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Background Amaranth (Amaranthus spp.) is an underutilized, climate-resilient crop with the potential to improve food and nutritional security, particularly in sub-Saharan Africa. Despite its potential as a climate-resilient and nutritious crop, limited research on the genetic diversity and agronomic performance of locally adapted amaranth genotypes restricts understanding of key trait relationships and slows breeding progress. This study aimed to address this gap by evaluating the genetic variation and trait-based classification of six amaranth genotypes using univariate, bivariate, and multivariate statistical analyses on seven quantitative traits. Results Principal component analysis revealed that the first two components explained 63.6% of the total variation, effectively distinguishing genotypes based on key vegetative traits (leaf length, leaf width, stem girth, and plant height) and yield-related parameters (inflorescence length, grain yield and dry biomass). Cluster analysis identified two statistically distinct groups, with grain yield and inflorescence length contributing most to genetic divergence. Strong positive correlations among grain yield, stem girth, leaf length, and inflorescence traits suggest opportunities for indirect selection. Genotypes CK-BH-01 and LL-BH-04 exhibited superior performance in yield-related traits, making them as promising candidates for breeding improvement. Conclusion These findings provide a robust, data-driven framework for trait-based selection in amaranth breeding, supporting the development of high-yielding, stress-resilient varieties adapted to diverse agroecological zones.

This study assessed the chemical composition of amaranth leaves from six different accessions (MN-BH-01, PE-UP-BH-01, PE-LO-BH-01, CK-BH-01, NU-BH-01, and LL-BH-04) grown in various locations in Malawi. Key nutritional traits, including crude protein, calcium, zinc, iron, and potassium content, were analyzed, revealing significant variability influenced by genotype–environment interactions. MN-BH-01 exhibited the highest protein, calcium, zinc, and potassium levels, making it a promising candidate for nutritional enhancement. PE-UP-BH-01 had elevated iron content, while LL-BH-04 showed superior crude protein in certain locations. Nutrient composition varied significantly across different environmental conditions, emphasizing the impact of these interactions on nutrient accumulation. Cluster analysis and AMMI analysis identified consistent accessions (MN-BH-01 and NU-BH-01) valuable for breeding nutrient-rich varieties. Farmers preferred NU-BH-01 for its flavor, yield, and marketability, while MN-BH-01 was less favored due to its bitterness. These findings offer valuable insights for developing climate-resilient and biofortified amaranth varieties, contributing to food security and nutrition in Malawi and similar regions.

A study was carried out to determine beta-carotene retention and acceptability of selected products made from two provitamin-A maize varieties grown in Malawi, namely, MH43A and MH44A. Beta-carotene retention in the provitamin-A maize products was determined by using a “completely randomised block design” (CRBD) whereby the maize varieties (replicates) were treated as fixed blocks, and similar treatments (analytical tests) were applied in each block. Acceptability of the provitamin-A maize products was determined in 6 to 23-month-old children and their caregivers using a cross-sectional design. Results showed that in three maize products, namely, porridge, maize meal, and fermented maize beverage, there was an increase in beta-carotene, with apparent retentions of 111.13%, 170.27%, and 138.22% for MH43A and 156.50%, 207.13%, and 126.17% for MH44A varieties, respectively. Results on pregerminated maize flour produced from MH43A and MH44A maize varieties showed lower beta-carotene apparent retention values of 63.3% and 84.7%, respectively. Results on acceptability showed that most of the caregivers (47.1%) preferred porridge prepared from MH43A flour compared to porridge prepared from MH44A (30.6%) and the control variety (MH26-white maize) (22.4%). For roasted maize, roasted white maize grains (49.6%) were more preferred compared to the two provitamin-A varieties. Results on acceptability with respect to children showed that most children (63.5% and 53.7%) who tested MH43A and MH44A porridge, respectively, consumed all the porridge. Results from this study have shown that there is a high acceptability of provitamin-A maize porridges amongst children prepared from MH43A (55.5%) and MH44A (51.9%) maize varieties. The study therefore recommends that provitamin-A maize varieties should be promoted through appropriate preparation methods that ensure high beta-carotene retention to address vitamin-A deficiency.

Purpose The purpose of this paper is to evaluate the changes in descriptive sensory properties and overall consumer acceptability of soymilk prepared from roasted soybeans. Design/methodology/approach In total, 12 purposively selected post graduate students majoring in Food Science conducted descriptive sensory analysis after being trained for 18 h in sensory analysis, while 75 untrained students conducted consumer acceptability test of soymilk prepared by roasting soybeans at a temperature of 110°C for 20, 40, 60, 80 and 100 min and at 120°C for 20 min. Findings Results have revealed that roasting soybeans improved sensory properties by significantly (p<0.05) decreasing the objectionable green, beany flavours and increasing sweet taste, viscosity and roasted flavour. Furthermore, results from the principal component analysis revealed that aroma and sweet taste were the most critical sensory attributes. In addition, it was found out that soymilk samples prepared by roasting soybeans at 110°C for 40 and 60 min and at 120°C for 20 min were significantly more acceptable than the control soymilk. Research limitations/implications The participants in this study were from one locality and predominantly soybean consuming community and therefore there is need to conduct the study in a different locality in order to validate the study findings. Practical implications The study can assist small scale processors that might not have access to lipoxygenase-free soybeans and other technologies for improving the quality of soymilk. Social implications The study can be used as a guide for connecting the food processers with the external world of consumption. Originality/value For the first time, the study findings have demonstrated that controlled soybean roasting can be a useful strategy for improving soymilk sensory properties and consumer acceptability. The findings in this study can be usefully used in the quality control of soy bean-based products.

This study evaluated and compared the phytochemical and antioxidant properties of the solvent extracts of Azadirachta indica A. Juss and Vernonia amygdalina Del leaves . Methanolic and aqueous extracts showed high ( P ≤ 0.05) extract yields (in %), compared to chloroform and ethyl acetate extracts from both V. amygdalina and A. indica leaves. The study exhibited high phytochemical content in methanol and aqueous extracts compared to chloroform and ethyl acetate extracts, confirming the potential for medicinal use. V. amygdalina methanol and aqueous extracts had higher ( P ≤ 0.05) total phenolic content (TPC), in mg GAE/gDW, (158.810±0.846 and 217.883±0.265, respectively) than chloroform (37.574±0.118) and ethyl acetate (104.758±0.236) but higher ethyl acetate content in A. indica extracts. Low polar solvents extracted high ( P ≤ 0.05) total flavonoids, in mgQE/gDW, (367.051±0.858 and 149.808±0.009) compared to high polar solvents (14.863±0.071 and 54.226±0.014 ) in V. amygdalina while as in A. indica leaf extracts, low polar solvents showed high TFC ( 658.469±3.451 and 275.288±10.490) compared to high polar solvents (26.312±0.063 and 48.858±0.063) respectively. In vitro total antioxidant capacity, in mg/g, was higher in polar solvents than in low-polar solvents, ranging from 34.300±1.784 to 121.015±6.839 for A. indica ethyl acetate and methanolic extracts. A strong correlation between TPC and tannic acid content was observed, except in A. indica methanolic extracts of A. indica . Ferric reducing power was high, except for V. amygdalina chloroform and methanol leaf extracts, which were lower ( P≤ 0.05) than that of the standard ascorbic acid. The study revealed that high polar solvents, such as methanol and water, are more efficient in the extraction of antioxidants from A. indica but lower in V. amygdalina extracts. High phytochemical content and antioxidative capacity could be significant in treating various diseases in humans.

In this study, the flavour-enhancing properties of the Maillard reaction products (MRPs) for different systems consisted of different peptides (sunflower, SFP; corn, CP and soyabean SP) with, xylose and cysteine were investigated. Maillard systems from peptides of sunflower, corn and soyabean with xylose and cysteine were designated as PXC, MCP and MSP, respectively. The Maillard systems were prepared at pH of 7.4 using temperature of 120C for 2 h. Results showed that all systems were significantly different in all sensory attributes. The highest scores for mouthfulness and continuity were observed for MCP with the lowest peptides distribution between 1000 and 5000 Da, known as Maillard peptide. This revealed that the MCP with the lowest Maillard peptide content had the strongest “Kokumi” effect compared to the other MRPsand demonstrated that “kokumi effect” of MRPs was contributed by not only the “Maillard peptide” defined by the molecular weight (1000–5000 Da). Results on sensory evaluation after fractionation of PXC followed by enzymatic hydrolysis showed no significant differences between PXC, P-PXC and their hydrolysates. This observation therefore confirmed that the presence of other contributors attributed to the “Kokumi” effect rather than the Maillard peptide. It can be deduced that the unhydrolyzed crosslinking products might have contributed to the “Kokumi” effect of MRPs. The structures of four probable crosslinking compounds were proposed and the findings have provided new insights in the sensory characteristics of xylose, cysteine and sunflower peptide MRPs.

In this study, the effect of gallic acid on mechanical and water barrier properties of zein-oleic acid 0–4 % composite films was investigated. Molecular weight distribution analysis was carried out to confirm gallic acid induced cross linking through change in molecular weight in fraction containing zein proteins. Results revealed that gallic acid treatment increased tensile strength from 17.9 MPa to 26.0 MPa, decreased water vapour permeability from 0.60 (g mm m −2  h −1 kPa −1 ) to 0.41 (g mm m −2  h −1 kPa −1 ), increased solubility from 6.3 % to 10.2 % and marginally increased elongation at break from 3.7 % to 4.2 % in zein films only. However, gallic acid treatment in zein-oleic composite films did not significantly influence mechanical and water barrier properties and in most instances irrespective of oleic acid concentration, the properties were negatively affected. Results from scanning electron microscopy showed that both gallic acid treated and untreated zein films and composite films containing 3 % oleic acid had a compact and homogeneous structure while those containing 4 % oleic acid had inhomogeneous structure. The findings have demonstrated that gallic acid treatment can significantly improve mechanical and water barrier properties especially in zein films only as opposed to when used in composite films using zein and oleic acid.

The sensory characteristics and antioxidant capacity of Maillard reaction products (MRPs) from two substrates namely sunflower free amino acid and peptides, xylose with and without cysteine model systems (AXC, AX, PXC and PX, respectively) were evaluated and compared. The model systems were heated at 120 °C for 2.0 h and a pH of 7.4. Results showed that AXC had greater meat-like flavour and umami taste, while PXC showed great mouthfulness and continuity taste, and AX and PX showed higher caramel-like flavour and bitter taste. The addition of cysteine was found to accelerate high molecular weight peptide degradation while suppressing low molecular weight cross-linking and colour formation in PXC and AXC. Furthermore, it was observed that sensory attributes of MRPs were not significantly affected by the peptides size. Results also showed that caramel-like flavour and bitter taste were significantly and positively correlated with furans and most of the nitrogen-containing compounds while these compounds had significant and negative impact on mouthfulness, continuity and meat-like flavour. Additionally, sulphur-containing compounds showed significant and positive influence on meat-like flavour, while PXC and PX showed higher antioxidant activities than AXC and AX. It can therefore be concluded that sunflower peptides MRPs can be a good precursor of flavour enhancers with high antioxidant activity, while sunflower free amino acid MRPs can be used to produce meat-like flavour enhancers.

It is generally acknowledged that despite the superior nutritional value of soymilk, the presence of off-flavours catalysed by lipoxygenase (LOX) activities has to some extent negatively influenced the overall acceptability of soymilk in consumers. In this current study, the effect of roasting soybeans at different temperatures (110–130 °C) and times (20–120 min) on physical, chemical properties and LOX activity of soymilk was investigated in order to establish optimum soybean roasting conditions for developing nutritious and LOX free soymilk. Results have revealed that subjecting soybeans to increased roasting temperature and time negatively affected physical chemical properties of soymilk by decreasing the yield, solid content, colour and nutritive value. On the other hand, roasting soybeans at a relatively low temperature of 110 °C for 80 min significantly inactivated LOX but retained adequate protein content in soymilk. The findings of this study have demonstrated that careful selection of roasting conditions can be a useful strategy for inactivating LOX activity in development of a more acceptable soymilk product.

Compared to other processing methods used in soybeans, roasting has received limited attention in soymilk processing despite its known potential role in improving soymilk quality. In this study, the effect of soybean roasting at 110 °C for 20 to 100 min and at 120 °C for 20 min on the distribution of soymilk volatile compounds, antinutritional factors and storage parameters: pH, total titratable acidity, emulsion stability (ES) and rheology were investigated and comparison was made with the control sample prepared from soybeans which were not roasted. Results have shown that roasting soybeans improved soymilk properties by significantly decreasing the levels of each of the following objectionable volatile compounds: hexanal, 1-hexanol and Furan, 2-pentyl respectively from 43.58% to a minimum level of 17.95, 11.67–2.28 and 4.09–0.82%. In addition, the levels of trypsin inhibitors were considerably decreased from 5.86 to 1.91 mg/gm thus reducing the overall heat treatment time of the soymilk from 19.4 to 9.9 min. ES increased significantly from 23.97 to 102.84 min while viscosity at the shear rates of 0.1 and 1.0/s decreased respectively from 3.00 and 0.73 to 0.27 and 0.03 Pa s. Furthermore, all the samples were found with the behavior flow indices values of less than unity (0.16–0.38 respectively) suggesting that they were pseudo plastics. From the results, it can therefore be concluded that careful selection and application of soybean roasting parameters in terms of temperature and time can be a useful strategy in improving the quality of soymilk.