Effect of Processing on Some Physicochemical and Antinutritional Factors of Taro (Colocasia Esculenta (L.) Schott.) Grown in, Ethiopia
No Thumbnail Available
Date
2009-06
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Addis Ababa University
Abstract
Two cultivars of taro (Boloso I and Acc.236000) which were grown in Wollaita zone of Sothern Nations, Nationalities and People Ethiopia were analyzed for their proximate composition,
mineral composition, functional properties, and physicochemical properties and antinutritional factors composition. The effects of processing on these parameters were also determined. It was found that the range of values for raw sample; moisture content 0.54-0.92%, protein 5.83-9.14%, fat 0.35-1.05%, fiber 2.2-3.38%, total ash 4.46-5.44%, utilizable carbohydrate 82.88-8565% and Gross Energy 370.5-375.1Kcal/100 g. From minerals studied; Fe, 5.86-6.08 mg/100g (db), Zn,
43.08-48 mg/100g (db), Mg, 7.24-7.32mg/100g. Among the functional properties, water and oil absorption capacity ranged from 1.85-3.82 and 0.9-1.63 ml/g, respectively; bulk density 0.69- 0.88 g/ml, emulsion capacity10.6-35.6ml/g, emulsion stability 7.4-12.9 ml/g and foaming capacity 7.4-12.9 ml/g. Values for some physicochemical properties include ; pH4.92-6.44, TTA 0.32-1.71%,. The range of values for the antinutritional factors for raw sample Phytate 117.4- 135.3mg/100g, Oxalate, 243-265.9mg/100g, Tannin,47.69-59.92mg/100g, and Cyanide was not
detected in any of the cultivars studied. There was significance difference (p < 0.05) in the proximate composition between the two cultivars, antinutritional factors, some functional properties. Processing methods significantly affected the proximate composition of both cultivars. Boiling decreased the protein content of taro by 1.00-9.37%, but fermentation increased the protein content by 8.46-16.50%. The highest reduction of phytate about 86.6% was seen due to fermentation process. Boiling of taro resulted in highest reduction of oxalate (73.4%). The result indicated that fermentation was effective in the reduction of phytates from taro whereas the traditional processing, boiling was effective in the reduction of oxalate. Therefore, from the present study it can be concluded that no processing method is equally effective in reducing the antinutritional factors. From the two cultivars used in the present study Acc.236000 was more affected by the processing method in terms of all parameters studied than Boloso I.Key words: colocasia esculenta, antinutrients, fermentation, boiling, oxalate
Description
Keywords
Colocasia Esculenta, Antinutrients, Fermentation, Boiling, Oxalate