Mwaisenye, N.J. (presumably March 2019): Micronutrient composition of selected sun-dried and cooked indigenous vegetables: A case of Chinoje and Mzula villages, Dodoma, Tanzania.

Master Theses

Indigenous leafy vegetables are very important in human diet as they supply a number of important nutrients. Consumption of indigenous leafy vegetables are associated with reduced risk of non-communicable diseases such as high blood pressure, diabetes mellitus and certain types of cancer. However leafy vegetables are seasonal and highly perishable characterized with abundance shortly after the rainy season but become scarce during the dry season. The cross-sectional study was carried out at Mzula and Chinoje villages in rural Dodoma. A total of randomly selected 120 participants were interviewed using a pretested and structured questionnaire. For laboratory analysis, three mostly common consumed varieties of indigenous leafy vegetables were selected; Fwene (Amaranthus hybridus), Mlenda (Corchorus olitorius) and Mgange (Cleome gynadra) from each village. Six samples from the selected varieties of indigenous leafy vegetables analyzed when were fresh, Six samples analyzed after cooked when fresh and six samples analyzed after cooked when dried. Drying and cooking activities were done at respective villages and laboratory analysis was conducted at the Department of Food Technology, Nutrition and Consumer Studies of SUA, Morogoro. One kilogram each of selected indigenous leafy vegetables were washed and cut into thin slices and spread on mats of sacks on a floor for drying for 9 hrs daily for three days at 30-32oC and Relative humidity, 80-85%. Two hundred and fifty grams of fresh and sun-dried Mlenda (C. olitorius) was separately pound in a mortar. 250g of fresh and dry samples, were cooked for 5 minutes. Fresh samples were washed and collected in freezer bags for laboratory analysis and cooked samples were packed in a cooling box for laboratory analysis. Samples wrapped in an Aluminum foil to prevent detrimental effect of sunlight to vitamins. The data analyzed were β-carotene, vitamin C, minerals (iron, calcium and zinc). Data were entered and processed using Excel and SPSS software version 20.0. Two-Way ANOVA analysis and results expressed as means ± standard deviation. A cooking method shown significantly (p<0.05) to lower β-carotene and vitamin C than sun-drying process and also sun-drying and cooking had significant (p<0.05) reduction of the mineral contents of the selected vegetables. At (p<0.05), a dried Mgange (C. gynadra) from Chinoje has also shown to have the highest β-carotene content, Fwene (dried) (A. hybridus) from Mzula village has shown to have the highest amount of vitamin C. A cooked Mlenda (C. olitorius) from Chinoje has shown to have lowest level of vitamin C. Mlenda (dried) (C. olitorius) have shown to have significantly (p<0.05) highest concentration of Zinc and Calcium from Chinoje and Mzula respectively. A cooked Mgange (C. gynadra) from Chinoje had the lowest level of zinc and iron concentrations. Generally, proper processing methods is important for maximum nutrient retention of indigenous leafy vegetables.

Scale-N is financed by BMEL
Scale-N Zalf