Sensory evaluation and chemical composition of Solanum nigrum and Solanum torvum herbal tea and spice.

Herbal teas are ingested for various purposes and by diverse populations across the globe. There is a growing recognition among individuals of the advantages associated with the use of this beverage, leading to a heightened demand for the manufacture of herbal tea derived from therapeutic plants. Spices on the other hand add flavour to food but could pose harm if it is high in phytates and oxalates. The objective of this study was to develop natural spices and herbal tea with health beneficial properties using Solanum nigrum and Solanum torvum berries. Herbal tea samples from S. nigrum were prepared by sorting berries, maceration, divided into two (fermenting at 18 °C and non-fermenting) and dried at 60 °C for 12 h in a hot oven. Spices from S. torvum and S. nigrum were prepared by removing the berries from the stalk, freeze-drying and smooth milling into fine powder. In addition, antinutrient, phytochemical and sensory evaluation studies were conducted on these spices and herbal teas. A nine-point hedonic scale was utilized for the purpose of conducting a consumer acceptability sensory evaluation test using 101 untrained panelists. Data was then analyzed by t-test, one-way analysis of variance (ANOVA) and the level of significance (p < 0.05) was assessed using Tukey's and Dunnett's multiple comparison tests. The panellists expressed a favourable perception towards Solanum nigrum unripe unfermented green herbal tea (6.65 ± 2.08) as compared to the other formulated teas due to the components working together in a way that produces a nice tea sample. Both Solanum nigrum and Solanum torvum spices contained various levels of catechins, saponins, flavonoids, oxalates, phytates and tannins comparable to literature. The herbal tea samples exhibited a range of catechin content, varying from 0.255 to 0.756 mg/g. The antioxidant activity of the various herbal tea samples ranged from 66.37 ± 0.24 to 78.53 ± 0.18 µg/mL GAE as determined by the DPPH free radical assay Fermented black herbal teas recorded higher total phenols (2.80 ± 0.09d), total flavonoids (21.84 ± 1.84c) and showed greater antioxidant activity (78.53 ± 0.18a) as compared to the unfermented green herbal teas. The process of fermentation resulted in a decrease in pH from 7.22 to 6.53 within a period of 12 h. The Total Titratable Acidity (TTA) grew as the fermentation period progressed, whereas the Total Soluble Solids (TSS) decreased. Phytates were the least antinutrients among the two Solanum species accounting for 0.02 mg/100 g and 0.03 mg/100 g in S. torvum berries (STBs) and (S. nigrum berries) SNBs respectively.

Gender-Disaggregated Consumer Testing and Descriptive Sensory Analysis of Local and New Yam Varieties.

Gender-disaggregated sensory evaluation has become an essential element that could enhance breeding activities by increasing the adoption of new varieties. The effect of age, sex and geographical location on descriptor preferences for boiled and pounded yam were studied using descriptive and consumer testing. Attributes with definitions and measurement scales were used to generate lexicons for boiled and pounded yam. Analytical tools employed for the inferential statistics were the independent t-test, analysis of variance, Kruskal-Wallis test, Mann-Whitney test and relative importance index (RII). Descriptive testing showed that all the D. rotundata varieties were good for boiling and pounding. The D. alata varieties afase soanyinto and afase biri were most liked, while afase pa and ahodenfo were disliked. Age had no significant effect on descriptor preferences. Being a female or male, however, influenced preferences for pounded yam descriptors such as mouldability, lumpiness and colour. The RII for the D. rotundata varieties (0.22-0.28) showed that they are all good varieties for boiling and pounding. The local D. alata varieties were still highly acceptable compared the new CRI varieties due to the aroma. Rural consumers preferred all the descriptors of boiled D. rotundata than urban consumers, whereas urban consumers liked the pounded yam varieties better than the rural consumers. Availability of the new yam varieties on local markets could therefore increase consumption and improve adoption.

The effect of gender on end-user preferences for yam quality descriptors.

Improving the effectiveness of breeding programs could be achieved by breeding for consumers' preferences. The relationship between gender and consumer preferences for yam was studied using purposeful sampling for key informants, focus group discussions (FGDs), and individual interviews. Data from qualitative interviews were transcribed and quantitative data analyzed using SPSS (version 20). Cramer's V (Phi) and logistic regressions were used to explain the observations. Males prioritized income-generating varieties over females, while females ranked tuber morphological characteristics high. Sex-based preference for yams showed that moldability and sweet taste are preferred by both females and males. Moderately hard boiled yams and shelf stable food products are liked by males, whereas aroma is rated highly by females. Males described yams that have a longer digestion time as "heavy" and preferred such varieties. Watery tubers and tubers not turning brown are important characteristics during processing. The Phi of 0.157 and 0.163 for sex and ethnic groups show moderate to strong associations between choices for descriptors by females, males, and various ethnic groups. These findings imply that gender disaggregation of information on preference for yam quality descriptors should be considered in future yam breeding programs as it may improve adoption rate and enhance food security.

Development and Sensory Assessment of Ready-to-Eat Breakfast Cereal.

There is a gradual change in the eating trend of Ghanaians. People now prefer convenient semiprocessed foods as breakfast meals to raw ones. These breakfast meals make use of cereals and grains, which often suffer postharvest losses. Thus, this study was aimed at adding value to these food crops by producing a nutritious convenient breakfast meal in the form of flakes using yellow maize and coconut as main food components. Five different formulations of percentages, maize against coconut (80/20, 77.5/22.5, 75/25, 72.5/27.5, and 70/30), were developed using the Design-Expert's D-optimal design to produce the breakfast meals through drum drying and the products assessed for acceptability by consumer panel. Panellists rated the produced cereal high in overall acceptability during the sensory evaluation. The overall acceptability decreased with decreasing coconut percentage in the cereal product. The 70/30 formulation was most preferred by panellist. The protein, fat, ash, fibre, carbohydrate, and energy contents in all five formulations increased significantly after processing. Coliform count and Bacillus cereus counts were <10 cfu/g.

Cashew Apples in Ghana: Stakeholders' Knowledge, Perception, and Utilization.

Cashew (Anacardium occidentale), a crop projecting Ghana internationally beside cocoa, is usually cultivated for its nut, for both local and international markets. The cashew apple is underutilized in many African countries. This study is aimed at determining the knowledge, perception, and utilization of cashew apples in Ghana among stakeholders in the cashew value chain. Results from the study showed that the cashew industry consisted of farmers (89.1%), nut buyers (6.8%), extension officers (3.5%), and processors (0.6%) with uneven distribution of males (66.2%) and females (33.8%). Cashew apple utilization was low (<10%), though 84.37% had in-depth knowledge on the health benefits and value-added products made from the apples. Cashew apple is mainly utilized as fresh fruits or juice, with minor uses as an ingredient in food preparation, animal feed formulation, and production of mushroom, weedicide, ethanol, and manure. The cashew apple processors identified high cost of processing equipment, perishability of apples, lack of capital, market, technical know-how, and government support as challenges. Based on these findings, education of the stakeholders on value addition or processing of the apples at household and industrial levels and provision of stimulus packages to private processors are recommended to maximize cashew apple utilization in Ghana.

Effect of pretreatment on physicochemical, microbiological, and aflatoxin quality of solar sliced dried ginger (Zingiber officinale Roscoe) rhizome.

Pretreatment of fruit and vegetables is necessary to reduce microbial proliferation and to preserve color of the produce. The effect of drying and pretreatment with potassium metabisulfite (KMBS) of concentrations 0.0%, 0.1%, 0.15%, 0.2%, and 1.0% and blanching at 100°C and 50°C using a tent-like concrete solar (CSD) dryer as compared to open-sun drying (OSD) of yellow ginger rhizomes was investigated using routine methods. The total color change and residual sulfur dioxide (SO2) were analyzed. KMBS reduced the yeast and mould load significantly from 3.6 × 104 ± 1.4 × 103 CFU/g in 0.0% (control) to <10 CFU/g in 1.0% KMBS and 100°C blanched fresh samples. Drying of the fresh samples for 5 days increased the yeast and mould load of all the treatments to as high as 1.15 × 105 ± 2.12 × 104 CFU/g for the 1.0% KMBS. Overall, the CSD had fewer microbial loads than the OSD but it was not significant. Aflatoxins and Salmonella sp. were not detected in any of the samples. The sulfur dioxide residue (SO2) for KMBS pretreated samples increased as the concentration of KMBS increased with the CSD retaining slightly higher amount than the OSD. The total color change index increased with increase in KMBS, and drying further increased the total color change index. On the whole, the blanched samples had the least color change among the pretreatments with 100°C CSD showing the least change among the dried samples.

The effect of vinegar and drying (Solar and Open Sun) on the microbiological quality of ginger (ZINGIBER OFFICINALE ROSCOE) rhizomes.

This study evaluated the influence of 10% vinegar and solar drying using two solar dryers and open-sun drying on the microbiological quality of ginger (Zingiber officinale Roscoe) rhizome. The rhizomes were analyzed for bacterial, mold, and Salmonella populations in the raw state, which were water-washed and soaked in 10% vinegar, and in dried form. The fungal population was isolated and identified. Fresh and dried ginger rhizome contained both bacterial and fungal population in the range of 3.0 x 102 ± 1.14 x 102 to 2,180 x 109 ± 70.7 x 109 CFU/g. The stainless steel solar dryer had fewer fungal loads among the drying methods. Aspergillus and Penicillium species of mycotoxin-producing potential were identified. The 10% vinegar as pretreatment showed no significant difference (p ≤ .05) in the bacterial population reduction but in the fungal population reduction. Growth of fungi in fresh and dried ginger extracts was lower compared with growth in Potato Dextrose Broth.

Utilizing cocoyam (Xanthosoma sagittifolium) for food and nutrition security: A review.

The critical role of indigenous crops in the socioeconomic growth of developing nations has necessitated calls for accelerated exploitation of staples. Cocoyam, Xanthosoma sagittifolium, is food for over 400 million people worldwide and is the most consumed aroid in West Africa. However, it remains an underexploited food resource. This study reviews existing literature and also makes use of primary data from interviews with indigenous cocoyam farmers, processors, consumers, and cocoyam scientists in the research Institutes of Ghana, to provide insight into existing nomenclature of the species, indigenous knowledge on food uses, nutritional value, and potential novel food applications of cocoyam. Adaptable technologies in conformity to new trends in food science that could be employed for in-depth molecular studies and further exploitation of the crop are also discussed. It is envisaged that the provided information would contribute to global efforts aimed at exploiting the full potential of indigenous crops for sustainable food and nutrition security.

Characteristics of Xanthosoma sagittifolium roots during cooking, using physicochemical analysis, uniaxial compression, multispectral imaging and low field NMR spectroscopy.

To effectively promote the industrial utilization of cocoyam (Xanthosoma sagittifolium) roots for enhanced food sustainability and security, there is a need to study their molecular, mechanical and physicochemical properties in detail. The physicochemical and textural characteristics of the red and white varieties of cocoyam roots were thus analysed by low field nuclear magnetic resonance relaxometry, multispectral imaging, uniaxial compression testing, and relevant physicochemical analysis in the current study. Both varieties had similar dry matter content, as well as physical and mechanical properties. However, up to four fast-interacting water populations were observed in the roots, dependent on the root variety and their degree of gelatinization during cooking. Changes in the relaxation parameters indicated weak gelatinization of starch at approximately 80 °C in both varieties. However, shorter relaxation times and a higher proportion of restricted water in the white variety indicated that this variety was slightly more sensitive towards gelatinization. A strong negative correlation existed between dry matter and all multispectral wavelengths >800 nm, suggesting the potential use of that spectral region for rapid analysis of dry matter and water content of the roots. The small, but significant differences in the structural and gelatinization characteristics of the two varieties indicated that they may not be equally suited for further processing, e.g. to flours or starches. Processors thus need to choose their raw materials wisely dependent on the aimed product characteristics. However, the spectroscopic methods applied in the study were shown to be effective in assessing important quality attributes during cooking of the roots.

Retention of iron and zinc in yam flour and boiled yam processed from white yam (D. rotundata) varieties.

This study investigated the impact of processing on retention of iron and zinc in D. rotundata. Fresh tubers were processed into boiled yam and yam flour and analyzed for zinc, iron, and physicochemical properties. Percent true retention (%TR) was assessed using paired samples and a formula that compensated for loss or gain of moisture and soluble solids. The retention of iron ranged from 55.5% to 98.7% in boiled yam and 25.2% to 54.9% in yam flour; retention of zinc ranged from 49.3% to 97.5% in boiled yam and 18. 9% to 43.1% in yam flour. The amount of iron retained in boiled yam correlated with the amount in the fresh samples (r = .79), likewise in yam flour (r = .82). A similar trend was observed for zinc. From our study, we conclude that retention of iron and zinc is dependent on the variety and processing method used. The information from this study can be used by food scientists and nutritionists in choosing the appropriate processing to increase the retention of high levels of micronutrient in yams and by the yam breeders to adjust their germplasm breeding activities.