Design And Fabrication Of Yam Pounding Machine
Introduction Yam is another crop cultivated across Nigeria. It is a seasonal crop and very difficult to preserve as it tends to rot. Nearly all Nigerians consume yam on a regular basis and in large quantities particularly the Yoruba tribe in Nigeria. Nature allows yam to form a bond when it is pounded or beaten in a mortar, it is then consumed as a meal with a choice soup. Pounded yam is a staple food consumed by the indigenous process of pounding yam is very laborious. It requires physical pounding by one or more people. Depending on the quantity in the mortar, in a bid to reduce the labour involved in yam pounding came the manufacturing of Herbert mixer, the Kenwood mixer and Hammermill in early 1975. These intended yam pounders failed due to some limitations in their operational functions. The Herbert and Kenwood mixers had almost the same operational principle and they had been identified for poor pounding due to the flapping (moving up and down) of their stirrer or mixer which is keyed to the electric rotating shaft. In addition to the poor pounding of both pounders, the Herbert mixer was found to heat excessively and as a result, the machine has to be stopped intermittently for cooling purposes. 1.1 Historical Background Yam belongs to the class of carbohydrate type of food and had been one of the oldest recipes known to man. It has been a major food crop in many of the African/Caribbean countries such as Ghana, Ethiopia, Benin Republic and Nigeria in particular. Also, in some other parts of the world like Brazil, India, Oceania and Latin America, yam is a major source of food. The word “yam” was derived from the Wolof word “nyam” which is a Portuguese name meaning “to taste”. Also, in other African languages, it can mean “to eat” e.g. in Hausa “nyam”. This perennial herbaceous crop is of different species such as white yam (Dioscorea-rotundata)