American Journal of Food Science and Technology
ISSN (Print): 2333-4827 ISSN (Online): 2333-4835 Website: Editor-in-chief: Hyo Choi
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American Journal of Food Science and Technology. 2016, 4(3), 58-63
DOI: 10.12691/ajfst-4-3-1
Open AccessArticle

Adoptive Trials on the Yam Pounding Machine for Cowpea Dehulling

Sanni L. A.1, Ogunsina B. S.1, , Adegbenjo A. O.2 and Ajayi M. O.1

1Department of Agricultural and Environmental Engineering, Obafemi Awolowo University, Nigeria

2Department of Bioresource Engineering, McGill University Montréal, Quebec, Canada

Pub. Date: April 18, 2016

Cite this paper:
Sanni L. A., Ogunsina B. S., Adegbenjo A. O. and Ajayi M. O.. Adoptive Trials on the Yam Pounding Machine for Cowpea Dehulling. American Journal of Food Science and Technology. 2016; 4(3):58-63. doi: 10.12691/ajfst-4-3-1


The yam pounding machine developed by Makanjuola (1975) was adopted for dehulling steeped cowpea grains. The machine simulates traditional method of dehulling steeped cowpea grains which involves rubbing the steeped grains between two abrasive surfaces until the seed coat becomes loose and gets detached from the endosperm. The main components include the dehulling chamber, the lid, beaters (inclined or vertical) and spline coupling. Performance evaluation of the machine was carried out considering three local varieties of cowpea (red drum, white drum and Ife brown), three steeping time (3, 5 and 10 mins) and two beater orientation (inclined and vertical). The results show that ‘Ife brown’ for which coefficients of dehulling and yield were 0.9902 and 0.9727, respectively indicated the highest dehulling efficiency (96.3%). With the inclined beaters, the coefficient of dehulling increased as steeping time increased; whereas, a decreasing trend was observed for other performance indices. With the vertical beaters, coefficient of dehulling and dehulling efficiency increased as steeping time increased; whereas, coefficient of wholeness decreased as steeping time increased. For the three varieties of cowpea, coefficients of dehulling and yield increased with steeping time; while a decrease was observed for coefficient of wholeness as steeping time increased. A machine of this nature is a significant development over existing methods of dehulling cowpea and will minimize the drudgery associated with small scale dehulling of cowpea. In addition, it presents opportunities for the manufacture of a dual purpose kitchen appliance with accessories suitable for yam pounding and cowpea dehulling.

adoption yam pounding machine cowpea dehulling performance evaluation

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