Senior Lecturer, Dr.S.B.Navarathne, has been granted the patent for his invention of the ” Counter Current-Repulsive De-corticator” to remove seed coat of sesame. Dr,Navarathne is attached to the Department of Food Science and Technology of the Faculty of Applied Sciences.
This innovation is based on the working principle of motor and pestle. When motor is moving manually in an up and down motion vertically, seed coats of water soaked sesame seeds tend to detach from the cotyledons due to friction between seed coat and pestle as well as seed coat & motor. Thus, the working principle of motor and pestle has been mechanized by horizontally rotating axle. The axle is equipped with couples of pushing devices, which were welded in a manner in order to create counter current water flows towards the each other. A devices similar to the pestle (However it is in minute scale) has been welded to the points of the axle, where counter current motions are met. When the axle of the device is rotating at the seed of 500 – 550 RPM, pushing devices create counter current water gushes along with wet sesame seeds.
When wet sesame seeds are coming from opposition directions as high energy streams and colliding at a point where miniaturized pestle is situated. Thus, the wet sesame seeds in turbulent flows are subjected to collide with each other as well as with the little pestle. Due to repulsive motions of water flows, an adequate friction is being developed between seeds and seeds as well as seeds and metallic surface of the pestles. Hence, formed friction is capable to detach seed coat from the cotyledons. Capacity of this prototype designed is about 50kg per hour and capable to remove more than 99% of the seed coat of sesame without disturbing to its physical and chemical properties.