Abstract

Malnutrition remains a public health issue in several countries around the world. The objective of this study was to formulate a porridge flour from locally available ingredients to promote nutritional recovery in malnourished children and elderly people. After determining an appropriate formula, the recovery flour was produced and its physicochemical, nutritional, microbiological, and organoleptic parameters were analyzed. It should be noted that MANIBA flour (corn-cowpea-baobab) was produced in 5 hours and 20 minutes from a formulation composed of 76.3% corn, 8.5% cowpea, 8.5% baobab pulp, and 6.8% sugar, with a production yield of 84%. Physicochemical and nutritional analyses revealed that 100 g of flour contains calcium (95.08 ± 0.13 mg), magnesium (204.05 ± 0.45 mg), iron (0.15 ± 0.00 mg), and zinc (0.11 ± 0.01 mg). In terms of nutritional substances, it contains protein (10.08 ± 0.21%), lipids (4.27 ± 0.24%), carbohydrates (70.27 ± 0.52%) and has an energy value of 648.76 ± 1.93 kcal/100 g. Microbiologically, MANIBA flour complies with the standards of the Codex Alimentarius Commission. After sensory evaluation, MANIBA flour and its porridge were generally more appreciated and better accepted by consumers than other flours of the same category available on the Beninese market. These characteristics of MANIBA flour show that it can be validly included in the nutritional recovery diet of target populations.

1. Introduction

In underdeveloped countries, a large number of children do not receive adequate nutrition during early childhood ¹. According to UNICEF statistics, malnutrition or emaciation is the leading cause of mortality and morbidity. It accounts for 45% of deaths among children under the age of 5 each year ². The elderly are not spared from the harmful effects of malnutrition. As their bodies become more fragile with age, a specific diet should accompany the stability of their health. Among other solutions, the World Health Organization (WHO) recommends exclusive breastfeeding of newborns until the age of six months as an excellent way to combat infant malnutrition. After six months, liquid foods such as infant cereal porridge, fruit juices, and purées are recommended ³. During weaning, a sufficiently varied diet (solid, semi-solid, and soft foods from a variety of whole foods) should be introduced at frequent meals to meet the child's nutritional needs as a supplement and gradual replacement for breastfeeding. In Benin, scientists have proposed food formulations to address the problem of malnutrition. Examples include the formulation of infant cereal based on fonio and local ingredients by Syka et al., ⁴; the formulation and commercial production of infant flours by state structures such as the Beninese Food Technology Unit (UBETA) and private structures such as the Oasis Children's Center. These local solutions do not seem to meet the expectations of international institutions in terms of eradicating malnutrition in the country ⁵. The choice of foods for nutritional recovery is a real problem due to the lack of variability in the agri-food production on offer. People are resorting to food preparations and products of dubious origin, which is leading to a deterioration in their health.

However, Benin's agricultural sectors offer a diversity of crops that present real opportunities for investors, particularly in the agri-food industry. Benin produces up to 132,500 tons of cowpeas and 1,580,750 tons of corn per year ⁶. Corn is a cereal that generally provides the energy necessary for the body to function thanks to its high carbohydrate content. Cowpeas are a readily available legume, rich in the proteins needed for the growth and renewal of our tissue cells (cell construction and repair). Cowpeas also contain certain micronutrients (iron, magnesium, and vitamins) ⁷. Despite these agricultural achievements, malnutrition still persists among different segments of the Beninese population. According to the United Nations ⁸, the results of the Multiple Indicator Cluster Survey (MICS) revealed that in 2014, more than one in three children in Benin suffered from stunted growth, known as chronic malnutrition. Although this trend appears to have improved slightly over the years, the latest report from INSTaD (National Institute of Statistics and Demography) states that from 2021 to 2022, more than 45% of infant mortality is due to malnutrition in various forms ⁸. Children living in rural areas are more affected by stunted growth (35%) than those living in urban areas (25%).

Improving the nutrition of infants, young children, and the elderly is clearly a priority. To achieve this, particular attention must be paid to the nutrition of these vulnerable segments of society through the development of varied and balanced foods. The present study set out to formulate a porridge flour called “MANIBA” from local ingredients (corn, cowpea, and baobab) for the nutritional recovery of children and the elderly.

Specifically, the aim was to (i) formulate MANBA nutritional recovery flour; (ii) evaluate the technological performance of MANIBA flour production; and (iii) characterize this flour in terms of its physicochemical, microbiological, and organoleptic properties.

2. Materials and Methods

• Plant material and ingredients (Figure 1): These included white corn and red cowpeas, supplied by the food crop storage services of the International Institute of Tropical Agriculture (IITA-Benin), pulp collected from baobab fruits purchased from field collectors, and sugar purchased from supermarkets.

• The production equipment included: basins, sieves, pots, a mill, buckets, water, dishcloths, a ladle, a trash can, a dryer, packaging, and a scale. These items were available at the Food Science and Technology Laboratory (LaSTA) of the Faculty of Agricultural Sciences at the University of Abomey-Calavi (FSA-UAC).

• The laboratory equipment consisted of standard equipment for physical, chemical, microbiological, and sensory analysis.

n Theoretical formulation of MANIBA flour

Formulas were developed to achieve the best quality. For this work, the 2019 version of the West African Food Composition Table, FAO ⁹ was used to determine the nutritional composition of the ingredients used and to theoretically estimate their nutrient content, Solver software was used to create different combinations of raw materials, taking into account the following matrices: the price of each raw material; the macronutrient composition of the raw materials (protein, fat, and energy); the recommended macronutrient content per 100g of infant flour according to the Codex Alimentarius (Table 1).

n Theoretical composition of the formulated flour

Table 2 shows the theoretical nutritional value of the flour obtained based on the nutrient composition of the ingredients used in the formulation.

n Application of infant flour formulas

Table 3 shows the proportions of each raw material used in the composition of the formulated infant flour.

n Unit operations and production yield of formulated infant flour

Depending on the raw material concerned, various unit operations were carried out in chronological order, culminating in grinding. The production process diagram (Figure 2) summarizes the operations performed to produce the formulated flour. During production, critical points such as the selection and sorting of raw materials and ingredients, temperature and time control during heat treatments, and the selection of sterile packaging were necessary to prevent contamination of the flour at the end of production. The various unit operations resulted in final quantities of ingredients that were lower than the initial quantities. The production yield is determined by the following formula (1):

(1)

Production was carried out three times, and each of the flours obtained was used as a sample for microbiological, physicochemical, nutritional, and organoleptic analyses. Each sample was analyzed three times.

The protein content is determined using the Kjeldahl method, the reference method ¹¹. The lipid, carbohydrate, and ash content of the formulated flour was determined using the appropriate methods described by AOAC-2000, ¹². To determine the fiber content of the infant flour produced, the chemical reagent treatment method was used according to the protocol described by Tchekessi, ¹³ for the determination of crude fiber. The energy value (EV) of the samples was calculated using Atwater's specific coefficients for protein, lipids, and carbohydrates. It was expressed in KJ/g, calculated and converted according to the following formula (2):

EB (KJ/g) = 23.65 × (% protein / 100) + 40 × (% lipid / 100) + 16.8 × (% carbohydrate / 100)(2)

EB = gross energy

The microelements (iron, calcium, magnesium, zinc) were measured by atomic absorption spectrophotometry. The samples submitted for analysis were reduced to powder. The powder was incinerated in an oven at 550°C for 24 hours. The resulting ash was dissolved in water, in 2 ml of HCL (6N), which was evaporated on a hot plate at 125°C. The more or less viscous residue obtained was dissolved again in a flask containing 100 ml of a 0.1 mol/l molar concentration HNO3 solution. The solution obtained was used to measure the metals by atomic absorption spectrophotometry. The dry matter (DM) content of the various samples of infant formula was determined using the AOAC method ¹².

The pH and titratable acidity were determined using the AACC 14.022 method adopted by Tchekessi, ¹³.

Four samples of infant formula were analyzed under the conditions described in Table 4. The bacteria counted were total mesophilic aerobic bacteria (TMAB) according to ISO 4833, ¹⁴, in order to assess the level of contamination of the product by microorganisms. Yeasts and molds were counted according to standard NF V 08-059: 2002, adopted by Nonviho et al., ¹⁵ to assess the effectiveness of heat treatments that may or may not have been applied to raw materials and intermediate products during production. Enterobacteria were tested in accordance with standard NF V 08-059: 2002 in order to determine whether hygiene conditions had been respected during the production of infant formula.

The sensory evaluation was carried out by a panel of 40 tasters selected at random using hedonic testing methods. This allowed the panel members to assess the organoleptic quality of the porridges prepared from infant flours formulated according to the following parameters: taste, texture, color, smell, aroma, and consistency. They rated the porridges on a seven-point scale ranging from “extremely inferior” to “extremely superior.” They also assigned an overall preference score from 1 to 9 to the porridges prepared from MANIBA flour and an authorized reference flour available on the market. Composed of a diverse group of 40 randomly selected individuals of both sexes. Each panel taster was presented with two identical bowls, labeled MANIBA and control. Each bowl contained an equal amount of porridge corresponding to the label. Participants were asked to rate each porridge using the following scale: 1 = extremely inferior, 2 = very inferior, 3 = moderately inferior, 4 = slightly inferior, 5 = identical to the reference sample, 6 = slightly better, 7 = moderately better, 8 = better, and 9 = extremely better. At the same time, based on each of the criteria mentioned above, the taster chose the best porridge according to their preferences, without assigning a score.

The Solver function in Excel was used to determine the quantity of ingredients used. Microsoft Excel 2013 was used to calculate the results of the laboratory analyses of the physical and chemical parameters. Color, taste, smell, consistency, and aroma were scored according to the following ratings. The means and standard deviations were calculated using Excel to determine whether there were significant differences in the average degree of appreciation between the samples. The level of significance was set at 5% (p<0.05) using SAS Version 9.2 software and the Student Newman-Keuls test for comparing means.

3. Results and Discussion

Figure 2 shows the physical appearance of MANIBA flour, which was formulated, produced, and packaged in 200 g bags. For 5 kg of ingredients (details of which are given in Table 5), 4.2 kg of MANIBA recovery flour was produced, representing a yield of 84%. The production cycle for flour based on this cereal was approximately 6 hours.

After formulation, it was found that the production of MANIBA flour required unit operations. All of these unit operations have a production cycle of approximately six (6) hours. This cycle is short and could allow for rapid intervention in emergencies to correct acute malnutrition, especially in children. The production yield obtained (84%) is relatively low compared to the 90% yield obtained by Sika et al., ⁴, who produced infant flour formulated from fonio, corn, owpea, supplemented with cow's milk, baobab pulp, and other local ingredients. This difference could be explained by the fact that during sorting, a significant amount of waste, such as damaged seeds that constitute antinutritional factors, is discarded and has not been compensated for by the addition of baobab pulp alone.

Table 6 shows the average macronutrient and trace element content of MANIBA flour. Based on the analysis of this table, it appears that the flour is sufficiently rich in macronutrients (proteins, lipids, and calories) and minerals (calcium, magnesium, iron, and zinc) to cover the recommended nutritional intake for an individual.

The physicochemical characteristics of the flours produced revealed a high dry matter content (90.49 ± 0.26%). For children, this type of porridge is a source of energy that can promote weight gain. Indeed, the higher the dry matter content, the thicker and more energy-rich the porridge. The incorporation of cowpea and corn into the formula resulted in an energy density of 648.76 ± 1.93 kcal/100 g. These results are consistent with those of Elenga et al., ¹⁶, who showed that incorporating malt and calcium carbonate into fermented corn and peanuts made it possible to prepare porridges with a recommended consistency of 120 mm/30 s for a dry matter content of 20%. According to these authors, this porridge, intended for infants and young children, has an energy value of 400 kcal/100 g, as recommended by the CAC standard ⁷. Furthermore, the consumption of foods that are sources of vegetable protein, such as cowpeas and certain legumes, should be encouraged as they are readily available and inexpensive. In addition, the fortification of cereals with cowpeas has increased the protein content of MANIBA flour to 10.08 ± 0.21/100g. These results are consistent with those of Solomon ¹⁷ and Onilude ¹⁸, who found in their studies that the protein content of combined cereals and legumes is better than that produced from cereals alone. The lipid content of MANIBA infant formula is 4.27 ± 0.24/100 g. This content is below the Codex Alimentarius standard, which is 10 to 25 g/100 g. This could be explained not only by the fact that the ingredients used are low in lipids but also by the absence of a lipid source such as peanuts in the formula. These results are consistent with those obtained by Kayode et al. ¹⁸, who showed that porridge made from sorghum, soybeans, and fretin had the highest lipid content (5.4%) compared to porridge made from sorghum, cowpeas, and peanuts (0.85%). With regard to minerals and trace elements, the calcium and iron content of MANIBA flour is below the Codex Alimentarius standard. This could be related to the composition of the ingredients and raw materials used. Indeed, the source of minerals used was baobab pulp. The mineral content of this ingredient, as determined by Aïda ²⁰, (2 mg of iron, 1 mg of magnesium, 2,310 mg of calcium, and 10 mg of zinc in 100 g of pulp), is still too low to fully meet the recommended daily intake. The slight deficiencies in Ca, Fe, and Zn in MANIBA flour could be compensated for by other carefully selected foods to accompany the porridge prepared from this flour.

Table 7 shows the microbiological characteristics of MANIBA flour formulations. Analysis of this table reveals that MANIBA flour is of satisfactory microbiological quality, as the contamination levels of mesophilic aerobic bacteria (MAB), enterobacteria at 37ºC, yeasts, and molds remain below the regulatory limit set by the Codex Alimentarius Commission.

Microbiological analyses show that there is no significant contamination of MANIBA flour compared to CAC ¹⁰ standards, considering the microbiological parameters GAMT, enterobacteria, yeasts, and molds. This shows that the flour was produced in accordance with good hygiene and manufacturing practices.

Figure 4 and Figure 5 show the sensory profile of the MANIBA recovery flour formulated and produced (Figure 4), as well as that of its porridge (Figure 5). These profiles are obtained by comparing the average scores assigned to each organoleptic parameter at the 5% threshold. Analysis of the sensory evaluation results revealed that MANIBA flour was generally better accepted by the sensory evaluation panel than the control flour purchased on the market. In particular, all sensory parameters, namely color, appearance, and odor, were significantly more appreciated for MANIBA flour than for the control flour purchased on the market, at the 5% threshold (p˂0.05). However, consumers reported that the flours (MANIBA and control) had the same texture (Figure 4).

Furthermore, according to the observations made by the tasters, the porridge made with MANIBA flour was significantly more appreciated at the 5% threshold (p˂0.05) due to its sensory characteristics (color, texture, appearance, smell, and taste) and was more accepted than the porridge made with the control flour at the 5% threshold (Figure 5).

The results of the sensory analysis revealed that porridge made from MANIBA flour is of better organoleptic quality and has significantly higher acceptance than the control flour purchased from the market. MANIBA flour can therefore be included in the diets of both children and the elderly.

4. Conclusion

At the end of this study, it should be noted that “MANIBA” porridge flour is formulated and produced from corn, cowpea, and baobab pulp with a yield of 84%.This flour is of good nutritional, physicochemical, and microbiological quality. Porridge made from MANIBA flour is highly appreciated by consumers and can be included in the nutritional recovery diet of children and the elderly.

ACKNOWLEDGEMENTS

The authors would like to thank the Multidisciplinary Research Laboratory for Technical Education (LARPET) of the National University of Science, Technology, Engineering, and Mathematics (UNSTIM) for its support in carrying out this research work.

Conflict of Interest

This study does not present any conflicts of interest

References