29 research outputs found
Impact of Shadow Drying on Nutritive and Antioxidant Properties of Leafy Vegetables Consumed in Southern Côte D’Ivoire
The abundance of leafy vegetables during the rainy seasons and poor transport and storage systems lead to their post-harvest losses in dry seasons. Effective preservation and storage of these plants would not only reduce their post-harvest losses but make them available throughout the year. Therefore a study was conducted on shadow drying effect on the nutritive and antioxidant properties of five selected leafy vegetables consumed in Southern Côte d’Ivoire. Experiment was conducted as follow: portions of washed and drained fresh leafy vegetables (500 g) were spread on clean filter paper and kept in a well-ventilated room of the laboratory at 25°C for 5, 10 and 15 days. The results of the proximate composition after 15 days of drying were: moisture (14.16 – 20.51%), ash (8.30 -19.16%), crude fibres (11.43 – 21.27%), proteins (9.13 – 19.05%), lipids (3.29 – 7.97%) and carbohydrates (32.45 – 51.74%). The minerals concentration increased with respective values after 15 days of shadow drying: calcium (78.23-337.26 mg/100g), magnesium (70.41-208.46 mg/100g), phosphorus (50.73-184.81 mg/100 g), potassium (363.56-776.73 mg/100g), iron (12.14-63.57 mg/100g) and zinc (12.57-33.95 mg/100g). During shadow drying, vitamin C and carotenoids were subjected to losses estimated to 65.52 – 91.07% and 39.66 – 95.23%, respectively. Contrary to these losses, antioxidant activity increased and ranged from 66.10 to 74.33% after 15 days of shadow drying. All these results suggest that the considerable nutrient contents of shade dried leafy vegetables make them good source of food when supplemented with sources of vitamin C and carotenoids in order to meet the nutritional requirements of Ivorian population
Purification and biochemical properties of a new thermostable xylanase from symbiotic fungus, Termitomyces sp.
A xylanase was purified from symbotic fungus, Termitomyces sp. by chromatography on columns of DEAE-Sepharose, CM-Sepharose, gel filtration and Phenyl-Sepharose. The preparation was shown to be homogenous by polyacrylamide gel electrophoresis. The purified enzyme displayed two protein bands on SDS-polyacrylamide gel electrophoresis and its molecular mass was estimated to 80-87 kDa. The xylanase exhibited maximum activity at 65-70°C and at pH 5.6, but it retained more than 80% of its activity in the pH range 5.0-6.0. The enzyme was stable for a long time-period up to 50°C and for 1 h at 60°C. Although the xylanase had a lower carboxymethylcellulase activity, it lacked activity towards substituted xylan, xylobiose, inulin, starch, polygalacturonic acid or pNP glycosides. Kinetic parameters indicated higher efficiency in the hydrolysis of beechwood xylan and birchwood xylan. The xylanase activity was stimulated by K+, Mn2+ and dithiol-reducing agents and was sensitive to Cu2+, Fe2+, Zn2+ and detergent agents. The enzymatic activity was observed in presence of urea up to a 1% (w/v) concentration. The enzyme could also be used in the presence of organic solvents such as acetone or dioxane (5%, v/v) without loss of activity.Keywords: Xylanase, Thermostable Termitomyces sp., Macrotermes subhyalinus, Termitida
Quality protein maize (QPM) seeds grown in Côte d’Ivoire: A source of high value edible oil
The search for new sources of oil with improved properties has focused our attention on the characteristics of oils extracted from white and yellow quality protein maize (QPM) seeds, two hybrids of classic maize (Zea mays L.). Physicochemical parameters of extracted oils were respectively as follow: refractive index (1.47 ± 0.00), free fatty acids (FFA) (1.4 ± 0.00 %), peroxide value (2.00 ± 0.00 and 1.33 ± 0.60 meq O2/kg), iodine value (136.20 ± 1.22 and 137.60 ± 1.22 g I2/100 g), and saponification value (203.83 ± 1.62 and 205.70 ± 1.62 mg KOH/g). Biochemical and nutritive analysis have revealed the following assets: unsaponifiable matter (1.43 ± 0.21 and 1.70 ± 0.10%), phosphorus (0.10 ± 0.02 mg/g), carotenoids (0.86 ± 0.01 and 1.06 ± 0.01 mg/g), vitamin A (0.45 ± 0.01 and 0.63 ± 0.01 mg/g) and vitamin E (0.32 ± 0.01 and 0.39 ± 0.01 mg/g). White and yellow QPM oilseeds showed higher content of linoleic acid (~ 60.2 % of total fatty acids). All these interesting characteristics should arouse attention for the usage of white and yellow QPM oilseeds as alternative to traditional corn oil in food and pharmaceutical industries.Keywords: Zea mays, quality protein maize, seed oils characterization, vitamin E, linoleic acid.African Journal of Biotechnology Vol. 12(23), pp. 3710-371
PRODUCTION D’ATTIEKE (COUSCOUS A BASE DE MANIOC FERMENTE) DANS LA VILLE D’ABIDJAN
A socio-economic and technological survey was conducted encompassing producers of attieké (a fermented cassava couscous) in Abidjan in order to determinate difficulties for the promotion of this activity. It was found that small women's individual businesses, with low education level, decide on their activity according to their capacity and the socioeconomic environment. They are integrated in the family economy by both the production place, which is confused with the producer residence, that by the time sharing between productive activities and the family activities. The production is carried out traditionally in arduous conditions according to the traditional experience of the producer and not on a theoretical and rational knowledge. Three types of attiéké (garba, agbodjama, normal) occurred whose the most met nationally is the normal type, which is an acid food, relatively poor in protein, high moisture content over than 45% and with an absence of Salmonella, which can ensure consumer safety. Professionalization and training of producers, establishment of good practice guides, labeling and standardization, are among other proposals to promote this activity
ISOTHERME D’ADSORPTION D’EAU DES FEVES DE CACAO (THEOBROMA CACAO L.) MARCHAND
This study presents the water adsorption isotherms of fermented cocoa beans obtained by drying natural sun. They were determined at 20, 30 and 40 ° C by the static gravimetric method. Equilibrium is obtained after 33 days for the final point. Mathematical models commonly used in the literature to describe the food products have helped explain the hygroscopic behavior during conservation. The regression analysis was performed under the Excel 2013 software, using the non-linear solver GRG algorithm in order to determine the coefficients models. The Guggenheim-Anderson-de Boer model (GAB) of three parameters showed good agreement with the experimental data (r = 0.995, 0.998 and 0.999 respectively for 20, 30 and 40 ° C). The water content of the monomolecular layer is 2.42 and 2.28% at 20 ° C, 2.19 and 2.12% at 30 ° C, 1.99 and 1.90% at 40 ° C for BET and GAB models, respectively. The isosteric heat of net adsorption tends to zero for higher water content (0.053 KJ / mol to 9.28% water). The linearity between enthalpy (net isosteric heat) and differential adsorption entropy shows them compensation
NOUVELLE TECHNIQUE DE TRANSFORMATION DE LA PULPE DE MANIOC (Manihot esculenta CRANTZ) SOUS FORME DE GRANULES CONSERVABLES SUR UNE LONGUE PERIODE
To solve the problem of conservation of fresh cassava, native cassava granules have been produced with three cultivars: bonoua, soglo and yacé. These granules made by drying the crushed, pressed and packaged in polyethylene bags 160 µm thick has been stored for two years at ambient temperature. The biochemical and microbiological analyses carried on the granules before and after preservation for two years have shown no significant change on the biochemical composition. These granules contain 10% humidity,84 % total carbohydrate, of which 55 % starch, 29 % total sugars including 20 % reducing sugars. These granules have been stable for the point of view of biochemical composition and the microbial content and did not contain cyanhydric acid. No browning reaction has been observed during preservation hence the granules have kept the colour of fresh cassav
Purification and characterization of three lowmolecular- weight acid phosphatases from peanut (Arachis hypogaea) seedlings
The maximum acid phosphatasic activity was detected in peanut seedlings the 5th day of germination. At least, three acid phosphatases were identified and purified by successive chromatography separations on DEAE-Sepharose CL-6B, CM Sepharose CL-6B, Sephacryl S-200 HR, and Phenyl- Sepharose HP to apparent homogeneity from developing five days old peanut seedlings. These enzymes designated acid phosphatase PI, PIIa and PIIb had native molecular weights of approximately 25.3, 22.4 and 24 kDa, respectively by gel permeation. SDS-PAGE of the purified acid phosphatase PI resolved two closely protein bands that migrated to approximately 14 and 12 kDa. Thus, this acid phosphatase likely functions as a heterodimer. Acid phosphatases PIIa and PIIb migrated as single band (each) with a similar molecular weight estimated to 21 kDa. The three enzymes had a similar optima pH (5.0) and temperature (55°C), and appeared to be stable in the presence of non-ionic detergents such as Triton X-100, Nonidet P 40 as well as Na+ and K+. Substrate specificity indicated that the three acid phosphatases hydrolyzed a broad range of phosphorylated substrates. However, natural substrates such as ADP and ATP were the compounds with highest rate of hydrolysis for acid phosphatase PI, while acid phosphatase PIIa exhibited phytasic activity. These results indicate that each purified acid phosphatase from peanut seedlings played a peculiar role during germination.Keywords: acid phosphatase; seedling; peanut; arachis hypogaea; germination; low-molecular-weigh
Physicochemical and biochemical characteristics evaluation of seven improve cassava (Manihot esculenta crantz) varieties of CĂ´te d'Ivoire
A lot of people around the world convert cassava roots into different products according to local customs and preferences. In Côte d’Ivoire, due to its high consumption, cassava is a subject of concern to researchers. For that purpose, seven improved varieties of cassava (with better productivity and resistance to many diseases), were set up by CNRA. Nevertheless, their valorization and popularization need information about physico-chemical, biochemical and sensorial characteristics. So, the aim of this study was to identify the best improved varieties regarding these characteristics. The physicochemical,'biochemical and sensorial characteristics were determined according to several standard methods and then the different data were submitted for statistical analyses. Three clusters of varieties were identified. The first cluster (C1) presented the highest energy value (170.26 Kcal/100 g), carbohydrate (37.65 g/100 g), starch (22.52 g/100 g), dry matter (40.79 g/100 g) and the lowest moisture (59.24 g/100 g) and reducing sugar (0.36 g/100 g). In opposition, the second cluster (C2) registered the lowest energy value (130.12 Kcal/100 g), carbohydrate (25.80 g/100 g), starch (6.12 g/100 g), dry matter (29.59g/100 g) while its moisture (70.41 g/100 g) and reducing sugar (0.91 g/100 g) where the highest. The third cluster (C3) presented values between those of cluster 1 and 2. Sensorial characteristics of all the cassava varieties were accepted. Varieties V4, V54 and V69 of the cluster C1, recorded the best characteristics.Key words: Valorization, popularization, cassava, characteristics, sensorial, original, cluster
Gender Consumption, Microbial Profile and Potential Risk of Hot Beverages of Coffee, Tea, Milk or Cocoa Sold by Street Vendors in Abidjan, Côte d’Ivoire
Street hot beverages are increasingly consumed in Côte d’Ivoire. However, there is little data on consumption and contaminants involved in the preparation of these beverages. Thus, this study aimed to contribute to the sanitary quality of hot beverages sold in street. The study assesses the motivation of hot beverages gender consumption and the profile of some contaminants of ready-to-drink hot beverages made of tea, coffee, milk or cocoa from street vendors. Hot beverage consumers were interviewed via a questionnaire and ready-to-drink hot beverages were collected and analyzed biochemically and microbiologically with conventional methods. Thus, 431 samples of these beverages were aseptically collected from five locations of Abidjan city. The survey was conducted among 1448 hot beverage consumers including 1149 males (80%) and 289 females (20%). The results showed that males (38.7%) consumed more coffee and females (45.7%) consumed more tea. Females (27.3%) consumed hot beverages for pleasure while males (27.4%) consumed them as stimulants. Hot beverages consumers reported symptoms of diarrhea, nausea, dizziness and hand tremors which could link to beverage consumption. The results of the investigation and the enumeration of microbial showed risks associated with the methods of preparing beverages with ingredients. Staphylococcus aureus, Bacillus cereus, Enterobacteria, yeasts and molds strains were enumerated from beverage samples. The tea with its ingredients (sugar, lemon or mint) were the most contaminated sample and coffee was least contaminated. The results of the survey showed a potential health risk linked to preparation methods, the type of beverages mainly tea with ingredients. Keywords: Street hot beverages, gender consumption, microbial contamination, sanitary quality DOI: 10.7176/FSQM/105-05 Received date: December 27, 2020 ; Revised date: January 31, 2021 ; Accepted date: February 27, 2021. Publication date: February 28, 2021