Protein energy malnutrition remains a huge burden in Sub-Saharan Africa. Principally, it is due to children being fed on millet gruels which are high in carbohydrates, and low protein. Moreover, they contain significant amounts of anti-nutrients such as phytates, phenols and tannins. Compositing of malted finger millet flour with other flours has potential for improving the nutritional quality and sensory attributes of these foods. The objective of this study was to determine the effect of compositing malted finger millet flour with cowpea on the anti-nutritional contents and sensory properties of formulated baby weaning food. Mixing selected improved finger millet varieties with precooked cowpea flour was based on WHO recommended levels. There was a significant (p < 0.05) reduction in total phenolic content, tannin content and phytic acid by 41%, 50%, and 44%, after compositing with malted finger millet and precooked cowpea at 10.32%, 21.26% and 32.75%, respectively. Cooking process significantly reduced amount of trypsin inhibitors, and other anti-nutrients both in cowpea and complementary porridge. Loadings from principal component analysis (PCA) of 17 sensory attributes of porridge showed that approximately over 80% of the variations in sensory attributes were explained by the first four principal components. Reductions in texture attributes (stickiness and viscosity) and astringency aftertaste corresponded to increase in overall aroma and flavour of the porridge in terms of malty flavour and aroma. Although inclusion of 32.75% precooked cowpea gave the highest reduction in anti-nutrients, it resulted in cooked cowpea flavour. For consumer acceptability , it may require masking by use of commercial flavours. Therefore this work shows that malted finger millet-pre - cooked cowpea have potential to be used in formulating cultural acceptable complementary food.
Weaning is the art of introducing semi-solid or solid food to infant life or complete discontinuation of breast milk by the introduction of semi-solid or solid food to the diet. Hence it involves expanding the infant’s diet to include other drinks and food rather than infant formula or breast milk [
Appropriate nutritional intake is important especially for infants, because it is the most critical stage of human development [
Finger millet (Eleusine coracana) stands as the sixth most important cereal grain in the world in terms of production. It sustains one-third of the world’s population. It is able to grow to a height of 0.4 - 1.0 m while the length of its panicles varies between 3 and 13 cm [
Cowpea is a drought and heat tolerant crop that is able to survive arid or semi-arid soil conditions experienced in sub-Saharan-Africa. In Kenya, where there are many poor subsistence farmers, cowpea could be a suitable alternative to expensive sources of protein such as meat and fish, because of its unique attributes and low agronomical requirement in terms of [
Various researchers have studied the nutritional and sensory quality of different food products with varying levels of cowpea. Examples include, porridge made from sorghum-cowpea [
The study was conducted at Guildford Dairy Institute, Department of Dairy and Food Science and Technology, Egerton University. Anti-nutrients determination was carried out at Kenya Agricultural and Livestock Research Organisation (KALRO) food laboratory in Njoro, Kenya and Biotechnology Laboratory at Egerton University, Kenya. Two, improved finger millet varieties were sourced from Egerton University Agro-Science Park, and were previously grown in a low altitude environment (Bomet County, Kenya). Improved cowpea varieties were Kundesoko and Kundefaulu sourced from KALRO Katumani Research Centre in Machakos County. The finger millets used had the following attributes: Snapping Green Early is easy to harvest and thresh and KNE 741 variety used is super early in maturity and suitable to low altitude. Kundesoko is a dual variety, high yielding, with long pods that are mostly above canopy for easy harvesting, while, Kundefaulu brown coloured, with grain that are large and with long pods loosely attached to pedicel, hence preferred by farmers as it fetches better price in the market.
Preparation of malted finger millet flour
Malting of the finger millet was carried out with modification as described by [
Preparation of precooked cowpea flour
Mature and dry grains (1 kg) were cleaned, which involved removing of foreign matter, broken seeds and immature seeds. The grains were then washed using tap water, and placed in metallic pot; tap water was then added until the grains were all submerged. They were cooked in boiling water (93˚C) for approximately 1 h, and then dried in an oven set at 50˚C to a moisture content of 10%. Dried grains were then milled using a Microphyte lab disintegrator model Fz102 (Tianjin, China), fitted with 500-μm sieve to give whole grain flour, and then stored at 9-10˚C until further analyses.
Preparation of composite flours
Malted finger millet and precooked cowpea flours were composited at 10.34%, 21.26% and 32.75% to reflect 9 - 13 g per day, protein requirements of the infants 1 to 3 years old as outlined by [
Preparation of porridge flours
Composite flour (30 g) was mixed with 50-mL cold water to form a thick batter. Water (100 mL), in a metallic pot, was brought to boil and then the batter added with continuous stirring using a cooking stick until the mixture formed a viscous gruel. The porridge was steamed on low heat for 10 min and then cooled on plates, later dried in forced draft oven at 60˚C to a moisture content of 10%. Dried porridge was milled using a Microphyte lab disintegrator model Fz102 (Tianjin, China), fitted with 500-μm sieve to give flour, and then stored at 9˚C - 10˚C for further analyses.
Determination of moisture content
Moisture content of the samples was determined using oven-drying method according to AACC International [
Determination of total phenols content
Total phenolics of the samples were analysed using the Folin-Ciocalteu method [
Determination of condensed tannin content
Modified Vanillin-HCl in methanol method [
Determination of phytic acid content
Phytic acid analysis was based on precipitation of phytate [
Phytate P mg/100g sample = [Fe (μg) × 15]/Weight of sample (g).
Recruitment and screening of the panel
Egerton university Department of Dairy and Food Science and Technology students, and academic staff who were willing to consume finger millet porridge, and had some experience of descriptive sensory evaluation and did not suffer from any food allergies, were invited through telephone, emails, and notices to participate in sensory evaluation. Twenty individuals responded, and attended an introduction session. Ten persons were already trained panellists: of these, nine confirmed their availability. They were screened for sensory acuity, using screening methods; identification tastes (sweet, salty and sour) and identification of sensory attributes that describe taste, flavour and appearance of different complementary porridge. A final panel of ten judges: nine previously trained and one recruit were selected and used.
Training of the panel
The panel was trained for 4 days in 2 hr sessions per day, according to generic descriptive method described by [
Descriptor’ | Definition | Reference | Rating scale |
---|---|---|---|
Aroma | |||
Overall aroma intensity | Intensity of the aroma of porridge | 1-Not intense 7-Very intense | |
Malty porridge aroma | Intensity of aroma associated with malted finger millet | 7-Aroma of malted finger millet after 2 days of malting Snapping variety | 1-Not intense malty aroma 7-Strong malty aroma |
Cooked cowpea aroma | Intensity of aroma associated with cooked cowpea | 7-Aroma of boiled whole cowpea (Boiled for 60 min in excess water) | 1-Low cooked cowpea aroma 7-Strong cooked cowpea aroma |
Finger millet aroma | Intensity of aroma associated with millet | 7-Aroma of finger millet porridge with 25% solids | 1-Not intense finger millet aroma 7-Strong finger millet aroma |
Texture | |||
Coarseness | Extend to which grittiness or granules of porridge caused by small particles | 1-Not coarse 7-Very coarse | |
Viscosity | Force required to draw a liquid from a spoon over the tongue | 7-Thickness of Finger millet porridge with 25% solids | 1-Thin 7-Thick |
Stickiness | Ability of porridge to stick on the wall of glass | 1-Less sticky 7-Too sticky | |
Flavour | |||
Overall Flavour intensity | Overall flavour intensity of the porridge | 1-Not intense 7-Strong intense | |
Cooked cowpea flavour | Intensity of the flavour of cooked cowpea | 7-Flavour of boiled whole cowpea (Boiled for 60 min in excess water) | 1-Less cooked cowpea flavour 7-Strong cooked cowpea flavour |
Millet flavour | Intensity of flavour of cooked raw finger millet | 7 Flavour of finger millet porridge with 25% solids | 1-Not intense 7-Very intense |
Malty flavour | Intensity of flavour of cooked malted finger millet | 7-Flavour of malted finger millet after 2 days of malting Snapping variety | 1-Not intense 7-Very intense |
Burnt flavour | Intensity of flavour of porridge associated with burnt porridge residues | 7-Flavour malted finger millet porridge having 25% solids burnt during preparations | 1-Not intense 7-Very intense |
Sensation after swallowing the sample (Aftertaste) | |||
Malty aftertaste | Intensity of cooked malted finger millet porridge flavour perceived in the mouth after swallowing | 7-Aftertaste of malted finger millet after 2 days of malting Snapping variety | 1-Not intense 7-Very intense |
Cowpea aftertaste | Intensity of cooked cowpea flavour perceived in the mouth after swallowing | 7-Aftertaste of boiled whole cowpea (Boiled for 60 min in excess water) | 1-Not intense 7-Very intense |
Millet after taste | Intensity of aftertaste associated with cooked millet porridge perceived after swallowing porridge | 7-Aftertaste of finger millet porridge with 25% solids | 1-Not intense 7-Very intense |
Astringency | Dry feeling in the mouth after swallowing | 1-Not intense 7-Very intense | |
Presence of residue | Leaves particles of the grain in mouth and teeth | 1-Low 7-High |
Descriptive sensory evaluation of Porridge
Composite flour (100 g) was mixed with 200-mL cold water to form a thick batter. Water (350 mL), was brought to boil and then the batter added with continuous stirring using a cooking stick until the mixture formed a viscous gruel. The porridge was steamed on low heat for 10 min The porridge was then placed in well labelled different jars, and then maintained at 50˚C in a water bath, to keep the porridge warm for descriptive sensory evaluation.
Cooked porridge (50-mLportions) was served in glass ramekins kept warm in a water bath at 50˚C. The sensory evaluation of the porridge was conducted in a sensory evaluation room with individual booths. Panelists evaluated all samples in duplicate. Each panellist received six samples of porridge on glass ramekins, a serviette and a plastic disposable cup filled with filtered tap water for rinsing the mouth before and between tasting the samples. To avoid fatigue, three samples were tasted and after a 10 min break, the other three samples kept warm in a water bath at 50˚C, were tasted. The order of sample presentation of the samples was randomised for each panel. Seventeen descriptive terms, were used by the panellists, grouped under flavour, aroma, texture and aftertaste attributes as represented in
The effects of malting finger millet, compositing and cooking on the anti-nutrient content and sensory properties of the complementary porridge were evaluated using analysis of variance (ANOVA) based on a 5% level of significance. Significant differences between means were determined using Tukey’s honestly significance difference (HSD). Calculations were performed using Statistical Analysis System (SAS) version 9.3 at p < 0.05. Furthermore, principal component analysis (PCA) was performed to study sample relationships.
Effect of malting finger millet on total phenol of complementary porridge
Unmalted KNE 741 (control), had the highest amount of total phenols (condensed tannins, flavonoids and phenolic acids) at 2.32 mg CE /100 mg, (db) as compared to unmalted Snapping (control) at 1.26 mg CE /100 mg (db) (
Condensed tannins as mg CE/100 mg, (db) | Total Phenols as mg CE/100 mg, (db) | ||||||||
---|---|---|---|---|---|---|---|---|---|
Flour | Porridge | Flour | Porridge | ||||||
Millet variety | Composite | Unmalted + Cowpea | Malted + Cowpea | Unmalted + Cowpea | Malted + Cowpea | Unmalted + Cowpea | Malted + Cowpea | Unmalted + Cowpea | Malted + Cowpea |
Snapping | 0% (Control) | 0.61fg ± 0.06 | 0.34h ± 0.04 | 0.61e ± 0.03 | 0.35fh ± 0.00 | 1.26i ± 0.09 | 0.83h ± 0.03 | 1.09b ± 0.03 | 1.07b ± 0.09 |
10.34% PKS | 0.62f ± 0.06 | 0.35gh ± 0.02 | 0.62e ± 0.04 | 0.33h ± 0.03 | 1.44k ± 0.03 | 1.30c ± 0.05 | 1.03cd ± 0.03 | 1.01c ± 0.09 | |
21.26% PKS | 0.56h ± 0.04 | 0.37f ± 0.06 | 0.56f ± 0.02 | 0.38ef ± 0.05 | 1.50j ± 0.00 | 1.22e ± 0.05 | 0.92e ± 0.05 | 0.87e ± 0.26 | |
32.75% PKS | 0.53i ± 0.02 | 0.40e ± 0.04 | 0.53g ± 0.03 | 0.39e ± 0.05 | 1.54i ± 0.03 | 1.10g ± 0.03 | 0.85f ± 0.04 | 0.80f ± 0.11 | |
10.34% PKF | 0.59g ± 0.06 | 0.33h ± 0.09 | 0.55g ± 0.05 | 0.33h ± 0.06 | 1.76g ± 0.03 | 1.49b ± 0.09 | 1.05c ± 0.08 | 1.00c ± 0.10 | |
21.26% PKF | 0.55hi ± 0.02 | 0.32h ± 0.03 | 0.46h ± 0.04 | 0.34fh ± 0.07 | 1.70h ± 0.03 | 1.23e ± 0.07 | 1.13a ± 0.00 | 1.11a ± 0.27 | |
32.75% PKF | 0.50j ± 0.03 | 0.32h ± 0.11 | 0.47h ± 0.07 | 0.36f ± 0.00 | 1.68h ± 0.03 | 1.17f ± 0.07 | 1.11ab ± 0.03 | 1.02c ± 0.19 | |
KNE741 | 0% (Control) | 1.27a ± 0.02 | 0.64b ± 0.02 | 1.11a ± 0.03 | 0.62b ± 0.03 | 2.32a ± 0.05 | 1.36c ± 0.05 | 1.00d ± 0.03 | 0.92d ± 0.03 |
10.34% PKS | 1.11c ± 0.05 | 0.69a ± 0.03 | 1.00b ± 0.04 | 0.62b ± 0.02 | 2.24b ± 0.05 | 1.71a ± 0.09 | 1.14a ± 0.03 | 1.09ab ± 0.03 | |
21.26% PKS | 0.98d ± 0.04 | 0.64b ± 0.03 | 0.94c ± 0.03 | 0.61bc ± 0.02 | 2.10d ± 0.03 | 1.47b ± 0.19 | 1.04c ± 0.05 | 1.02c ± 0.03 | |
32.75% PKS | 0.84e ± 0.07 | 0.59c ± 0.10 | 0.76d ± 0.03 | 0.59c ± 0.00 | 2.09d ± 0.09 | 1.28d ± 0.05 | 0.94e ± 0.03 | 0.93d ± 0.05 | |
10.34% PKF | 1.15b ± 0.06 | 0.65b ± 0.03 | 0.94c ± 0.03 | 0.65a ± 0.02 | 2.16c ± 0.09 | 1.33c ± 0.05 | 1.03cd ± 0.12 | 1.03c ± 0.03 | |
21.26% PKF | 0.96d ± 0.03 | 0.61c ± 0.03 | 1.12a ± 0.04 | 0.60bc ± 0.03 | 2.01e ± 0.04 | 1.33c ± 0.07 | 0.88f ± 0.03 | 0.87e ± 0.05 | |
32.75% PKF | 0.86e ± 0.04 | 0.56d ± 0.02 | 0.77d ± 0.04 | 0.54d ± 0.04 | 1.97f ± 0.03 | 1.28d ± 0.05 | 0.98d ± 0.03 | 1.00c ± 0.03 |
Values are means ± standard deviations. Values of a parameter in a column, followed by different superscript letters are significantly different at p ≤ 0.05, n = 3, PKS—Precooked KundeSoko, PKF—Precooked KundeFaulu, CE—Catechin equivalent, db—dry weight basis.
the phenol content of the finger millet varieties. Polyphenols act as anti-feedants, phytoalexins, contributors to plant pigmentation and antioxidants therefore they have an important role in cereals such as finger millet and sorghum [
Effect of compositing malted finger millet with precooked cowpea on total phenols of complementary porridge
Addition of precooked cowpea, which had low amount of phenols, trypsin inhibitors and other anti-nutrients greatly, significantly (p < 0.05) influenced reduction of assayable phenols in the composites. This is illustrated by the high reduction in phenols of approximately 40% as compared to snapping at 0% (100% malted finger millet when malted snapping finger millet variety was composited with cowpea at 32.75%, (
The effect of cooking malted finger millet with precooked cowpea on total phenols of complementary porridge
Cooking resulted in significant (p < 0.05) reduction of phenol content of up to 8% in extractable phenol of the composite flours. This is probably due to structural binding of phenols to other macromolecules during cooking resulted in low assayable phenols. Chemical nature of the phenolic compounds, sample particle size, extraction methods and the assay method itself also influenced assayable phenols. The method used involved reduction-oxidation reaction during which at basic pH, the phenolate ion is oxidised, while phosphotungstic/phospho-molybdic acid complex reduced to chromogens (blue coloured solution) [
Effect of malting finger millet on condensed tannins of complementary porridge
KNE741 (0%), had the highest amount of tannins, which was significantly different at p < 0.05 from Snapping (0% control) (
Effect of compositing malted finger millet with precooked cowpea on condensed tannins of complementary porridge
Compositing resulted in approximately 21% reduction in condensed tannins when unmalted finger millet was composited with precooked cowpea at 10.34%, 21.26% and 32.75% levels. It had also a compound effect when malted finger millet was composited with precooked cowpea as it resulted in 18% reduction in condensed tannins. The reduction was attributed to addition of precooked cowpea that had low amount of tannins as compared to uncooked cowpea. Also, malting of finger millet resulted in low amount of tannins in the composites as discussed above resulting in low amount assayable condensed tannins in the composites formulated.
Effect of cooking malted finger millet with precooked cowpea on condensed tannins of complementary porridge
Cooking of the complementary foods resulted in significant (p < 0.05) decrease in assayable tannin content by approximately between 22% and 47% (
Effect of malting finger millet on phytic acid of complementary porridge
Snapping (control) showed a significant (p < 0.05) higher amount of phytate as compared to KNE741 (Control) variety, showing that variety had a significant effect on phytic acid in the grains [
Millet variety | Flour Porridge | ||||
---|---|---|---|---|---|
Composite | Unmalted + Cowpea | Malted + Cowpea | Unmalted + Cowpea | Malted + Cowpea | |
Snapping | 0% (Control) | 1252.14a ± 62.44 | 741.15ab ± 40.5 | 1090.60b ± 24.25 | 667.41b ± 46.33 |
10.34% PKS | 1186.65b ± 40.50 | 720.76b ± 23.60 | 1110.08a ± 24.68 | 644.88c ± 23.82 | |
21.26% PKS | 1129.51c ± 47.20 | 727.65b ± 61.36 | 1016.13c ± 23.82 | 646.65c ± 61.86 | |
32.75% PKS | 1071.13d ± 23.82 | 754.65a ± 23.38 | 908.16f ± 23.17 | 692.36a ± 24.03 | |
10.34% PKF | 1139.88c ± 23.82 | 687.15c ± 84.31 | 969.94d ± 22.73 | 552.15f ± 46.77 | |
21.26% PKF | 1047.76e ± 23.60 | 673.65cd ± 23.38 | 921.70ef ± 22.52 | 552.15f ± 23.38 | |
32.75% PKF | 1029.88f ± 23.82 | 627.29ef ± 23.17 | 969.94d ± 22.73 | 553.61f ± 41.63 | |
KNE741 | 0% (Control) | 1047.76e ± 23.60 | 584.51g ± 70.80 | 1016.13c ± 23.82 | 466.79i ± 23.17 |
10.34% PKS | 1038.15ef ± 23.38 | 611.76f ± 23.60 | 934.70e ± 22.52 | 568.43e ± 39.75 | |
21.26% PKS | 876.15h ± 23.38 | 633.15e ± 46.77 | 822.15h ± 40.50 | 534.88g ± 23.82 | |
32.75% PKS | 761.64j ± 23.60 | 667.41d ± 46.33 | 748.01j ± 40.87 | 516.60h ± 0.00 | |
10.34% PKF | 1034.14ef ± 40.88 | 666.26d ± 0.00 | 1015.59c ± 24.46 | 622.99d ± 48.06 | |
21.26% PKF | 979.64g ± 23.60 | 720.76b ± 23.60 | 866.60g ± 48.50 | 633.15cd ± 23.38 | |
32.75% PKF | 843.39i ± 47.20 | 727.65b ± 46.77 | 775.26i ± 23.60 | 680.79b ± 23.17 |
Values are means ± standard deviations. Values of a parameter in a column, followed by different superscript letters are significantly different at p ≤ 0.05, n = 3, PKS—Precooked Kundesoko, PKF—Precooked Kundefaulu, db—dry weight basis.
Effect of compositing malted finger millet with precooked cowpea on phytic acid of complementary porridge
When unmalted Snapping was composited with precooked cowpea it showed significant (p < 0.05) higher values of phytate as compared to KNE741. Unmalted KNE741 composited with precooked Kundesoko (PKS) at 32.75% had lowest amount of phytate. Compositing with precooked cowpea resulted in significant (p < 0.05) reduction of phytate by factor of 72% (
Effect of cooking malted finger millet with precooked cowpea on phytic acid of complementary porridge
Cooking resulted in 6% and 20%reduction of phytate in the complementary baby foods (
Effect of malting finger millet on sensory quality of complementary porridge
F-values from the analysis of variance showed a significance difference (p < 0.05) for all the 17 sensory attributes of the complementary porridge (
Effect of adding precooked cowpea flour on sensory quality of complementary porridge
Composite | Aroma | Texture | Flavour | |||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Overall intensity | Malty | cooked cowpea | finger millet | Coarseness | Viscosity | Stickiness | Overall flavour | Cooked cowpea | finger millet | Malty | Burnt | |
KNE741 (0%) | 1.4f ± 0.55 | 1.20g ± 0.45 | 2.0f ± 0.71 | 4.8c ± 0.45 | 5.6b ± 0.89 | 7.0a ± 0.00 | 7.0a ± 0.00 | 2.8e ± 0.84 | 1.8g ± 0.45 | 6.0b ± 0.71 | 1.4h ± 0.89 | 1.0g ± 0.00 |
KNE741 (21.26%) | 1.4f ± 0.55 | 1.20g ± 0.45 | 4.4c ± 1.14 | 4.0e ± 1.41 | 3.4e ± 0.55 | 7.0a ± 0.00 | 7.0a ± 0.00 | 4.0d ± 0.71 | 4.8d ± 0.45 | 4.6c ± 1.34 | 1.4h ± 0.89 | 1.2g ± 0.45 |
KNE741 (32.75%) | 2.4e ± 1.34 | 1.8f ± 0.84 | 4.6c ± 0.89 | 4.6cd ± 0.55 | 4.8c ± 1.10 | 6.6b ± 0.55 | 6.6b ± 0.55 | 1.8f ± 0.45 | 6.0a ± 1.22 | 4.0d ± 0.71 | 3.8e ± 0.84 | 3.6cd ± 0.89 |
MKNE741 (0%) | 1.4f ± 0.55 | 5.8b ± 1.10 | 4.2cd ± 1.10 | 4.6cd ± 0.89 | 3.8de ± 1.10 | 2.0g ± 0.00 | 3.0d ± 1.00 | 5.6b ± 0.89 | 3.6ef ± 0.55 | 3.8d ± 1.10 | 6.6a ± 0.55 | 4.6a ± 1.14 |
MKNE741 (21.26%) | 5.4b ± 1.52 | 5.2c ± 0.84 | 5.6a ± 0.89 | 4.4d ± 0.89 | 3.4e ± 0.89 | 2.4f ± 0.89 | 1.4f ± 0.55 | 4.8cd ± 1.10 | 3.4f ± 0.55 | 4.4cd ± 0.89 | 5.6b ± 0.89 | 3.8c ± 1.10 |
MKNE741 (32.75%) | 4.6c ± 0.89 | 3.6d ± 0.89 | 4.4c ± 0.55 | 4.4d ± 0.55 | 2.4f ± 1.34 | 3.4d ± 0.89 | 3.2d ± 0.45 | 4.8cd ± 1.10 | 4.6d ± 0.55 | 4.4cd ± 0.89 | 4.8d ± 1.10 | 4.4ab ± 0.89 |
SNAPP (0%) | 5.4b ± 1.34 | 2.4e ± 0.89 | 4.4c ± 0.55 | 6.0a ± 0.00 | 4.6cd ± 0.89 | 6.8ab ± 0.45 | 7.0a ± 0.00 | 4.8cd ± 1.10 | 2.0g ± 0.00 | 6.8a ± 0.45 | 2.6g ± 0.89 | 2.6e ± 0.89 |
SNAPP (21.26%) | 4.0d ± 0.71 | 2.6e ± 0.89 | 3.2e ± 0.84 | 5.6b ± 0.55 | 6.0a ± 1.0 | 6.6b ± 0.55 | 6.4b ± 0.55 | 3.6d ± 0.55 | 3.8e ± 0.45 | 6.0b ± 0.71 | 3.2f ± 0.45 | 1.8f ± 0.45 |
SNAPP (32.75%) | 3.8d ± 1.30 | 3.4d ± 0.55 | 5.0b ± 0.71 | 5.6b ± 0.55 | 4.6cd ± 0.89 | 6.2c ± 1.10 | 5.6c ± 0.89 | 5.6b ± 0.55 | 5.6b ± 0.55 | 4.8c ± 0.45 | 3.8e ± 0.45 | 3.6cd ± 0.55 |
MSNAPP (0%) | 6.0a ± 1.00 | 5.8b ± 0.84 | 3.6de ± 0.89 | 3.6f ± 0.55 | 2.4f ± 0.45 | 2.2fg ± 0.45 | 2.0e ± 0.00 | 6.2a ± 0.89 | 1.8g ± 0.55 | 3.6de ± 0.55 | 6.6a ± 0.55 | 4.4ab ± 0.89 |
MSNAPP (21.26%) | 5.8ab ± 0.45 | 6.2a ± 0.84 | 3.4de ± 0.89 | 4.0e ± 0.71 | 4.2d ± 1.30 | 1.8g ± 0.45 | 1.6f ± 0.55 | 5.2bc ± 0.84 | 5.0cd ± 0.71 | 3.2e ± 0.45 | 5.6bc ± 0.89 | 4.2b ± 0.45 |
MSNAPP (32.75%) | 5.4b ± 0.89 | 5.0c ± 0.71 | 3.8d ± 0.84 | 4.0e ± 1.0 | 3.2e ± 0.45 | 2.8e ± 0.45 | 3.2d ± 0.45 | 5.0c ± 0.00 | 5.2c ± 0.45 | 2.6f ± 0.55 | 5.4c ± 0.55 | 3.4d ± 0.55 |
Values are means ± standard deviations. Values in a column followed by different letter notations are significantly different at p ≤ 0.05 n = 5. M—Malted.
Values are means ± standard deviations. Values in a column followed by different letter notations are significantly different at p ≤ 0.05, n = 5.
Samples composited at 21.26% and 32.75% had a significant effect (p < 0.05) on malty and cooked cowpea flavour characteristics with the latter predominating as the ratio increased. There was also a concomitant reduction in astringency aftertaste as more cowpea was added. Cooked cowpea, instead of characteristic beany flavour associated with most legumes, contain a roasted nut flavour due to action of sugars and protein when they exposed to drying temperatures after cooking. This resulted a significantly (p < 0.05) higher values in composites composted at 32.75% than 21.26%.
PCA characteristics of sensory attributes of complementary porridge
Principal component analysis was used to extract important information from the heterogeneous data, and reduce set of correlated variables to uncorrelated measures (principal components) without loss of original information [
An attribute that was uniquely prominent in PC3, was roasted nut flavour (described by panellists as cooked cowpea flavour), associated with compositing precooked of cowpea and had a positive loading of approximately 0.80 that influenced the overall flavour and aroma intensity of complementary finger millet porridge. The attribute seemed to be unfamiliar to complementary porridge consumers, because of its low correlation coefficient (−0.10) which was not significant to overall flavour. The findings were in agreement with Kayitesi et al. [
Correlations loading plot for the complementary sensory attributes for the first three PCs represented in
Moreover, millet flavour and millet aftertaste were closely located having a positive correlation, but negatively correlated to cooked cowpea aroma and cowpea aftertaste, located in the opposite quadrant, which can be attributed to varying level of precooked cowpea flour used. Malty flavour, malty aftertaste and malty aroma were located close to overall flavour and aroma sensory attributes, showing that the three parameters were important in defining the flavour of the complementary porridge. In the present work therefore, showed that, composites that were viscous, stick and astringent aftertaste attributes were lowly rated hence less desired. Negative correlation of viscosity and stickiness in
In
score plot represents loadings of sensory attributes in the multivariate space of two PC score vectors. From the figures, two samples were clearly distinguished based on the sensory attributes. Two varieties used had distinguishable sensory attributes (
In
Malting decreases anti-nutrient content with a concomitant increase in nutrient profile of complementary foods. In the present study, tannin content, phytic acid and total phenol content notably decreased by 50%, 44% and 41%, respectively, after compositing with malted finger millet and precooked cowpea. In addition, malting of finger millet varieties positively influences the sensory attributes in terms of malty flavour, malty aroma and malty aftertaste as they were closely related and were negatively correlated to viscosity and stickiness. Furthermore, malty flavour and malty aftertaste significantly influence overall flavour, based on correlation coefficient results of 0.53 and 0.54 respectively. Based on these observations it is feasible to composite malted finger millet and precooked cowpea at 32.75%, however, this high level results in a distinctive cooked cowpea flavour that will have to be masked by commercial flavours available in commercial market. Therefore, compositing malted finger millet with precooked cowpea can be used in formulating a cultural acceptable complementary food that can be used to curb Protein energy malnutrition in Kenya.
The research was funded by the Centre of Excellence for Sustainable Agriculture and Agribusiness Management (CESAAM), World Bank funded project at Egerton University, Kenya. Thanks to Agro-science park for the supply of seed varieties.
The authors declare no conflicts of interest regarding the publication of this paper.
Syeunda, C.O., Anyango, J.O. and Faraj, A.K. (2019) Effect of Compositing Precooked Cowpea with Improved Malted Finger Millet on Anti- Nutrients Content and Sensory Attributes of Complementary Porridge. Food and Nutrition Sciences, 10, 1157-1178. https://doi.org/10.4236/fns.2019.109084