including sodium (Na), magnesium (Mg), potassium () and calcium (Ca). Sodium (Na) and Potassium (K) concentrations ranged from 111.63 mg/100 g (B6) to 206.6 mg/100 g (B3 broth), and from 719.07 mg/100 g (B6) to 1530.33 mg/100 g (B). Thus, the Na/K ratio ranges from 0.12 (B1) to 0.16 (B6). Magnesium (Mg) and calcium (Ca) are present at interesting concentrations in our broths. They range respectively from 100.4 mg/100 g (B5) to 842.63 mg/100 g (B3) and from 1536.33 mg/100 g (B1 broth) to 1961.47 mg/100 g in B4 broth (Table II).

Table II. Macro-Element Composition of Seed-Based Broths From Ricinodendron heudelotii and Parkia biglobosa (mg/100g)

Broths	B1	B2	B3	B4	B5	B6
Na	147.73 ± 0.11a	200.83 ± 0.87a	206.6 ± 0.35a	140.17 ± 0.06a	122.27 ± 0.378a	111.63 ± 3.11a
Mg	350.97 ± 0.11a	650.23 ± 0.11a	842.63 ± 0.11a	154.23 ± 0.32a	100.4 ± 0.43a	135.5 ± 0.0a
K	1191.67 ± 0.58a	1373.33 ± 0.58a	1530.33 ± 0.58a	1012 ± 1.73a	881.67 ± 7.23a	719.07 ± 0.251a
Ca	1536.33 ± 3.05a	1553 ± 0.0a	1797.67 ± 2.31b	1961.47 ± 8.43c	1764.33 ± 0.23c	1592.73 ± 0.06c
Na/K	0.12	0.15	0.14	0.14	0.14	0.16

In addition to macroelements, trace elements such as iron (Fe), zinc (Zn), copper (Cu), chromium (Cr), manganese (Mn), and selenium were present at relatively high concentrations (Table III). Iron (Fe) and Manganese (Mn) are the most abundant trace elements in the broths, with concentrations ranging respectively from 14.52 mg/100 g (B1) to 51.69 mg/100 g (B6) and from 4.01 mg/100 g (B1) to 14.49 mg/100 g (B6). Concentrations of minerals such as Zinc (Zn), Copper (Cu) and Selenium (Se) range from 6.33 (B6) to 8.61 (B3), from 2.21 (B6) to 4.07 (B3), from 2.34 (B2) to 3.14 (B6) and from 0.11 (B3 and B6) to 0.16 (B4), respectively.

Table III. Trace Element Composition of Seed-Based Broths From Ricinodendron heudelotii and Parkia biglobosa (mg/100g)

Broths	B1	B2	B3	B4	B5	B6
Cr	0.873 ± 0.006ab	0.777 ± 0.006a	1.613 ± 0.021c	0.87 ± 0.04ab	0.78 ± 0.017a	0.973 ± 0.005d
Mn	4.01 ± 0.02a	4.37 ± 0.06a	5.74 ± 0.06b	12.44 ± 0.27c	13.83 ± 0.06d	14.49 ± 0.06d
Fe	14.52 ± 0.442a	15.25 ± 0.03a	16.85 ± 0.0b	46.10 ± 0.01c	45.36 ± 0.05c	51.69 ± 0.07d
Cu	3.07 ± 0.0a	3.45 ± 0.0a	4.07 ± 0.03a	2.54 ± 0.01b	2.60 ± 0.07b	2.21 ± 0.03c
Zn	6.64 ± 0.04ab	7.41 ± 0.02a	8.61 ± 0.10a	6.69 ± 0.02b	6.66 ± 0.07b	6.33 ± 0.0c
Se	0.12 ± 0a	0.12 ± 0a	0.11 ± 0a	0.16 ± 0.0b	0.12 ± 0.0a	0.11 ± 0.0a

Discussion

The results revealed marked similarities and divergences between broths based on Ricinodendron heudelotii (B1–B3) and those based on Parkia biglobosa (B4–B6). Despite the similarity in pH values, titratable acidity was significantly higher in R. heudoletii broths than in R. heudelotii broths. This difference could be explained by the natural presence of organic acids such as ascorbic acid in P. biglobosa seeds [17], [18]. Furthermore, the results showed independence between the pH and titratable acidity values. This could be explained by the fact that some acids are weakly dissociated [19].

The moisture content of R. heudoletii and Parkia biglobosa broths was relatively low. These values were lower than those reported by Fatoumata et al. [18], which ranged from 14 g/100 to 26 g/100 FW, but lower than those reported by Kabré et al. [20]. This difference can be explained by the different drying methods used and the different inputs used in the composition of the broths. These low moisture contents could be advantageous for the conservation of the broths.

The broths in the present study were characterized by their high protein content, estimated at approximately. These levels were higher than those of glutamate broth (36.96%), which is an industrial broth with the highest protein content [21]. Broths based on spontaneous food plants such as Parkia biglobosa and Ricinodendron heudelotii are, therefore, far higher in protein content than commercial bouillon cubes [22]. These protein levels could be due to the composition of the raw materials used, namely the Akpi and Néré seeds. The average protein content of Akpi and Néré seeds is 34 g/100 g and 48 g/100 g, respectively [23], [24]. Thus, Akpi and Néré-based broths can supplement protein-poor diets in humans [25]. Furthermore, the similarly high values highlight the potential of both ingredients as sources of protein, corroborating the studies by Kinge et al. [23] on Ricinodendron heudelotii as a plant-based alternative rich in protein.

Dietary fiber levels in all broths varied from B4 to B5. The values observed are close to those found by Fatima and Al-Subhi [26] in mushroom-based broths (38.1 g/100 g) and vegetable-based broths (30.7 g/100 g). Fiber aids digestion by increasing gastrointestinal function, preventing constipation, and thus reducing the incidence of metabolic diseases, such as diabetes mellitus and hypercholesterolemia [27], [28].

The broths in this study had relatively low lipid and carbohydrate content. However, lipid levels are high compared to those of commercial brand seasoning broths and vegetable-based broths, which are generally low in fat [11]–[26]. Lipids are important biomolecules that function in the human body.

All the broths formulated in the present study showed high energy values, which were higher than those reported by Bamba et al. [6], who developed a powdered broth based on néré (Parkia biglobosa). Soumbala-based broths were more energetic than Akpi-based broths. The caloric difference from 289.93 Kcal/100 g to 440.65 Kcal/100 g is mainly attributable to lipids, a key factor for formulations aimed at populations with high energy requirements.

Analyses showed that the sodium levels of the broths in the present study did not exceed the recommended daily allowance [21]. In addition, all broths, particularly those based on Akpi, are exceptionally rich in potassium (up to 1530 mg/100 g), which is crucial for the regulation of arterial hypertension [29]. Consequently, the Na/K ratio is well below the recommended limit (<0.5) for preventing hypertension, unlike industrial broths often overloaded with NaCl [30]. Indeed, excess sodium is recognized as a factor that aggravates hypertension, stroke, and other cardiovascular pathologies [31]. Other macronutrients such as magnesium, phosphorus, and calcium are also present in appreciable quantities.

Analyses have also revealed the presence of trace elements such as iron, manganese, zinc, copper, chromium, and selenium, all of which are important for humans [32], [33]. The iron and zinc levels in our broths were higher than those determined by Bamba et al [6] for a broth made from néré (Parkia biglobosa). Iron plays a crucial role in hemoglobin formation and the prevention of anemia. Broths based on Parkia biglobosa (B4–B6) show higher concentrations, which could be explained by the intrinsic mineral composition of P. biglobosa seeds [24]. Manganese is essential for the metabolism of carbohydrates, amino acids, and cholesterol, as well as for bone formation. The significant presence of Manganese (Mn) in these broths, particularly in B6 broth, could help to cover the recommended daily intake.

Conclusion

This study showed that broths made from spontaneous food plants such as Akpi seeds (Ricinodendron heudelotii) and Soumbala seeds (Parkia biglobosa) present a good nutritional profile characterized by proteins and minerals such as calcium, potassium, and iron. This study highlights the need to valorize these neglected local species, particularly in food supply policies, to contribute to food security in Côte d’Ivoire. Their valorization could be an alternative to the diet of people suffering from diseases, such as diabetes and hypertension. Therefore, it would be interesting to study the sensory qualities of these broths to ensure their appropriateness.

Conflict of Interest

The authors declare that they have no conflicts of interest.