This work proposes to compare the extraction of total polyphenols and the coloring obtained after several series of decoction at 100°C/20min, of whole or crushed leaves of Combretum micranthum. The total phenolic...This work proposes to compare the extraction of total polyphenols and the coloring obtained after several series of decoction at 100°C/20min, of whole or crushed leaves of Combretum micranthum. The total phenolic content of the extracts obtained after decoction was determined by Folin’s method. The color parameters were measured using a colorimeter based on the CIELAB system. The analysis of variance (ANOVA) shows significant differences (p 0.05) on different parameters evaluated. The Minitab 19 software was used to classify the extracts according to the color parameters (L, A, and B). The results showed that the maximum of polyphenols (21.67%) was extracted in the crushed leaves after three series of decoctions while with the whole leaves the maximum of 16.17% is obtained after six series of decoctions. The concentration of total polyphenols becomes low from four series of decoctions with 0.146 g·AG·100 g<sup>-</sup><sup>1</sup> MS. The red and yellow coloring drops respectively by 85 and 69% with crushed leaves and 64 and 21% with whole leaves. The conductivity and the brix of the extracts fall according to the series of decoctions. These results show that for optimal use of C. micranthum leaves in traditional medicine, crushed leaves and three series of decoctions are indicated and sufficient.展开更多
The general objective of the work is to compare the effect of the addition of synthetic citric acid compared to the addition of natural fruit juice of Citrus aurantiifolia on the conservation of drink based on red cha...The general objective of the work is to compare the effect of the addition of synthetic citric acid compared to the addition of natural fruit juice of Citrus aurantiifolia on the conservation of drink based on red chalice H. sabdariffa. The tests were carried out over a period of 5 weeks at 4°C and 37°C with seven batches of beverage samples prepared at the rate of a calyx/water ratio of 1/40 (kg·kg<sup>-1</sup>) and added respectively citric acid at 1, 2 and 4 g·L<sup>-1</sup> and lemon juice at 10, 20 and 40 mL·L<sup>-1</sup>. The characterization of the different batches of beverages was carried out from day one. A follow-up of the residual anthocyanin content and the intensity of the red coloring were carried out over five weeks. The anthocyanin concentration was determined by the pH-differential method. The red color degradation index is determined based on the CIELAB color system (L*, a*, b* and L*). R and Minitab 18 software was used for data processing. The results of the monitoring of the parameters showed that the concentration of 1 g AC L<sup>-1</sup> retains 2.7 mg more of the anthocyanins than adding 10 mL JC L<sup>-1</sup> and longer maintains red color when stored at 4°C and 37°C/5 weeks. The 2 g AC L<sup>-1</sup> and 4 g AC L<sup>-1</sup> ratios have the same effects as the addition of 20 and 40 mL of lemon juice, all accelerating the degradation of anthocyanins and the red color. After 5 weeks of storage at 37°C, the effect of the temperature combined with the increase in the acidity of the samples (2 to 4 g AC L<sup>-1</sup> and 20 to 40 ml JC L<sup>-1</sup>), have accelerated the total disappearance of the red color on all samples.展开更多
Sodium bicarbonate is sometimes used to aid in the extraction of total polyphenols. Its main effect is to increase the pH of the extraction solution. Raising the pH can cause changes in the chemical structure of polyp...Sodium bicarbonate is sometimes used to aid in the extraction of total polyphenols. Its main effect is to increase the pH of the extraction solution. Raising the pH can cause changes in the chemical structure of polyphenols. This can lead to variations in their biological properties, solubility and stability. This work studied the effect of sodium carbonate on the extraction by aqueous decoction of total polyphenols from the leaves of Combretum micranthum. The content of total phenolic compounds in the extracts was estimated by the Folin-Ciocalteu method. The color of the samples was measured using a colorimeter (type: KONICA MINOLTA. Japan) based on the CIELAB color system. The results obtained were subjected to a one-way ANOVA analysis of variance with R software version 3.2.4 Revised (2018) and Minitab-18 software. The results reveal a drop in the concentration of extracted polyphenols proportional to the addition of sodium carbonate, i.e. a drop from 3.30 to 1.04 mg·AG·100 g<sup>-1</sup> of extract on whole leaves and 3.921 to 2.551 mg·AG·100 g<sup>-1</sup> extract on crushed leaves. On the other hand, the intensity of the coloring of the extracts increases significantly with the addition of sodium carbonate from 0.0 g·L <sup>-1</sup> to 0.666 g·L<sup>-1</sup>.展开更多
The baobab, Adansonia digitata L. plays an important role in the economy of local populations. The oil from the seeds of the baobab fruit is nowadays highly prized because of its numerous cosmetic and therapeutic appl...The baobab, Adansonia digitata L. plays an important role in the economy of local populations. The oil from the seeds of the baobab fruit is nowadays highly prized because of its numerous cosmetic and therapeutic applications and its composition of unsaturated fatty acids, sterols and tocopherols. However, unlike refined oils, locally extracted baobab oil has not undergone purification operations to ensure its quality. Only a filtration on special cloths is carried out after decantation. Indeed, the oil obtained after pressing is cloudy because of the presence of various impurities. It therefore requires treatment operations to make it more attractive and of higher quality. Therefore, in order to provide innovative solutions to local companies to improve the quality of vegetable oils, a study of clarification (treatment) of crude oil is necessary. An experimental device has been developed in the laboratory. It includes a glass column and a filter bed of dune sand and activated carbon. This study has shown the efficiency of the experimental device. Indeed, the activated carbon, thanks to its adsorbing power, has allowed a significant decrease in turbidity at the 5% threshold, from 14.61 NTU for the raw oil to 0.08 NTU for the oil filtered on 3% carbon and 0.033 NTU for the oil filtered on 5% carbon. That is to say an abatement higher than 95%. This decrease in turbidity could be correlated with the decrease in brown index from 187.39<sup>a</sup> for the initial crude oil to 128.53<sup>d</sup> for the oil treated with 3% activated carbon versus 187.59<sup>a</sup> for the oil filtered on cloths. The lowest brown index was observed with the filtration using 5% activated carbon (35.99<sup>b</sup>). Thus, for the yellowness index, only the filtration on 5% charcoal allowed to obtain a significant decrease in yellowness. The yellowing index of the oil with 5% was 44.67<sup>b</sup> against 79.04<sup>a</sup> for the oil filtered with 3% activated carbon, 86.33<sup>a</sup> for the crude oil and 86.46<sup>a</sup> for the oil filtered on cloths. Finally, the oil sample treated with 5% activated carbon had the clearest clarity than the other samples with a clarity (L) equal to 97.98<sup>c</sup> against 95.63<sup>d</sup> for the oil treated with 3% carbon and 94.99<sup>b</sup> for the oil filtered on filter cloths. According to the results obtained, the experimental device made it possible to obtain a clearer baobab oil with a low brown index, thus improving the sensory quality of the oil.展开更多
<em>Momordica charantia</em> is a plant species widely used in food and traditional medicine. However, the germination techniques and the performances of <em>M. charantia</em> are poorly unders...<em>Momordica charantia</em> is a plant species widely used in food and traditional medicine. However, the germination techniques and the performances of <em>M. charantia</em> are poorly understood by the populations. This study aims to better understand the germination, growth and development characteristics, and yield of <em>M. charantia</em>. Three pretreatments of the seeds are used for the shortening of the pre-germination period: soaking the seeds in tap water for 24 hours (batch 2), in hot water at 80<span style="white-space:nowrap;">˚</span>C (batch 3), for 24 hours and in the boiling water at 100<span style="white-space:nowrap;">˚</span>C for 24 hours (batch 4). A control without soaking (batch 1) was also carried out. The seeds were sown in plastic boxes in the laboratory with sterile sand and directly in the nursery in polyethylene sleeves. The influence of the light factor (light and dark) and watering frequency (every day and every two days) on the growth and yield parameters was evaluated respectively in the laboratory and in the nursery. Germination, growth and yield parameters were determined. The results show that the light and frequency of watering factors have no influence (p > 0.05) on the rate and duration of seed germination unlike pretreatments. Thus, Batch1 and 2 exhibit significantly higher germination rates (70% ± 16%) than Lots 3 and 4 (21% ± 15%) in the laboratory and in the nursery. On the other hand in terms of germination time, batch 3 and 4 displayed shorter durations (14 days) than those batch1 and 2 (23 days). Growth parameters and yield (fruit and seeds) are strongly influenced by watering frequency, unlike pretreatments which only affect yield. Growth and yield parameters are significantly higher with daily watering than daily watering. Ultimately, this study showed that pretreatments have an influence on the duration and rate of germination as well as the frequency of watering on the performance of <em>M. charantia</em>.展开更多
Tiger nut (Cyperus esculentus) is an underutilized tuber and a non-conventional oil seed which are known for their biological effect. The transformation of tubers into nutritional and stable flour could be important f...Tiger nut (Cyperus esculentus) is an underutilized tuber and a non-conventional oil seed which are known for their biological effect. The transformation of tubers into nutritional and stable flour could be important for West Africa populations. Thus, roasting is a process that improves the biochemical composition of seeds. The purpose of this study was to optimize temperature and roasting time on Tiger nut’s tubers in order to produce high nutritional tiger nut flour. A response surface methodology was used to optimize the roasting process in a temperature range (130°C - 150°C) and in a duration range (20 - 35 min). The data are processed by the software Statgraphic Centurion XVI version 16.2.04. Total polyphenols and flavonoids contents, antioxidant activity, titratable acidity, browning index and Maillard reaction products absorbance were evaluated. A second-order polynomial model was established to predict optimal values, included temperature and time. The contents of polyphenols and flavonoids range respectively from 0.196 to 0.891 g GAE/100g and from 0.022 to 0.051 g CE/100g, the antioxidant activity ranges from 25.21 to 57.09%, titratable acidity varies between 0.193 and 0.472 g/100g, the browning index from 28.42 to 56.20 and the absorbances at 420 nm of Maillard Reactions Products ranged between 0.365 and 0.897. The global desirability was 90%. Roasting had significant effects (p 0.05) on titratable acidity, browning index and antioxidant activity. The optimum roasting conditions were established at the temperature of 147°C for 38 minutes. Experimental values of parameter for flour obtained in optimal condition were proximate to predict values excepted titratable acidity. The model performance is acceptable for this study. The research for the optimal roasting conditions for tiger nut reveals an appropriate temperature and time combination which could improve the biochemical composition with a more attractive color.展开更多
Boumkaye is a traditional fermented millet-based drink (Pennisetum glaucum L.) produced in Casamance (region in Senegal). Unknown and circumcised beverage, it has therapeutic properties due to aqueous creeper extracts...Boumkaye is a traditional fermented millet-based drink (Pennisetum glaucum L.) produced in Casamance (region in Senegal). Unknown and circumcised beverage, it has therapeutic properties due to aqueous creeper extracts from Abrus pulchellus plant and naturally present during the process. The objective of this work was to investigate the fabrication process of a millet-based beverage as an alternative source of nutrients. The diagnosis of beverage production by monitoring its physical and chemical parameters during two months of storage at room temperature was studied. The established manufacturing process, composed by a production of aqueous extracts after maceration of the Abrus pulchellus vines, a preparation of millet slurry, and a fermentation step to obtain the Boumkaye, has several features. The study of aging process showed probable lactic and alcoholic fermentations. Further, the finished Boumkaye was characterized by a high acidity (pH of 3), an alcohol content of 5 g/100g and contains an appreciable amount of polyphenols (54.46 mg/100g).展开更多
Native of West Africa, Saba senegalensis belongs to the family of Apocynaceae, and is a wild plant that is mainly exploited in the diet. It grows mainly along riverbanks, in wooded savannah areas in humid areas, in ga...Native of West Africa, Saba senegalensis belongs to the family of Apocynaceae, and is a wild plant that is mainly exploited in the diet. It grows mainly along riverbanks, in wooded savannah areas in humid areas, in gallery forests and in rocky ravines and hills. Saba senegalensis is a large woody liana with white latex, dark gray bark, can reach more than 40 m high and a trunk that can measure up to 47 cm in diameter. The fruit is a globose shell, 7 to 10 cm long, 6 to 8 cm wide. The leaves are opposite, elliptical, dark green in color, about 8 to 15 cm long and 4 to 6 cm wide. This fruit is characterized by its richness in antioxidant molecules especially vitamin C (480 mg/100 g) and total polyphenols (945.83 mg/100 g). The fruit contents 41.43 until 80% water with a low pH (2.24). In Senegal, the fruit is eaten as it or transformed into puree, nectar, syrup, canned etc. It is a plant that has enormous therapeutic virtues, from the fruit to the roots through the leaves, bark, and latex. Despite its high nutritional potential, its many therapeutic virtues and its economic potential, Saba senegalensis remains under-exploited. Further researches on the nutritional and therapeutic properties deserve to be conducted.展开更多
Momordica charantia (Cucurbitaceae), is a plant commonly used in traditional medicine in Senegal whose fruits are weakly consumed by the population. However, no data exists on the nutritional intake of the latter. Thi...Momordica charantia (Cucurbitaceae), is a plant commonly used in traditional medicine in Senegal whose fruits are weakly consumed by the population. However, no data exists on the nutritional intake of the latter. This work aims to determine the physicochemical and biochemical characteristics of the pulp of Momordica charantia. The study focused on two lots of fruits from two geographically different regions of Senegal (Dakar and Fatick). The biochemical analyses of the pulp showed average values of protein from 2.39 ± 0.01 g/100 g to 3.19 ± 0.01 g/100 g;reducing sugar from 4.22 ± 0.10 g/100 g to 3.55 ± 0.10 g/100 g;totals sugar from 4.43 ± 0.02 g/100 g to 3.38 ± 0.58 g/100 g. The average contents of polyphenol and flavonoids were respectively from 1.91 ± 0.04 g/100 g to 1.04 ± 0.09 g/100 g and 32.59 ± 0.04 mg/100 g and 20.75 ± 1.19 mg/100 g. According to these results, the fruit of M. charantia may be considered as rich in antioxidant. At the opposite, it is very weak in mineral elements, such as calcium and potassium (1.01 mg/100 g;3.38 mg/100 g). Meanwhile, the seeds content 24% of lipids. Thus, investigations should be done on its biological proprieties, physical and biochemical components.展开更多
Mead is a beverage obtained by alcoholic fermentation of honey, with an ethanol content of 8% to 18% by volume. In Africa, mead manufacturing methods rely on heating honey and adding extracts of fruits, herbs or spice...Mead is a beverage obtained by alcoholic fermentation of honey, with an ethanol content of 8% to 18% by volume. In Africa, mead manufacturing methods rely on heating honey and adding extracts of fruits, herbs or spices. “Bessoudioury” mead is then prepared according to the traditional process of the Bassari and Bedick peoples of Kedougou (Senegal). This work on “Bessoudioury” aims to describe and characterize the manufacturing processes. It was also to evaluate the chemical and microbiological characteristics. The study focused on three Kedougou production sites. The manufacturing process of “Bessoudioury” includes a honey heating, a formulation step by adding wine of either Borassus aethiopicum Mart. or Elaeis guineensis. This step is followed by a fermentation’s one during two days. Wine is considered as the essential sources of yeasts for the production of alcohol. “Bessoudioury” has an ethanol content of 8% (v/v). Moulds and Streptococcus were not detected in this mead. According to its polyphenols content, this mead has a nutritional interest, but the process deserves to be reviewed to preserve nutrients.展开更多
This study deals with the valorization of natural residues into activated carbon prepared from waste“Baobab fruit shell”from the Fatick Region,Senegal.Thus,after the preparation of the baobab shell,a chemical activa...This study deals with the valorization of natural residues into activated carbon prepared from waste“Baobab fruit shell”from the Fatick Region,Senegal.Thus,after the preparation of the baobab shell,a chemical activation with orthophosphoric acid H3PO4(85%)was performed followed by pyrolysis at 530°C.To eliminate possible carbonization residues,the activated carbons were impregnated in 0.1 M hydrochloric acid and/or soda solutions and then washed thoroughly with distilled water to obtain a pH between 6.5 and 7.The latter were then dried in an oven at 105°C for 24 h.A characterization was carried out to determine the moisture content,the ash content,the iodine and methylene blue indices,the surface functions and the pH at zero charge point(pHpzc).The moisture and ash contents were 1.87%and 0.72%,respectively.The iodine and peroxide indices obtained were 939,09 mg/g and 575.73 mg/g,respectively.Surface function analysis by Boehm’s method showed that the acidic functions were higher than the basic functions and their pHpzc was lower than neutrality.The best efficiency of methylene blue removal was 99.75%and was obtained with a mass of 0.150 g of activated carbon,pH equal to 10,an initial concentration of methylene blue of 200 mg/L and a contact time of 35 min.展开更多
文摘This work proposes to compare the extraction of total polyphenols and the coloring obtained after several series of decoction at 100°C/20min, of whole or crushed leaves of Combretum micranthum. The total phenolic content of the extracts obtained after decoction was determined by Folin’s method. The color parameters were measured using a colorimeter based on the CIELAB system. The analysis of variance (ANOVA) shows significant differences (p 0.05) on different parameters evaluated. The Minitab 19 software was used to classify the extracts according to the color parameters (L, A, and B). The results showed that the maximum of polyphenols (21.67%) was extracted in the crushed leaves after three series of decoctions while with the whole leaves the maximum of 16.17% is obtained after six series of decoctions. The concentration of total polyphenols becomes low from four series of decoctions with 0.146 g·AG·100 g<sup>-</sup><sup>1</sup> MS. The red and yellow coloring drops respectively by 85 and 69% with crushed leaves and 64 and 21% with whole leaves. The conductivity and the brix of the extracts fall according to the series of decoctions. These results show that for optimal use of C. micranthum leaves in traditional medicine, crushed leaves and three series of decoctions are indicated and sufficient.
文摘The general objective of the work is to compare the effect of the addition of synthetic citric acid compared to the addition of natural fruit juice of Citrus aurantiifolia on the conservation of drink based on red chalice H. sabdariffa. The tests were carried out over a period of 5 weeks at 4°C and 37°C with seven batches of beverage samples prepared at the rate of a calyx/water ratio of 1/40 (kg·kg<sup>-1</sup>) and added respectively citric acid at 1, 2 and 4 g·L<sup>-1</sup> and lemon juice at 10, 20 and 40 mL·L<sup>-1</sup>. The characterization of the different batches of beverages was carried out from day one. A follow-up of the residual anthocyanin content and the intensity of the red coloring were carried out over five weeks. The anthocyanin concentration was determined by the pH-differential method. The red color degradation index is determined based on the CIELAB color system (L*, a*, b* and L*). R and Minitab 18 software was used for data processing. The results of the monitoring of the parameters showed that the concentration of 1 g AC L<sup>-1</sup> retains 2.7 mg more of the anthocyanins than adding 10 mL JC L<sup>-1</sup> and longer maintains red color when stored at 4°C and 37°C/5 weeks. The 2 g AC L<sup>-1</sup> and 4 g AC L<sup>-1</sup> ratios have the same effects as the addition of 20 and 40 mL of lemon juice, all accelerating the degradation of anthocyanins and the red color. After 5 weeks of storage at 37°C, the effect of the temperature combined with the increase in the acidity of the samples (2 to 4 g AC L<sup>-1</sup> and 20 to 40 ml JC L<sup>-1</sup>), have accelerated the total disappearance of the red color on all samples.
文摘Sodium bicarbonate is sometimes used to aid in the extraction of total polyphenols. Its main effect is to increase the pH of the extraction solution. Raising the pH can cause changes in the chemical structure of polyphenols. This can lead to variations in their biological properties, solubility and stability. This work studied the effect of sodium carbonate on the extraction by aqueous decoction of total polyphenols from the leaves of Combretum micranthum. The content of total phenolic compounds in the extracts was estimated by the Folin-Ciocalteu method. The color of the samples was measured using a colorimeter (type: KONICA MINOLTA. Japan) based on the CIELAB color system. The results obtained were subjected to a one-way ANOVA analysis of variance with R software version 3.2.4 Revised (2018) and Minitab-18 software. The results reveal a drop in the concentration of extracted polyphenols proportional to the addition of sodium carbonate, i.e. a drop from 3.30 to 1.04 mg·AG·100 g<sup>-1</sup> of extract on whole leaves and 3.921 to 2.551 mg·AG·100 g<sup>-1</sup> extract on crushed leaves. On the other hand, the intensity of the coloring of the extracts increases significantly with the addition of sodium carbonate from 0.0 g·L <sup>-1</sup> to 0.666 g·L<sup>-1</sup>.
文摘The baobab, Adansonia digitata L. plays an important role in the economy of local populations. The oil from the seeds of the baobab fruit is nowadays highly prized because of its numerous cosmetic and therapeutic applications and its composition of unsaturated fatty acids, sterols and tocopherols. However, unlike refined oils, locally extracted baobab oil has not undergone purification operations to ensure its quality. Only a filtration on special cloths is carried out after decantation. Indeed, the oil obtained after pressing is cloudy because of the presence of various impurities. It therefore requires treatment operations to make it more attractive and of higher quality. Therefore, in order to provide innovative solutions to local companies to improve the quality of vegetable oils, a study of clarification (treatment) of crude oil is necessary. An experimental device has been developed in the laboratory. It includes a glass column and a filter bed of dune sand and activated carbon. This study has shown the efficiency of the experimental device. Indeed, the activated carbon, thanks to its adsorbing power, has allowed a significant decrease in turbidity at the 5% threshold, from 14.61 NTU for the raw oil to 0.08 NTU for the oil filtered on 3% carbon and 0.033 NTU for the oil filtered on 5% carbon. That is to say an abatement higher than 95%. This decrease in turbidity could be correlated with the decrease in brown index from 187.39<sup>a</sup> for the initial crude oil to 128.53<sup>d</sup> for the oil treated with 3% activated carbon versus 187.59<sup>a</sup> for the oil filtered on cloths. The lowest brown index was observed with the filtration using 5% activated carbon (35.99<sup>b</sup>). Thus, for the yellowness index, only the filtration on 5% charcoal allowed to obtain a significant decrease in yellowness. The yellowing index of the oil with 5% was 44.67<sup>b</sup> against 79.04<sup>a</sup> for the oil filtered with 3% activated carbon, 86.33<sup>a</sup> for the crude oil and 86.46<sup>a</sup> for the oil filtered on cloths. Finally, the oil sample treated with 5% activated carbon had the clearest clarity than the other samples with a clarity (L) equal to 97.98<sup>c</sup> against 95.63<sup>d</sup> for the oil treated with 3% carbon and 94.99<sup>b</sup> for the oil filtered on filter cloths. According to the results obtained, the experimental device made it possible to obtain a clearer baobab oil with a low brown index, thus improving the sensory quality of the oil.
文摘<em>Momordica charantia</em> is a plant species widely used in food and traditional medicine. However, the germination techniques and the performances of <em>M. charantia</em> are poorly understood by the populations. This study aims to better understand the germination, growth and development characteristics, and yield of <em>M. charantia</em>. Three pretreatments of the seeds are used for the shortening of the pre-germination period: soaking the seeds in tap water for 24 hours (batch 2), in hot water at 80<span style="white-space:nowrap;">˚</span>C (batch 3), for 24 hours and in the boiling water at 100<span style="white-space:nowrap;">˚</span>C for 24 hours (batch 4). A control without soaking (batch 1) was also carried out. The seeds were sown in plastic boxes in the laboratory with sterile sand and directly in the nursery in polyethylene sleeves. The influence of the light factor (light and dark) and watering frequency (every day and every two days) on the growth and yield parameters was evaluated respectively in the laboratory and in the nursery. Germination, growth and yield parameters were determined. The results show that the light and frequency of watering factors have no influence (p > 0.05) on the rate and duration of seed germination unlike pretreatments. Thus, Batch1 and 2 exhibit significantly higher germination rates (70% ± 16%) than Lots 3 and 4 (21% ± 15%) in the laboratory and in the nursery. On the other hand in terms of germination time, batch 3 and 4 displayed shorter durations (14 days) than those batch1 and 2 (23 days). Growth parameters and yield (fruit and seeds) are strongly influenced by watering frequency, unlike pretreatments which only affect yield. Growth and yield parameters are significantly higher with daily watering than daily watering. Ultimately, this study showed that pretreatments have an influence on the duration and rate of germination as well as the frequency of watering on the performance of <em>M. charantia</em>.
文摘Tiger nut (Cyperus esculentus) is an underutilized tuber and a non-conventional oil seed which are known for their biological effect. The transformation of tubers into nutritional and stable flour could be important for West Africa populations. Thus, roasting is a process that improves the biochemical composition of seeds. The purpose of this study was to optimize temperature and roasting time on Tiger nut’s tubers in order to produce high nutritional tiger nut flour. A response surface methodology was used to optimize the roasting process in a temperature range (130°C - 150°C) and in a duration range (20 - 35 min). The data are processed by the software Statgraphic Centurion XVI version 16.2.04. Total polyphenols and flavonoids contents, antioxidant activity, titratable acidity, browning index and Maillard reaction products absorbance were evaluated. A second-order polynomial model was established to predict optimal values, included temperature and time. The contents of polyphenols and flavonoids range respectively from 0.196 to 0.891 g GAE/100g and from 0.022 to 0.051 g CE/100g, the antioxidant activity ranges from 25.21 to 57.09%, titratable acidity varies between 0.193 and 0.472 g/100g, the browning index from 28.42 to 56.20 and the absorbances at 420 nm of Maillard Reactions Products ranged between 0.365 and 0.897. The global desirability was 90%. Roasting had significant effects (p 0.05) on titratable acidity, browning index and antioxidant activity. The optimum roasting conditions were established at the temperature of 147°C for 38 minutes. Experimental values of parameter for flour obtained in optimal condition were proximate to predict values excepted titratable acidity. The model performance is acceptable for this study. The research for the optimal roasting conditions for tiger nut reveals an appropriate temperature and time combination which could improve the biochemical composition with a more attractive color.
文摘Boumkaye is a traditional fermented millet-based drink (Pennisetum glaucum L.) produced in Casamance (region in Senegal). Unknown and circumcised beverage, it has therapeutic properties due to aqueous creeper extracts from Abrus pulchellus plant and naturally present during the process. The objective of this work was to investigate the fabrication process of a millet-based beverage as an alternative source of nutrients. The diagnosis of beverage production by monitoring its physical and chemical parameters during two months of storage at room temperature was studied. The established manufacturing process, composed by a production of aqueous extracts after maceration of the Abrus pulchellus vines, a preparation of millet slurry, and a fermentation step to obtain the Boumkaye, has several features. The study of aging process showed probable lactic and alcoholic fermentations. Further, the finished Boumkaye was characterized by a high acidity (pH of 3), an alcohol content of 5 g/100g and contains an appreciable amount of polyphenols (54.46 mg/100g).
文摘Native of West Africa, Saba senegalensis belongs to the family of Apocynaceae, and is a wild plant that is mainly exploited in the diet. It grows mainly along riverbanks, in wooded savannah areas in humid areas, in gallery forests and in rocky ravines and hills. Saba senegalensis is a large woody liana with white latex, dark gray bark, can reach more than 40 m high and a trunk that can measure up to 47 cm in diameter. The fruit is a globose shell, 7 to 10 cm long, 6 to 8 cm wide. The leaves are opposite, elliptical, dark green in color, about 8 to 15 cm long and 4 to 6 cm wide. This fruit is characterized by its richness in antioxidant molecules especially vitamin C (480 mg/100 g) and total polyphenols (945.83 mg/100 g). The fruit contents 41.43 until 80% water with a low pH (2.24). In Senegal, the fruit is eaten as it or transformed into puree, nectar, syrup, canned etc. It is a plant that has enormous therapeutic virtues, from the fruit to the roots through the leaves, bark, and latex. Despite its high nutritional potential, its many therapeutic virtues and its economic potential, Saba senegalensis remains under-exploited. Further researches on the nutritional and therapeutic properties deserve to be conducted.
文摘Momordica charantia (Cucurbitaceae), is a plant commonly used in traditional medicine in Senegal whose fruits are weakly consumed by the population. However, no data exists on the nutritional intake of the latter. This work aims to determine the physicochemical and biochemical characteristics of the pulp of Momordica charantia. The study focused on two lots of fruits from two geographically different regions of Senegal (Dakar and Fatick). The biochemical analyses of the pulp showed average values of protein from 2.39 ± 0.01 g/100 g to 3.19 ± 0.01 g/100 g;reducing sugar from 4.22 ± 0.10 g/100 g to 3.55 ± 0.10 g/100 g;totals sugar from 4.43 ± 0.02 g/100 g to 3.38 ± 0.58 g/100 g. The average contents of polyphenol and flavonoids were respectively from 1.91 ± 0.04 g/100 g to 1.04 ± 0.09 g/100 g and 32.59 ± 0.04 mg/100 g and 20.75 ± 1.19 mg/100 g. According to these results, the fruit of M. charantia may be considered as rich in antioxidant. At the opposite, it is very weak in mineral elements, such as calcium and potassium (1.01 mg/100 g;3.38 mg/100 g). Meanwhile, the seeds content 24% of lipids. Thus, investigations should be done on its biological proprieties, physical and biochemical components.
文摘Mead is a beverage obtained by alcoholic fermentation of honey, with an ethanol content of 8% to 18% by volume. In Africa, mead manufacturing methods rely on heating honey and adding extracts of fruits, herbs or spices. “Bessoudioury” mead is then prepared according to the traditional process of the Bassari and Bedick peoples of Kedougou (Senegal). This work on “Bessoudioury” aims to describe and characterize the manufacturing processes. It was also to evaluate the chemical and microbiological characteristics. The study focused on three Kedougou production sites. The manufacturing process of “Bessoudioury” includes a honey heating, a formulation step by adding wine of either Borassus aethiopicum Mart. or Elaeis guineensis. This step is followed by a fermentation’s one during two days. Wine is considered as the essential sources of yeasts for the production of alcohol. “Bessoudioury” has an ethanol content of 8% (v/v). Moulds and Streptococcus were not detected in this mead. According to its polyphenols content, this mead has a nutritional interest, but the process deserves to be reviewed to preserve nutrients.
文摘This study deals with the valorization of natural residues into activated carbon prepared from waste“Baobab fruit shell”from the Fatick Region,Senegal.Thus,after the preparation of the baobab shell,a chemical activation with orthophosphoric acid H3PO4(85%)was performed followed by pyrolysis at 530°C.To eliminate possible carbonization residues,the activated carbons were impregnated in 0.1 M hydrochloric acid and/or soda solutions and then washed thoroughly with distilled water to obtain a pH between 6.5 and 7.The latter were then dried in an oven at 105°C for 24 h.A characterization was carried out to determine the moisture content,the ash content,the iodine and methylene blue indices,the surface functions and the pH at zero charge point(pHpzc).The moisture and ash contents were 1.87%and 0.72%,respectively.The iodine and peroxide indices obtained were 939,09 mg/g and 575.73 mg/g,respectively.Surface function analysis by Boehm’s method showed that the acidic functions were higher than the basic functions and their pHpzc was lower than neutrality.The best efficiency of methylene blue removal was 99.75%and was obtained with a mass of 0.150 g of activated carbon,pH equal to 10,an initial concentration of methylene blue of 200 mg/L and a contact time of 35 min.
