Design and construction of a centrifugal egg breaking machine.

Abstract

An egg (ovum) is one of the world's most important and useful poultry products in East Africa since it's a source of food and income. Eggs are composed of three main parts: eggshell, egg white (albumen) and yolk, representing 9.5%, 63%, and 27.5%, respectively, of the whole egg. The major operations done on eggs during egg processing are mainly cleaning, breaking and separation of the required egg components. The main objective in egg processing is usually to extract the inside liquid components from the whole egg for the manufacture of various products such as bread, cakes etc. In Uganda today, egg breaking and separation by both large scale, medium scale and small-scale egg processors is mainly accomplished by the use of hand held knives method. This method leads to time wastage during the process, leading to delays in production due to long production time thus making the process hard due to the low capacity. It also leads to the escape of eggshell particles into the egg liquid, high risks of contamination by the workers, occupies a large production space since it requires a lot of individuals to work on large numbers of eggs in a given time thus high labor costs. Therefore, this project was carried-out to design and construct a centrifugal egg breaking machine which was constructed to resolve these problems faced by egg processors. The machine breaks the eggs, separates off the eggshells and finally allowing the egg liquid to flow into the collecting container by gravity without mixing the components. The NPV value obtained was positive hence the project is highly viable. The centrifugal egg breaking machine was constructed running at a capacity of 50 L/hr, with an egg liquid yield of 93.6%, extraction efficiency of 77.6% and an extraction loss of 5.3% compared to that of knife method of 31.7L/Hr capacity, 85.8% egg liquid yield, 74.9% extraction capacity and 12.9% extraction loss. In addition, a wooden stick rod was selected to overcome clogging in the auger pipe, as the eggshells tend to rotate about the center of rotation of the auger.