Nutritive bambara groundnut powdered drink mix: characterization and in-vivo assessment of the cholesterol-lowering effect

Abstract

Drought has become more frequent due to climate change and its effects on the agricultural sector can be devastating. This increases the need for drought tolerant crops such as the Bambara groundnut (BGN) to be farmed in Malaysia. The development of BGN to a product suitable for consumers in this region has not been studied. Therefore, this research aimed to determine consumer acceptability of a nutritive BGN powdered drink mix using the Just-About-Right (JAR) method. BGN flour was produced by mixing soy powder with 0% BGN powder (0B100S), 10% BGN powder (10B90S), 20% BGN powder (20B80S) and 30% BGN powder (30B70S), respectively. The physicochemical properties of the powdered drink mix and its microbiological changes upon storage for six months were then determined. In addition, in-vivo assessment of the cholesterol-lowering effect of this product was conducted. Sample 10B90S was the most preferred sample among the sensory panellists (overall acceptability = 72%). Sample 10B90S remained stable after six months of ambient storage. Rats fed with sample 30B70S showed the most improvement in blood cholesterol levels. In conclusion, nutritive BGN powdered drink mix exhibited good physicochemical properties and could be useful for food applications.

Introduction

Bambara groundnut (Vigna subterranean) is one of the crops in Africa but it was neglected and underutilized due to the difficulty in cooking and processing. This legume possesses properties similar to the ordinary peanut as they have similar pods that are formed and ripen beneath the ground (Kendabie et al. 2012). Its high nutritional values could have a specific potential to improve nutrition among humans, especially in rural areas. The Bambara groundnut (BGN) is capable of fixing atmospheric nitrogen to the earth to benefit its related ecosystem (Gbenyi et al. 2016). Besides, BGN can resist various plant related pests and diseases and can thrive in poor soils (Eltayeb et al. 2011).

BGN is grown primarily for human consumption and can be consumed in various ways, both unripe and fully ripen. Unripe BGN can be consumed raw, grilled, or parboiled. Surprisingly, unripe BGN is considered more palatable compared to the hard, ripened seeds. Unripe BGN seeds are generally consumed as a snack by roasting the seeds, and they are also cooked as a stiff porridge (Kendabie et al. 2012). Ripened seeds are usually ground into powder and eaten as congee. Despite the advanced uses of BGN, it remains underutilized for several reasons. For example, BGN is traditionally cultivated by women and consumed by the poor in rural areas. It is also a less popular legume due to its difficulty for cooking.

In the past few years, there has been an increasing market for powdered drink mix, which instantly dissolves in water. Instant powdered drinks are increasing in popularity among consumers these days due to its convenience, high nutrition and good sensory profile (Kendabie et al. 2012). Milk, coffee, malted beverages, and health supplements are examples of popular foodstuffs in the market that match our pace of life. This research is aimed to produce a BGN powdered drink mix and to look for the best formulation for consumers.

BGN is rich in essential nutrients (Ncube et al. 2007). This potentially helps prevent malnutrition caused by inadequate diets (McGown 2006). It helps reduce the effects of anaemia because it contains iron and other essential nutrients that can increase human blood levels (McGown 2006). The presence of antioxidants in BGN protects the body from harmful food chemicals and, therefore, reduces the risk of cancer and other health problems. Minerals (such as calcium) contained in BGN protects the body from arthritis, osteoporosis, and other related bone diseases (Ncube et al. 2007).

Crops For the Future (CFF) is a research company founded by the government of Malaysia and the University of Nottingham, which focuses on diversifying future agriculture and the improvement of underutilized crops (Gregory et al. 2019). BGN was identified as one exemplar crop to be planted in Malaysia but the development of novel foods using BGN that are suitable for consumers in this region is not well documented. In view of this, one of the main objectives of this research was to determine consumer acceptability of BGN powdered drink mix using the Just-About-Right (JAR) scale. Physicochemical properties such as pH, color measurement, proximate analysis, and functional properties of the newly developed BGN powdered drink mix were determined. The microbial changes of samples upon six months of storage and its’ in-vivo assessment of the cholesterol-lowering effect were also determined.

Materials and methods

Materials

Bambara groundnuts (BGN)

Dry Bambara groundnut (BGN) was obtained from Crop For the Future in Semenyih, Malaysia. Upon arrival at the food science laboratory at UCSI University, sorting was carried out to remove unwanted foreign substances. The cleaned BGN was then kept in a freezer at − 4 °C.

Animals

After obtaining the animal ethical approval from the UKM animal ethics committee (code: UCSI/2017/CHOON HUI/24-MAY/849-AUG.-2017-AUG.-2018)., thirty female Sprague Dawley rats were obtained from Sinar Scientific Sdn Bhd, Serdang Malaysia.

Preparation of bambara groundnut milk

BGN was soaked in cold tap water for 8 h, followed by boiling in hot water for 30 min. Then, the hull's extra skin was removed and and the seeds blended with warm water at a ratio of 1:3 (BGN: Water) for 15 min until a homogenized paste was produced. The slurry was then homogenized at a speed of 20,000 rpm for 15 min. The dough was then dried in an oven at 40 °C for 12 h. The hardened BGN sheets were blended again using a food processor (KENWOOD FDM302SS, USA).

Meanwhile, using the same method, fresh soybean purchased from a local market was used to produce soy powder. The BGN and soy powder produced were kept in an air-tight plastic bag. Next, the two powders were mixed into different formulations of 0% BGN, 10% BGN, 20% BGN, and 30% BGN.

Sensory evaluation

One hundred panellists were recruited to participate in the Just-About-Right (JAR) test. Four different formulations with different proportions of BGN were presented to the panellists. Each panellist was given a set of consent and sensory evaluation forms that consisted of JAR scales. Additionally, panellists were also provided with a glass of water as they were required to rinse their mouths before trying each sample of different formulations.

Physicochemical analysis

Physicochemical analysis was carried out on the nutritive BGN powdered drink mix to determine its properties and, consequently, safety measures to prevent or slow down the onset of microbial spoilage were created.

pH

A benchtop pH meter was used to determine the pH of the BGN powdered drink mix with three replications.

Water activity (Aw)

Water activity of the nutritive BGN powdered drink mix was measured using a Aw analyzer (Aqua Lab, United States). Five grams (5 g) of the sample was transferred into a sample plastic cup and placed into the Aw meter; then, the reading was obtained from the meter. The analysis was carried out in a triplicate, and the readings were then averaged.

Color measurement

The color of the nutritive BGN powdered drink mix was measured using a Hunter colorimeter (Hunter Lab, USA). Three grams of the sample was placed in a sample cup for reflectance measurement for lightness (L*), redness (a*), and yellowness (b*). Before the analysis, the instrument was calibrated using a black tile (L*: 55.49, a*:527.08, b*:54.66), followed by a white tile (L*: 593.41, a*:521.18, b*:50.75). The measurement of each sample was performed in triplicate, and the samples were placed in different positions.

Bulk density (BD)

For this analysis, bulk density was determined by the method described by Maninder et al. (2007). Sample powder was filled into a cylinder and the cylinder was tapped on a bench several times until the sample reached 10 ml mark. BD was calculated as weight of sample per unit volume of sample (g/ml).

Water and oil absorption capacity

One gram of product sample was weighed, mixed, and swirl with 10 ml of distilled water thoroughly for 30 s. It was then put into a graduated centrifuge tube and allowed to stand for 30 min at room temperature (28 °C). Next, it was centrifuged at 5000 g for 30 min. After centrifugation, solute and supernatant separation occurred. The volume of supernatant was recorded (Lario et al. 2004).

Gelation concentration

A 2%—20% (w/v) of sample suspension was prepared with 5 ml of distilled water. The sample suspensions were heated in a water bath (100 °C) for an hour and then cooled under running tap water. The test tubes were allowed to stand at 4 °C for further cooling for another 2 h. The gelatinization status was observed by inverting the test tube (Lario et al. 2004).

Proximate analysis

The macro-nutrient of the nutritive BGN powdered drink mix was determined using proximate analysis according to AOAC methods, which included moisture (AOAC method 930.15), protein (AOAC method 955.04), fat (AOAC method 920.39), and ash (AOAC method 923.03) contents. Carbohydrate was quantified by calculating the difference between 100 and the total sum of moisture, protein, fat, and ash contents.

Storage stability test

The nutritive BGN powdered drink mix was kept in a plastic bag and packed individually for storage. Samples were stored in a cool, dry and dark place. Microbial enumeration was carried out at a weekly interval for three months. Potato dextrose agar was used for the fungal screening and isolation test.

In-vivo study on cholesterol-lowering effect

Experimental design

In this study, thirty mature female Sprague Dawley rats (body weight between 250–300 gm) were housed in groups of three in cages at the animal holdings unit in UCSI University, Kuala Lumpur, Malaysia. They were kept under standard environmental conditions (temperature: 22 + 1 °C; humidity (75 + 5)% and light/dark schedule 12/12 h). The rats were allowed to acclimatize for two weeks and fed with a regular diet before further treatment. The weight of each rat was recorded and their physical behaviors were observed. The rats were separated into five groups (A-E) where animals in group A was the non-treatment control group with regular feed while animals in group B to group E were fed with a high cholesterol diet (HD). After two weeks of induction, animals in Group C, D, and E were supplied with 10% of commercial drug (simvastatin) in controlling blood cholesterol levels, pure BGN powder, and the BGN powdered mix, respectively. The weight change of the animals was recorded daily and the treatment period was eight weeks. Meanwhile, feces were collected from the cages on a weekly basis and stored in transparent plastic bags prior to analysis. All feces samples were dried in an oven until a constant weight was obtained. At the end of the experiment period, the animals were sacrificed using a ketamine/xylazine combination of drugs. The duration of anesthetic ether inhalation was about 5–8 min. The livers of rats were taken out for observation and the weights recorded. All blood samples and fecal outputs were collected and delivered to a private laboratory in Kuala Lumpur for biochemical analysis.

Statistical analysis

All analyses were carried out in triplicate, and results were reported in mean ± standard deviation values. The data collected were subjected to the analysis of variance (ANOVA) using the SPSS statistical software (version 20). The split of the mean values was carried out using the Duncan multiple range test, at 5% significance level. The JAR scale results were analyzed using the XL-stat penalty test.

Results and discussion

Sensory evaluation

Figure 1 shows the percentage for the JAR level of nutritive BGN powdered drink mix samples. The scores of Sample 10B90S (10% BGN incorporated with 90% soy powder) for appearance, aroma, flavor, viscosity, grittiness and overall acceptability is 76%, 54%, 88%, 66%, 72%, 72%, respectively. This is the best profile among all formulations because most of the sensory attributes fall in the just-about-right range (> 70%). Meanwhile, the scores of Sample 20B80S (20% BGN incorporated with 80% soy powder) for appearance, aroma, flavor, viscosity, grittiness and overall acceptability were 64%, 48%, 50%, 60%, 50% and 56%, respectively. As for Sample 30B70S (30% of BGN and 70% of soy powder), it received the least percentage of overall acceptability. The results showed that the aroma, flavor, and grittiness of Sample 30B70S were ‘too much’. This was because of the higher proportion of BGN incorporated with soy powder, which resulted in a darker milk liquid and a more intense beany flavor.

Fig. 1.

Percentage of JAR level for (a) 0B100S (Control: 0% BGN, 100% Soy); (b) 10B90S (10% BGN, 90% Soy); (c) 20B90S (20% BGN, 80% Soy); (d) 30B70S (30% BGN, 70% Soy)

Research from Nnam (1994) showed that the preference of consumers on the texture of milk was affected by its color. Nnam (1994) mentioned that the nutritional profile of BGN milk was promising and favorable with other vegetable milk, and panelists preferred its organoleptic properties. Also, vegetable milk had better dietary benefits due to its high mineral content. Obizoba and Egbuna (1992) mentioned that BGN is always associated with beany taste and odor. Hence the BGN must be heat treated before further processing.

Physicochemical analysis

Water activity (Aw) and colorimetric test

Table 1 shows that the Aw of Sample 0B100S was significantly (p < 0.05) the highest (0.37), while the 30B70S had the lowest value (0.26). The Aw of a food sample can be defined as the strength of water content that is obtainable for the growth of microorganisms (Fontana and Campbell 2004). Lower Aw has a directly proportional relationship with the microbial activities and the shelf-life stability of the food product (Fontana and Campbell 2004). Hence, the low Aw of every formulation in this study makes it a potentially stable milk variant.

Table 1.

Mean value of Aw and colour profile of nutritive BGN powdered drink mix

Formulation	Aw	Colorimetric
		L*	a*	b*
0B100S	0.37 ± 0.01a	87.94 ± 1.69a	1.17 ± 0.20a	22.02 ± 0.19a
10B90S	0.33 ± 0.09b	85.79 ± 0.01a	1.24 ± 0.11a	20.39 ± 0.02b
20B80S	0.28 ± 0.03c	84.39 ± 0.05ab	1.50 ± 0.17b	19.60 ± 0.04c
30B70S	0.26 ± 0.03c	83.51 ± 0.03b	1.67 ± 0.06c	18.91 ± 0.02c

0B100S—0% BGN; 10B90S—10% BGN; 20B80S—20% BGN; and 30B70S—30% BGN

^abcMean values with the different superscript letter within same column are significantly different (p < 0.05)

From Table 1, the mean value of lightness (L*) of Sample 0B100S was significantly (p < 0.05) the highest (87.94) while Sample 30B70S was the lowest (83.51), which indicates that the higher the content of BGN powder in the formulation, the darker the color of the BGN drink mix. The redness (a*) of all formulations showed significant (p < 0.05) differences where Sample 30B70S had the highest hue angles (1.67), and Sample 0B100S had the lowest value (1.17). On the other hand, the yellowness (b*) of Sample 0B100S was the highest (22.02) and decreased significantly (p < 0.05) when the proportion of BGN decreased. In short, the incorporation of BGN into soy powder could result in a darker color of the nutritive powdered mix.

Functional properties

Bulk density (BD), which is the heaviness or dry weight of the solid powder per unit volume of the total solid powder, is highest in 30B70S (0.51 g/cm³) and lowest in 0B100S (0.46 g/cm³), as shown in Table 2a. This range was higher than results from Kudre et al. (2014), who found that they ranged between 0.33–0.43 g/cm³ whereas the results obtained by Adebowale et al. (2011) was between 0.58 and 0.73 g/ml. Research from Adebowale et al. (2011) observed that the solubility of BGN flour was highly dependent on pH levels and would decrease as the pH increase until the isoelectric point was achieved. The same research also showed that the solubility profile of a protein isolate is necessary for the food industry as the processing process might cause the denaturation of protein.

Table 2.

Functional properties of nutritive BGN powdered drink mix

Formulation	BD (g/cm3)	WAC (g/cm3)	OAC (g/cm3)	GC (w/v)
0B100S	0.46 ± 0.06a	1.16 ± 0.08a	2.06 ± 0.08a	3.08 ± 0.10a
10B90S	0.48 ± 0.06b	1.24 ± 0.09a	1.95 ± 0.09a	4.11 ± 0.15b
20B80S	0.47 ± 0.01c	1.87 ± 0.11b	1.82 ± 0.07b	5.06 ± 0.09c
30B70S	0.51 ± 0.01d	2.28 ± 0.21c	1.87 ± 0.20b	5.07 ± 0.08d

0B100S—0% BGN; 10B90S—10% BGN; 20B80S—20% BGN; and 30B70S—30% BGN

BD bulk density, WAC water absorption capacity, OAC oil absorption capacity, GC gelation concentration

^abcMean values with the different superscript letter within same column are significantly different (p < 0.05)

Sample 10B90S had a BD value of 0.48 g/ml, which was 4.16% higher than pure soy powder and also higher than that of conophor flour (0.41 g/ml) as reported by Adeleke et al. (2018). This indicates that soy powder incorporated with BGN powder has a higher mineral content and is able to form thicker beverages when mixing with hot water due to the low dispersion rate of particles (Akinjayeju and Enude 2002). BD may affect how a product can easily be handled or packaged (Onwuka and Abasiekong 2006).

Water absorption capacity (WAC) of the flour is essential to express the volume of water needed to maintain a standard viscosity. Table 2 shows the WAC in this study, which ranged between 1.17 and 2.28 g/cm³. The 30B70S had the highest WAC value (2.28 g/cm³), which is significantly (p < 0.05) different from the value of pure soy powder (0B100S), which was 1.17 g/cm³. High WAC was due to the high content of protein (polar amino acid) in hydrolysis. Hence, it had a higher affinity towards water molecules, while the low WAC flour was suitable for the formulation of more moderate protein, thinner beverage, or gruels (Onwuka and Abasiekong 2006). Sample 10B90S had a WAC of 1.25 g/cm³, which is similar to the WAC of pearl millet flour, which is 1.29 g/cm³ (Neelam et al. 2012). As the protein content had more swelling ability and active binding sides, the incorporation of BGN in soy powder could improve the consistency of powder mix.

Oil absorption capacity (OAC) was the highest in the pure soy sample (0B100S), which was 2.07 g/cm³ and lowest in sample 30B70S, which was 1.87 g/cm³ as shown in Table 2. Sample 10B90S had a moderate OAC reading, 1.95 g/cm3, which is 5.52% lower than pure soy powder. A result from Adeleke et al. (2018) showed that defatted protein concentrated would have higher OAC. The low level of OAC was due to inadequate hydrophobic protein that exposed the active binding site and hence had the least physical entrapment of oils.

Adeleke et al. (2018) mentioned that BGN is suitable for the production of beverage and gruels and is not ideal as an ingredient in the frozen meat industry. The rate of protein binding to fat is relatively low. Research from Awolu (2018) showed that pure wheat flour had the highest OAC, followed by cocoyam, and BGN had the lowest value, which was similar to the result of this research.

Gelation capacity (GC) is the ability of starch present in samples to absorb hot water that is added and resulting in swelling. It was desirable to have high gelation capacity in infant formulation (Kudre and Benjakul 2014) and is required to be lower in daily beverage products. The pure soy formulation 0B100S had the least gelation capacity at 3.08 w/v, while the highest reading was observed in sample 30B70S, which was 5.07 w/v. Sample 10B90S had 4.12 w/v GC, which was 24% higher than the pure soy formulation. Research from Kudre and Benjakul (2014) indicated that the process of BGN (sprouting, fermentation, or the blending ratios) had no significant affect (p > 0.05) on the GC.

Proximate analysis

From Table 3, the chemical composition of all formulations was significantly (p < 0.05) different. The moisture content of Sample 0B100S was the highest (5.43%), while Sample 20B80S showed the lowest moisture content (4.48%). These values were slightly lower compared to the values reported by Adebowale et al. (2011), which were 5.64% and 6.82% for white and brown BGN flour, respectively. This may be due to different processing conditions used in this study.

Table 3.

Proximate analysis of nutritive BGN powdered drink mix

Formulation	Mean value (%) ± Std Dev
	Moisture	Fat	Protein	Ash	Carbohydrate
0B100S	5.43 ± 0.10a	2.72 ± 0.08a	13.12 ± 0.03a	3.01 ± 0.26a	75.73 ± 0.41a
10B90S	4.89 ± 0.09a	2.15 ± 0.93b	13.12 ± 0.05b	1.98 ± 1.13b	77.86 ± 0.42b
20B80S	4.48 ± 0.09a	2.23 ± 0.05c	15.13 ± 0.05c	1.78 ± 0.36c	76.38 ± 0.49c
30B70S	5.22 ± 0.10b	3.02 ± 0.04d	15.15 ± 0.04d	1.52 ± 0.32c	75.09 ± 0.49c

0B100S—0% BGN; 10B90S—10% BGN; 20B80S—20% BGN; and 30B70S—30% BGN

^abcMean values with the different superscript letter within same column are significantly different (p < 0.05)

Fat contributes to the appearance, taste, durability and texture of food products (Abbas et al. 2010). The fat content of Sample 30B70S was the highest (3.02%) while Sample 10B90S contained the lowest fat content (2.15%). George and Awopetu (2017) reported that the crude fat (1.92%) of BGN milk powder was higher than soy milk powder. Meanwhile, Sirivongpaisal (2008) reported that the fat content of pure BGN flour was 16.60%.

Analysis of protein content in food products is critical for the investigation of functional properties, nutrition labeling, and the determination of biological activity (Chang and Zhang 2017). Sample 30B70S with the most BGN powder contained the highest protein content (15.15%), while Sample 0B100S contained the lowest in protein content (13.12%). George and Awopetu (2017) reported that the crude protein of BGN milk was 5.4%. On the other hand, the result obtained from this study was slightly lower compared to results obtained by Sirivongpaisal (2008) and Enwere and Hung (1996), where the BGN flour comprised of 15.48% of and 16.60% protein, respectively.

The examination of ash helps to measure the overall mineral content of food by assessing the residual inorganic traces after organic matter has been burned away. Results showed that the ash content of control samples was the highest (3.01%) while the lowest was found in Sample 30B70S (1.52%). The value obtained from this study was higher than those reported in Harris et al. (2017), which was only 0.36%. The carbohydrate content of Sample 10B90S was the highest (77.86%) while Sample 30B70S contained the lowest carbohydrate content (75.09%). Based on Alakali and Satimehin (2007), on dry basis, Bambara groundnut consists of 51–70% carbohydrate, 16–12% oil, 18.0–24.0% protein (with high lysine and meteomine content), 3.0–5.0% ash, 5.0–7.0% fat, and 5.0–12.0% fiber. However, the value obtained from Harris (2017) was relatively lower than this study, which was 11.46%. This might be due to the quality of the different varieties of bambara groundnut as well as the effect of different processing treatments used in the study (Nti 2009).

Storage stability test

There was no significant (p > 0.05) difference in the total plate count, yeast and mold counts among BGN samples during the 6-month storage period. Furthermore, the flowability of the powder was smooth, and no clumps were found at the end of storage. This could be due to the fact that the water activity of BGN powdered mix was low. Hence, it could be concluded that the BGN powdered mix is shelf-stable and can be stored at room temperature.

In-vivo study

Plasma lipid profile

Figure 2 shows the total cholesterol (TC) of animals in different groups. The animals in control group (ND) had the lowest TC value due to a normal diet without any treatment. The negative treatment group, which was fed with simvastatin, had the second lowest TC value. The result showed a significantly difference (p < 0.05) in the mean value of plasma cholesterol levels between the control group and all legume diet groups.

Fig. 2.

Total cholesterol (TC) on different rats group (ND Non-treatment group, Positive—without treatment, Negative—with commercial drug, BGN-rats treated with BGN powder, 10B90S—rats treated with 10% BGN and 90% Soy)

Research from Omogbai and Aghahowa (2017) showed a similar plasma profile of legume for marrowfat-pea and lentil. However, a study from Harris (2017) showed no significant differences in plasma lipid profile observed between the BGN diet-fed rat group. Hence, he concluded that BGN had no significant effect on maintaining a healthy lipid profile. On the other hand, Diedericks and Jideani (2015) mentioned that the total flavonoid, tannins, saponins, and dietary fiber act simultaneously to lower the blood cholesterol level. Diedericks and Jideani (2015) also stated that the flavonoid present in legume helps to lower blood cholesterol levels in-vivo. Chen and Nelson (2005) explained that the flavonoid effect was due to the inhibition of hydroxyl methyglytarycoenzyme, a reductase activity and consequently increased the residue of fecal bile acid.

Rat weight

From Table 4, the average weight of rats in each group showed significant differences (p < 0.05). The average weight of rats in group B (adverse treatment) increased dramatically as the procedure went and peaked to the highest value (222 g) during the fourth week. In contrast, the rats in group D that were fed with BGN powder showed the lowest average weight of rats (219 g) in week 4. The rats in group E that were treated with the nutritive BGN powdered mix (10S90B) had minimal weight gain during the four weeks of treatment compared to rats in group A (Normal Diet). The result showed that the treatment group with 10B90S and BGP were able to control rat’s weight despite the hypercholestemic diet. Studies from Chowdhury et al. (2018) showed that excess weight gain could increase cardiovascular diseases. Moreover, as the treated rats were being observed, no changes in feeding patterns were detected, and hence this could be concluded that the feeding of BGP had no effect on the appetite of rats.

Table 4.

Average of rats weight during treatment

Group	Week 0 (g)	Week 1 (g)	Week 2 (g)	Week 3 (g)	Week 4 (g)
A: ND	108.68 ± 0.00 d	117.68 ± 0.02bc	118.18 ± 0.01b	118.10 ± 0.00b	120.38 ± 0.01a
B: Negative	103.78 ± 0.01 c	118.78 ± 0.01b	219.68 ± 0.01a	220.87 ± 0.00a	222.97 ± 0.01a
C: Positive	103.38 ± 0.02c	116.38 ± 0.02b	117.45 ± 0.00b	118.93 ± 0.03a	119.96 ± 0.02a
D: BGN	101.79 ± 0.01 c	117.79 ± 0.02b	118.56 ± 0.05a	117.96 ± 0.00b	119.20 ± 0.01a
E: 10B90S	108.07 ± 0.03 c	118.06 ± 0.04b	119.12 ± 0.02b	119.48 ± 0.01b	120.98 ± 0.01a

0B100S—0% BGN; 10B90S—10% BGN; 20B80S—20% BGN; and 30B70S—30% BGN

ND normal diet, Positive—hypercholestemic diet without treatment, Negative—hypercholestemic diet treated with Simvastin; BGN—Bambara Groundnut powder; 10B90S—10% BGN

^abcMean values with the different superscript letter within same row are significantly different (p<0.05)

Conclusion

In this study, all the objectives were achieved where consumer acceptability and physico-chemical properties of nutritive BGN powdered mix were determined. Furthermore, microbiological changes and in-vivo assessment of the cholesterol-lowering effect of the mentioned product were determined. Sample 10B90S was the most acceptable to panellists, with acceptable appearance and flavor. BGN contained higher protein content and lower fat content compared to pure soy flour. The product was microbiologically stable under ambient storage after six months. In-vivo results showed that the nutritive BGN powdered mix was able to reduce total cholesterols in rats. Further research should be carried out to study the solubility, mesh size and antioxidant properties of BGN powder.