Browsing by Author "Matemu, Athanasia"

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African nightshades (Solanum nigrum complex): The potential contribution to human nutrition and livelihoods in sub-Saharan Africa.
(John Wiley & Sons, Inc., 2021-05-03) Sangija, Frank; Martin, Haikael; Matemu, Athanasia
Achieving zero hunger in sub-Saharan Africa (SSA) without minimizing postharvest losses of agricultural products is impossible. Therefore, a holistic approach is vital to end hunger, simultaneously improving food security, diversity, and livelihoods. This review focuses on the African nightshades (ANS) Solanum spp. contribution to improving food and nutrition security in SSA. Different parts of ANS are utilized as food and medicine; however, pests and diseases hinder ANS utilization. African nightshade is rich in micronutrients such as β-carotene, vitamins C and E, minerals (iron, calcium, and zinc), and dietary fiber. The leaves contain a high amount of nutrients than the berries. Proper utilization of ANS can contribute to ending hidden hunger, mainly in children and pregnant women. Literature shows that ANS contains antinutritional factors such as oxalate, phytate, nitrate, and alkaloids; however, their quantities are low to cause potential health effects. Several improved varieties with high yields, rich in nutrients, and low alkaloids have been developed in SSA. Various processing and preservation techniques such as cooking, drying, and fermentation are feasible techniques for value addition on ANS in SSA; moreover, most societies are yet to adopt them effectively. Furthermore, promoting value addition and commercialization of ANS is of importance and can create more jobs. Therefore, this review provides an overview of ANS production and challenges that hinder their utilization, possible solutions, and future research suggestions. This review concludes that ANS is an essential nutritious leafy vegetable for improving nutrition and livelihoods in SSA.
Agro-Morphological Exploration of Some Unexplored Wild Vigna Legumes for Domestication
(MDPI, 2020-01-13) Harouna, Difo Voukang; Venkataramana, Pavithravani; Matemu, Athanasia; Ndakidemi, Patrick
The domestication of novel or hitherto wild food crops is quickly becoming one of the most popular approaches in tackling the challenges associated with sustainable food crop production, especially in this era, where producing more food with fewer resources is the need of the hour. The crop breeding community is not yet completely unanimous regarding the importance of crop neo-domestication. However, exploring the unexplored, refining unrefined traits, cultivating the uncultivated, and popularizing the unpopular remain the most adequate steps proposed by most researchers to achieve the domestication of the undomesticated for food and nutrition security. Therefore, in the same line of thought, this paper explores the agro-morphological characteristics of some wild Vigna legumes from an inquisitive perspective to contribute to their domestication. One hundred and sixty accessions of wild Vigna legumes, obtained from gene banks, were planted, following the augmented block design layout of two agro-ecological zones of Tanzania, during the 2018 and 2019 main cropping seasons for agro-morphological investigations. The generalized linear model procedure (GLM PROC), two-way analysis of variance (two-way ANOVA), agglomerative hierarchical clustering (AHC) and principal component analysis (PCA) were used to analyze the accession, block and block vs. accession effects, as well as the accession × site and accession × season interaction grouping variations among accessions. The results showed that the wild species (Vigna racemosa; Vigna ambacensis; Vigna reticulata; and Vigna vexillata) present a considerable variety of qualitative traits that singularly exist in the three studied checks (cowpea, rice bean, and a landrace of Vigna vexillata). Of the 15 examined quantitative traits, only the days to flowering, pods per plant, hundred seed weight and yield were affected by the growing environment (accession × site effect), while only the number of flowers per raceme and the pods per plant were affected by the cropping season (accession × season effect). All the quantitative traits showed significant differences among accessions for each site and each season. The same result was observed among the checks, except for the seed size trait. The study finally revealed three groups, in a cluster analysis and 59.61% of the best variations among the traits and accessions in PCA. Indications as to the candidate accessions favorable for domestication were also revealed. Such key preliminary information could be of the utmost importance for the domestication, breeding, and improvement of these species, since it also determines their future existence—that is, so long as biodiversity conservation continues to be a challenging concern for humanity
Antibacterial and antifungal activities of selected wild mushrooms from Southern Highlands of Tanzania
(American Journal of Research Communication, 2014) Chelela, Baraka; Chacha, Musa; Matemu, Athanasia
The antibacterial and antifungal activities of crude extracts of Lactarius sp, Russula kivuensis, Amanita muscaria, Amanita phalloides, Lactarius gymnocarpoides and Lactarius densifolius (wild mushrooms) were evaluated against. The results showed that, A. muscaria petroleum ether extract (MS1PE) exhibited moderate antimicrobial activity against Shigella flexneri and Klebsiella oxytoca with MIC of 1.56 mg/mL. Chloroform (MS1C), petroleum ether (MS1PE) and ethanol (MS1E) extracts of A. muscaria showed weak activity against Vibrio cholera and Streptococcus pyogens (3.13 mg/mL). Mycobacteria were more resistant to all wild mushroom extracts. On the other hand, A. muscaria ethanol extract (MS1E) showed high activity against Candida albicans with MIC of 0.78 mg/mL moreover, it was least active against Cryptococcus neoformans (MIC = 12.5 mg/mL). The A. muscaria chloroform extract (MS1C) showed moderate activity against both C. albicans and C. neoformans (MIC = 1.56 mg/mL) while its petroleum ether extract (MS1PE) was weakly active against both C. albicans and C. neoformans (MIC of 6.25 mg/mL). The crude extracts of wild mushroom species tested showed inhibitory activity against some bacteria and fungi species giving insight into development of antimicrobial agent and its application in pharmacological activities.
Assessment of Water Absorption Capacity and Cooking Time of Wild Under-Exploited Vigna Species towards their Domestication
(MDPI, 2019-09-04) Harouna, Difo Voukang; Venkataramana, Pavithravani; Matemu, Athanasia; Ndakidemi, Patrick
Some phenotypic traits from wild legumes are relatively less examined and exploited towards their domestication and improvement. Cooking time for instance, is one of the most central factors that direct a consumer’s choice for a food legume. However, such characters, together with seed water absorption capacity are less examined by scientists, especially in wild legumes. Therefore, this study explores the cooking time and the water absorption capacity upon soaking on 84 accessions of wild Vigna legumes and establishes a relationship between their cooking time and water absorbed during soaking for the very first time. The accessions were grown in two agro-ecological zones and used in this study. The Mattson cooker apparatus was used to determine the cooking time of each accession and 24 h soaking was performed to evaluate water absorbed by each accession. The two-way analysis of variance revealed that there is no interaction between the water absorption capacity and cooking time of the wild Vigna accessions with their locations or growing environments. The study revealed that there is no environment × genotype interaction with respect to cooking time and water absorption capacity as phenotypic traits while genotype interactions were noted for both traits within location studied. Furthermore, 11 wild genotypes of Vigna accessions showed no interaction between the cooking time and the water absorption capacity when tested. However, a strong negative correlation was observed in some of the wild Vigna species which present phenotypic similarities and clusters with domesticated varieties. The study could also help to speculate on some candidates for domestication among the wild Vigna species. Such key preliminary information could be of vital consideration in breeding, improvement, and domestication of wild Vigna legumes to make them useful for human benefit as far as cooking time is concerned.
Chapter 8 - Current trends and opportunities of plant-based non-alcoholic probiotic beverages: A European and African perspective
(Elsevier, 2021-05) Mandha, Juliana; Shumoy, Habtu; Matemu, Athanasia; Raes, Katleen
Although dairy-based foods have been the main probiotic food sources, a range of plant-based products are currently being developed to meet the needs of vegetarians, lactose intolerant persons, individuals on low cholesterol diets or allergic to milk proteins. This chapter reviews the plant based non-alcoholic probiotic beverages in Europe and Africa. It begins with an introduction of regulations that govern the production, safety and marketing of probiotic beverages in Europe and Africa, followed by a discussion of the commercial, traditional, and experimental studies of plant-based non-alcoholic beverages, categorized as cereals, vegetable/legume, and fruit-based probiotic beverages.
Characterization of fruit juices and effect of pasteurization and storage conditions on their microbial, physicochemical, and nutritional quality
(Elsevier Ltd., 2023-02) Mandha, Juliana; Shumoy, Habtu; Matemu, Athanasia; Raes, Katleen
Characterization, pasteurization and storage are essential steps in fruit juice processing. Watermelon, pineapple, and mango juices were pasteurized at 80 ± 2 °C and held at different treatment times (1, 2.5, 5, 10, and 15 min). Juice yield, pH, proximate composition, total soluble solids, color, vitamin C, microbial quality, mineral content, enzyme activity (polyphenol oxidase (PPO), and peroxidase (POD)), total phenolic content, and antioxidant capacity were measured during pasteurization and cold storage (4 °C). Results showed that watermelon juice had the highest crude protein, pH, and moisture content, pineapple juice had the highest titratable acidity, vitamin C and mineral content (potassium, calcium, magnesium, manganese, and zinc) and mango juice had the highest juice yield, and total soluble solids. Regardless of the holding time, pasteurization reduced total plate counts and yeast and molds to below detectable limits (1 log CFU/mL). Vitamin C was undetectable in watermelon juice after 10 min of pasteurization compared to mango juice with a 27% reduction. Pasteurization preserved mango juice color, but watermelon juice became less red and more yellow with increasing treatment time. POD was more thermoresistant than PPO and needed a treatment time of at least 5 min to obtain 80% reduction. Storage of more than 9 days negatively affected the watermelon color, total phenolic content and antioxidant capacities of watermelon juice pasteurized at 15 min and vitamin C content of unpasteurized mango juice. Thus, pasteurization and storage affect fruit juice quality depending on the type of fruit and their composition.
Chemical composition of ethanolic extracts of some wild mushrooms from Tanzania and their medicinal potentials
(Begell House Inc., 2016) Chelela, Baraka; Chacha, Musa; Matemu, Athanasia
The ethanolic extracts of 5 edible and inedible wild mushrooms collected from the Southern Highlands of Tanzania were characterized by gas chromatography–mass spectrometry. A total of 75 chemical compounds were obtained, mainly fatty acids, carotenoids, alkaloids, phenols, terpernes, steroids, pyranoside, saccharides, and amino acids. Chemical compounds were identified from the ethanolic extract of Russula cellulata, R. kivuensis, Lactarius densifolius, L. gymnocarpoides, and Lactarius sp. In addition, mass spectra of 4 major groups of compounds were also determined. This study confirms the presence of some important bioactive compounds, such as essential fatty acids (oleic and linoleic), amino acids, and carotenoids. The reported chemical profiles give an insight into the use of wild mushrooms as a potential source of bioactive compounds for nutraceuticals and pharmaceuticals.
Contribution of the Dolichos Lablab value chain to farmer's household livelihood assets in Tanzania
(Elsevier Inc., 2022-11-17) Minde, Josephine; Matemu, Athanasia; Venkataramana, Pavithravani
Lablab is a legume with multiple uses as food, feed, and organic fertilizer. However, it is underutilized, and its empirical contribution to farmers' livelihoods is limited. This study examined the Lablab value chain (LVC) relative to smallholder farmers' livelihood assets in Tanzania. Data on Lablab farming, its value chain, and its contribution to the farmers’ livelihood assets were collected from four districts of Tanzania known for Lablab production. The results showed that the LVC mapping comprised systems, actors, and interdependent activities, the key systems being input supply, tillage, intercropping, and marketing. Seed supply was through the recycling of the last harvest (48.8%), while intercropping (56.5%) and hand-hoeing (51.6%) were the primary cultivation systems, with farm gates and/or local markets serving as the marketing locations. The grown seeds were mainly black (62.3%) due to external marketability but were rarely eaten. Although farmers were the major chain actors, traders were highly active in the marketing segment, leaving farmers out of the bargain art protocol. Generally, Lablab production generated almost 90% of the farmers' revenue by multiple linear regression. Based on farmers' five asset categories, natural and human assets contributed 70% and 50% respectively, while there was less contribution from social, financial, and physical assets. The study recommends networking exposure to reliable marketplaces with good prices, improved seed availability, and financial services for Lablab farmers in Tanzania. To sustain the smallholder farmers' five livelihood assets from Lablab, researchers and policymakers must pay attention to the three linkages of the LVC.
Cytotoxicity activity of some wild mushroom species from Southern Highlands of Tanzania
(American Journal of Research Communication, 2014) Chelela, Baraka; Chacha, Musa; Matemu, Athanasia
The crude extracts from six wild mushroom species (Russula cellulata, Afrocantharellussymoensis, Lactarius sp, Lactarius denigricans, Russula kivuensis, Amanita muscaria and Amanita phalloides) collected from the Southern Highlands of Tanzania were evaluated for cytotoxicity effects against Brine shrimp (Artemia salina) nauplii. The lethal concentration which kills 50% of the larva, LC50 (μg/mL) of the wild mushroom extracts was evaluated. The results showed that, A. muscaria ethanol (MS1E) and petroleum ether (MS1PE) extracts exhibited highest cytotoxicity activity with LC50 of 11.00 and 13.72 μg/mL respectively. Lactarius. denigricans ethanol extract (BM10E) also possessed highest cytotoxicity activity with LC50 of 12.77 μg/mL as compared to its petroleum ether extract (BM10PE) with LC50 of 18.96 μg/mL, followed by chloroform (BM10C) and acetone (BM10A) extracts with LC50 of 32.56 μg/mL and 47.79 μg/mL respectively. In contrast, petroleum ether extract of A. symoensis (BM6PE) showed non-toxic effect on Brine shrimp larvae with LC50 of 202.96 μg/mL. The study on cytotoxicity effect of wild mushrooms will give an insight into possibility of isolating stronger anticancer agents.
Dietary Practices, Nutrient Adequacy, and Nutrition Status among Adolescents in Boarding High Schools in the Kilimanjaro Region, Tanzania.
(Hindawi, 2020-07-01) Nicholaus, Calista; Martin, Haikael; Kassim, Neema; Matemu, Athanasia; Kimiywe, Judith
A cross-sectional study was conducted to assess dietary practices, nutrient adequacy, and nutrition status among 164 adolescents aged between 16 and 19 years in boarding secondary schools in the Kilimanjaro region. In-depth interviews and a survey guided by a semistructured and structured questionnaire, including 24-hour recall and food frequency questionnaire techniques, were used to collect information. Nutrition status was assessed using anthropometric measurements and hemoglobin levels. WHO AnthroPlus software and NutriSurvey software were used to analyze anthropometry and dietary data, respectively. Diet in boarding schools was monotonous comprising mainly of cereal-legume meal with low intake of animal sources, fruits, and vegetables. Mean intake of energy, vitamin C, iron, calcium, and zinc was 1392 kcal, 24.8 mg, 9.2 mg, 134.5 mg, and 4.3 mg, respectively, which were below the Recommended Daily Allowance. The average carbohydrate, fat, and protein intake of 471.9 g, 73.7 g, and 80.7 g, respectively, were slightly higher than the Recommended Daily Allowance in both sexes. Male had a significantly higher intake of protein and carbohydrates ( < 0.001). Female had a significantly ( < 0.001) high intake of fat compared to male adolescents. Overall, 23.1% of the adolescents were anaemic, 25% were overweight, and 6.1% were obese. Boarding secondary schools' diet is monotonous and are inadequate in key micronutrients, iron, zinc, calcium, and vitamin C. There is a coexistence of undernutrition and overnutrition among adolescents in boarding schools. Therefore, monitoring adolescents' dietary intake and nutrition status is a key in preventing adolescents' malnutrition in the short term and diet-related diseases in the long term.
Distribution and occurrence of indigenous strains of atoxigenic and toxigenic Aspergillus section Flavi in groundnut producing areas of Southern Tanzania
(Journal of Biodiversity and Environmental Sciences (JBES), 2019-04-28) Mfaume, Juma; Matemu, Athanasia; Mbega, Ernest
The objective of this study was to isolate and identify atoxigenic and toxigenic strains of Aspergillus section Flavi in southern Tanzania, and investigate possible application of atoxigenic strains in control of aflatoxin levels in groundnuts. Fungal communities in soils from groundnut fields were examined to see the distributions of aflatoxin-producing Aspergillus species and to spot endemic atoxigenic strains. Forty-five isolates belonging to Aspergillus section Flavi were collected randomly from soils of groundnut fields in three districts and characterized using morphological and physiological examination. Aspergillus section Flavi was detected in 40/45 (88.89%) of the soil samples collected in Mtwara, Tanzania. Members of Aspergillus section Flavi L-strain was the most common (79.5%), followed by S-strains (18.4%) and finally Aspergillus tamarii (1.8%). The mean colony forming unit (CFU) of the Aspergillus colonies per gram of soil was highly variable (p < 0.05) among the districts, ranging from 8.5×102 to 8.2×103 . The mean pH across the gathering sites additionally varied (pH 5.5- 6.8) which is within the optimal pH requirement for the members of Aspergillus section Flavi. Non-significant (p > 0.05) variation in temperature across the sampling sites was observed. The results also showed that Aspergillus flavus was detected in all the three districts. Atoxigenic strains have a potential value to be employed as biological control agents to mitigate aflatoxin in groundnuts.
Does Pesticide exposure contribute to the growing burden of non - communicable diseases in Tanzania
(Elsevier B.V., 2022-09) Martin, Haikael; Matemu, Athanasia; Kassim, Neema; Kimiywe, Judith; Nicholaus, Calista
Pesticide exposure is becoming a public health concern in Tanzania. This review highlights the existing information on pesticide exposure, health effects, knowledge, and awareness on pesticide handling and management and in the current pesticide regulations in Tanza- nia. There was a significant increase in pesticides importation of up to 4.5 million liters’ in 2017 and registration of 1,114 pesticides in 2018. Food, water and soil are subjected to unacceptable levels of pesticide residues. Inadequate awareness of the effects of pes- ticides among the population of Tanzania was observed. Even though there are existing regulations governing pesticides, the inadequate management of pesticide in Tanzania was identified to contribute the malpractices in pesticide usage. Persistence of the malpractice in pesticide handling has been observed which argues for immediate intervention. Limited information concerning pesticide poisoning and adverse health effects has been reported but the magnitude of the health effects is not well known. There is scarce data on the association between pesticide and non-communicable diseases (NCDs) in Tanzania. This review is informative to the policy, practices, and intervention towards the existing situa- tion of pesticide in Tanzania. In addition, it calls for further investigation of the absence of data on pesticide exposure and NCDs
Dolichos Lablab-an underutilized crop with future potentials for food and nutrition security: a review.
(Taylor & Francis Online, 2020-06-12) Minde, Josephine; Venkataramana, Pavithravani; Matemu, Athanasia
Achieving the Sustainable Development Goals (SDGs) particularly goal number two in developing countries by 2030 is challenging. The State of Food Security and Nutrition (2019) in the World show prevalence of undernourishment which has practically remained unchanged for the last three years. This calls for sustainable synergies between food and nutrition in addressing the challenge. Exploring the potential of underutilized legumes such as Dolichos Lablab () in improving food and nutrition security is of importance. Lablab is known among nutritious underutilized diversified legumes, which is drought tolerant relative to other legumes. However, it is less popular as human food. This review focuses on providing details on the nutritional potential of underutilized Lablab varieties for food availability, accessibility and satisfactorily utilization for improved livelihood. So far research attention has been focusing on good agronomic performance with less information on their nutritional quality and its contribution to the wellbeing of people. Both wild and cultivated Lablab accessions do differ morphologically and across diverse habitat environments. This may make them less known, untapped and underutilized despite its promising potential as a food resource in developing countries where malnutrition still exists. Efforts are needed to popularize high-quality nutritional accessions, enhancing their consumption and commercialization for feeding the ever-increasing population in the future.
Effect of drying methods on the nutritional and anti-nutritional quality of African nightshade (Solanum sp.)
(INNSPUB, 2022-08-25) Kazosi, Marynurce; Martin, Haikael; Matemu, Athanasia
African nightshade (ANS) is a luminary food plant, considered a cheap and potential dietary source for micronutrients and bioactive compounds. This study evaluated the effects of drying techniques on nutritional (minerals & vitamin C) and anti-nutritional (oxalates & phytate) contents of Solanum scabrum (SS) and S. villosum (SV). The study employed three methods of drying; indirect solar drying (ISD), mixed solar drying (MSD), and open sun drying (OSD). Furthermore, blanching (85 °C, 2 min) with and without 3% NaCl were used as pre-treatments. Results showed that the ISD method retained more vitamin C in a range of 14.76% - 19.2% in both SS and SV leaves. The ISD was the most effective method in Ca (92.90%, 96.57%), Fe (77.88%, 71.54%), and Zn (86.94%, 90.09%) retention for both SS and SV leaves, respectively. On the other hand, all drying methods significantly reduced the oxalate and phytate content. The effect of pre-treatment methods on nutrient retention and anti-nutrients remaoval was also recorded. Results showed that ISD to be the best method for vitamin C and minerals retention and anti-nutrient reduction. Therefore, ISD can be a suitable method for preserving ANS while retaining nutrients and reducing anti-nutrients.
Effect of lactic acid fermentation of watermelon juice on its sensory acceptability and volatile compounds
(Elsevier Ltd., 2021-10-01) Mandha, Juliana; Shumoy, Habtu; Devaere, Jolien; Schouteten, Joachim; Gellynck, Xavier; de Winne, Ann; Matemu, Athanasia; Raes, Katleen
Fermentation increases food shelf-life but is characterized by changes that affect product's perception. Watermelon juice was fermented with Lactobacillus plantarum (WJ-LP), L. rhamnosus (WJ-LR), L. casei (WJ-LC), L. brevis (WJ-LB) and Pediococcus pentosaceus (WJ-PP). Their sensory characteristics and volatile compounds were investigated by consumers and Headspace Solid Phase Microextraction integrated with Gas Chromatography-Mass Spectrometry, respectively. WJ-PP and WJ-LB were most liked and perceived with ‘watermelon-flavor’, ‘natural taste’, ‘sweet’ and ‘watermelon-color’ while WJ-LC, WJ-LP and WJ-LR were least liked and perceived as ‘sour’, ‘bitter’, ’off-flavor’, ‘aftertaste’ and ‘intense-flavor’. Fifty-four volatiles were identified. After fermentation, alcohols, ketones, monoterpenes, acids, and furans increased while aldehydes and alkanes decreased. Lactic acid fermentation introduced 4-decanone and 2,3-butanedione in WJ-LB, WJ-LC, WJ-LP and WJ-LR, however, heptanal, 2-heptenal, 2,6-nonadienal, 2-decenal, and 2,4-decadienal in WJ-LC, heptanal, 2-hexenal, 2-heptenal, 2,6-nonadienal, 2-decenal and octanal in WJ-LR and 2,6-dimethyl-2,6-octadiene in WJ-LP disappeared. Juice sensory profiles were associated with their volatile compounds.
Effect of lactic acid fermentation of watermelon juice on its sensory acceptability and volatile compounds.
(Elsevier Ltd., 2021-04-19) Mandha, Juliana; Shumoy, Habtu; Devaere, Jolien; Schouteten, Joachim J; Gellynck, Xavier; de Winne, Ann; Matemu, Athanasia; Raes, Katleen
Fermentation increases food shelf-life but is characterized by changes that affect product's perception. Watermelon juice was fermented with Lactobacillus plantarum (WJ-LP), L. rhamnosus (WJ-LR), L. casei (WJ-LC), L. brevis (WJ-LB) and Pediococcus pentosaceus (WJ-PP). Their sensory characteristics and volatile compounds were investigated by consumers and Headspace Solid Phase Microextraction integrated with Gas Chromatography-Mass Spectrometry, respectively. WJ-PP and WJ-LB were most liked and perceived with 'watermelon-flavor', 'natural taste', 'sweet' and 'watermelon-color' while WJ-LC, WJ-LP and WJ-LR were least liked and perceived as 'sour', 'bitter', 'off-flavor', 'aftertaste' and 'intense-flavor'. Fifty-four volatiles were identified. After fermentation, alcohols, ketones, monoterpenes, acids, and furans increased while aldehydes and alkanes decreased. Lactic acid fermentation introduced 4-decanone and 2,3-butanedione in WJ-LB, WJ-LC, WJ-LP and WJ-LR, however, heptanal, 2-heptenal, 2,6-nonadienal, 2-decenal, and 2,4-decadienal in WJ-LC, heptanal, 2-hexenal, 2-heptenal, 2,6-nonadienal, 2-decenal and octanal in WJ-LR and 2,6-dimethyl-2,6-octadiene in WJ-LP disappeared. Juice sensory profiles were associated with their volatile compounds.
Effect of lactic acid fermentation on the nutritional quality and consumer acceptability of African nightshade
(Wiley Online Library, 2022-04-26) Sangija, Frank; Martin, Haikael; Matemu, Athanasia
African nightshade (ANS) is among many underexploited and neglected indigenous vegetables. This study assessed the effect of lactic acid fermentation (LAF) on nutritional and sensory quality in Solanum villosum (Sv) and Solanum scabrum (Ss). Spontaneously fermented (SF) and controlled fermented (CF) conditions using Lactobacillus plantarum LP90 and Leuconostoc mesenteroides LM58 were employed for 15 days and 120 h. From the fermented pickles, relish products were prepared using cooking oil and a variety of spices. The relish products were subjected to a consumer acceptability test. Results show a significant drop in pH to <3.5, increasing titratable acidity (TTA) to around 0.6 after 120 h and 15 days of CF and SF, respectively. LAF resulted in a 2.6–5 and 1.6–4.8-fold significant rise in β-carotene in pickles and their relish products. All pickles and relish products exhibited a significant decrease (p < .05) in vitamin C by 88.33%–95.90%. LAF significantly reduced total phenolic (26%– 43%) and Chlorophyll (16.45%–39.25%). On the other hand, LAF showed improvement in minerals content (P, Ca, Fe, and Zn) and reduction of tannin (76.27%–92.88%) and oxalate (77.33%–90%) levels. LAF relish products were highly preferred by the consumers, with S. villosum controlled fermented relish (SvCFR) leading. All fermented relishes were stable at ambient (27°C) and refrigeration (4°C) temperatures after 6 months of storage. Generally, LAF is an effective method for ANS preservation, with improved nutritional quality and safety. LAF can therefore be recommended to small-scale farmers, processors, and households for ANS preservation. Ultimately, this method enhances the nutrition and sensory quality, safety, and livelihood.
Effect of Lactic Acid Fermentation on Volatile Compounds and Sensory Characteristics of Mango (Mangifera indica) Juices
(MDPI, 2022-01-28) Mandha, Juliana; Shumoy, Habtu; Devaere, Jolien; Schouteten, Joachim; Gellynck, Xavier; De Winne, Ann; Matemu, Athanasia; Raes, Katleen
Fermentation is a sustainable bio-preservation technique that can improve the organoleptic quality of fruit juices. Mango juices were fermented by monoculture strains of Lactiplantibacillus plantarum subsp. plantarum (MLP), Lacticaseibacillus rhamnosus (MLR), Lacticaseibacillus casei (MLC), Levilactobacillus brevis (MLB), and Pediococcus pentosaceus (MPP). Volatile compounds were sorbed using headspace solid phase microextraction, separated, and identified with gas chromatography mass spectrometry. Forty-four (44) volatile compounds were identified. The control, MPP, and MLB had higher amounts of ethyl acetate, ethyl butyrate, 2-hexenal, 2,6-nonadienal, 2,2-dimethylpropanal, β-selinene, γ-gurjunene, α-copaene, and δ-cadinene, while MLC, MLP, and MLR had higher amounts of 2,3-butanedione and a cyclic hydrocarbon derivate. Consumers (n = 80) assessed their overall liking and characterized sensory attributes (appearance, color, aroma, flavor, consistency, acidity, and sweetness) using check-all-that-apply, and penalty analysis (just-about-right). Overall liking was associated with ‘mango color’, ‘pulp’, ‘mango aroma’, ‘sweet’, ‘natural taste’, and ‘mango flavor’ that described the control, MLB, MLC and MPP. Juices MLR and MLP were described as ‘bitter’, ‘sour’, ‘aftertaste’, and ‘off-flavor’. Multivariate analysis revealed relationships between the volatile com pounds, mango juices fermented by different lactic acid bacteria, and sensory characteristics. Thus, the type of lactic acid bacteria strains determined the volatile and sensory profile of mango juices.
Effect of processing on nutritional and anti-nutritional composition of false sesame (Ceratotheca sesamoides) and common bean leaves (Phaseolus vulgaris)
(International Journal of Biosciences, 2019-08-19) Kandonga, Agness; Makule, Edna; Matemu, Athanasia
The effects of blanching and drying on micro-nutrients: β-Carotene, Vitamin C, Folic acid, Iron (Fe), Zinc (Zn), Phosphorus (P) and anti-nutrients: Tannins and Oxalates composition of False Sesame Leaves (FSL) and Common Bean Leaves (CBL) were investigated. Vegetables preferences and preservation technologies used were assessed using questionnaire. Micronutrients content: β-Carotene, Vitamin C, and folic acid were analyzed using HPLC method while Fe, Zn were determined using Atomic Absorption Spectrophotometer (AAS) and Phosphorus was determined using UV-VIS Spectrophotometer. The oxalate and tannin were determined by titration and Folin Ciocalteu method. Several vegetables were identified, FSL (95.9%) and CBL (100%) being one of them. In vegetable processing, boiling (76.9%) and sun drying (15%) were reported in Bahi and Mbeya Rural Districts respectively. Sun drying was the commonly used method in both districts. Folic acid and β- Carotene were not detected in both vegetables. The vitamin C content in fresh FSL and CBL was 16.28mg/100g and 5.48mg/ 100g, yet the content was significantly reduced (p<0.05) by blanching and sun drying. False sesame leaves contained P (700mg/kg), Fe (115.75 ± 2.23mg/kg) and Zn (14.13mg/kg) whereas in CBL P was 600mg/kg Fe (652.76mg/kg) and Zn (41.04 ± 0.28mg/kg) respectively. Levels of P, Fe and Zn were significantly (p<0.05) increased by sun drying respectively. On the other hand, tannin and oxalate content in blanched and sun dried leaves were lower than in fresh leaves. Sun drying of FSL and CBL while covering after blanching further reduces tannins and oxalates, thus it is recommended as an effective method in anti-nutrients elimination.
Evaluation of functional attributes and storage stability of novel juice blends from baobab, pineapple, and black-plum fruits
(Heliyon, 2022-04-27) Adedokun, Tawakalt; Matemu, Athanasia; Hoglinger, Otmar; Mlyuka, Erasto; Adedeji, Akinbode
Several under-utilized tropical fruits have exceptional micronutrients and phytochemical composition with the potential to contribute to the nutrition of people and also enhance food security. This study was carried out to evaluate the quality attributes and storage stability of juice blends of baobab (Adansonia digitata), pineapple (Ananas comosus), and black-plum (Syzygium cumini) fruits for use as functional beverages. Juice blends were analyzed for physicochemical, antioxidant, and sensory properties. Mineral compositions and storage stability of the pasteurized juice blends at 4 C for 4 weeks were also investigated. Results showed that the vitamin C contents of individual juices synergistically contributed to the high values observed in the blends (317.45–414.51 mg/L). Juice blends of baobab, pineapple, and black-plum fruits are good sources of calcium (57–153 mg/L), magnesium (71–130 mg/L) and antioxidants (ascorbic acid, total polyphenol contents (65–104 mg GAE/100 mL), scavenging ability (105.97–359.71 μmol TE/100 mL), and reducing potential (1376–1829 μMFe2þ L) the consumption of which will promote human health. Blending enhanced the sensory qualities of the individual juices with improved taste and consumer acceptability. The juice blends kept well for two weeks at 4 C though the color becomes less intense at the end of the storage period. These findings suggest that baobab-fruit pulp, pineapple, and black-plum fruits can be major ingredients in producing a consumer acceptable anti-oxidant rich functional beverage for optimal benefits to consumers.