Research On Shelling And Peeling Process And The Key Technology Of Fresh Lotus Seed

With the improvement of people’s living standard, eating fresh lotus seed become more and more popular because of its high nutritional value and delicious taste. Lotus seed need to be shelling and peeling before further processing, but it is very hard to orientation because of its small size, and the membrane is very thin and close to the kernel. Thus cause the hard of shelling and peeling lotus seed. So the processing technology lag behind seriously hindered the development of lotus seed industry.Aiming at the difficult situation of fresh lotus seed shelling and peeling processing, this project researched the basic physical properties, shear properties and compression characteristic of fresh lotus seed. On the base of these research, effect of the key technological parameter and critical shelling component on the missing cut rate, damage rate, separation rate and peeling rate will be studied.The result of physical properties measurement shows that the mean diameter and maximum length of fresh lotus seed are more disperse than dry lotus seed. As the diameter become bigger, the length of lotus seed become longer and the shape of lotus seed become close to the sphere. The average thickness of shell is about0.724mm, which can be the basis of design cutting knife. The density of kernel is greater than shell, but there density is less than water.The result of mechanical property shows that fresh lotus have the characteristics of the elastomer before broken. The level of fresh lotus did not significantly affect shearing and compression rupture force and deformation. In order to ensure that lotus shell can be cut and lotus kernel can’t be crushed, the best compression deformation of fresh lotus seed is2mm-3mm. Moisture content had a significant influence on shearing and compression rupture force and deformation, and all showed a negative correlation. The storage time of fresh lotus, which under the condition of natural ventilation, have a significant influence on shearing and compression deformation and there was a positive correlation between them. Knife angle have a significant influence on shear rupture force and deformation, and showed a negative correlation; the shear rupture force is up to a maximum of50.1N when the knife angle is90°, and a minimum of14.6N when the knife angle is60°.The result of cutting experiment shows that different grade of lotus need different cutting space. The height of knife have a significant influence on cutting result, and the best cutting result occurs when the knife height is0.8mm. The orientation method and structure parameter have been tested though orientation test. The separation experiment shows that the width, height and travel distance of separation part all have a significant influence on separation rate. The optimal parameter have been achieved though orthogonal test, which is width10mm, height4mm and travel distance300mm. Under this condition, the separation rate can reach to82%.The results of peeling experiment research indicate that the solution temperature, soaking time and solution concentration all have a significant effect on the peeling rate. The optimal combination of the three factors was determined by orthogonal test, which wear solution temperature50℃, soaking time15min and solution concentration15g/L. Under such condition, the peeling rate can reach93.3%.