Mechanization of Membrane Removing for Lotus Seeds

• Main Authors: Wen-Luh Huang, 黃文祿
• Other Authors: 盛中德
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/72007169898117495008

博士 === 中興大學 === 生物產業機電工程學系所 === 99 === A water jet was applied to break and remove the membranes of fresh lotus seeds. In Chinese cuisine, the membrane of the fresh lotus seed has to be removed. Due to the membrane to be very thin, traditional hand removal is a time-consuming and tedious work. For developing a membrane remover of lotus seed, lotus seed membrane thickness and other features are important. Experiment results showed that lotus seed membranes are 0.023-0.133 mm thick and symmetrical, and the thickest membrane at the apical point. This study performed lotus seed rolling and fixation tests using three types of spray nozzles. With the water jet pressure as the major impact factor, this study showed a flat spray nozzle with high water pressure to be more powerful for removing lotus seed membranes. Membrane removing mechanisms can be divided into the following stages：membrane breakage, continuous membrane removal, and the removal of the apical point membrane. The lotus seed removal machinery includes multiple spray nozzles which are aligned in a line and an additional lever conveyor, which would make the continuous removal operation of lotus seed membranes to be continous. By the machine development process, such as designing, manufacturing, testing machine and revising, a water jet membrane remover for lotus seeds was completed. The water jet membrane remover consists of the following parts: a set of rubber rollers, feeding and control device, a lever conveyer and a water power system water jet module with five sprayer nozzles. The principle of membrane removed is to use the friction force from two rubber rollers with the same rotation direction and different speeds. The developed of membrane remover has been tested in order to analysis its performance. The results show that the membrane removing rate is affected by the speeds of the rollers, level conveyor and applied water pressure. The membrane removing speed does have a relatively low influence on the elliptical and round lotus seeds. The lower speed of lever conveyor and higher pressure of water jet have the higher membrane removing rate. As to damaging rate, the rollers with lower rotational speed will have higher damaging rate. The speed of level conveyer and pressure of water jet are the more influent factor to membrane removing rate. The various membrane removing operating factors are tested and analysed. The results show as the rollers speed of 18 rpm, the lever speed of 2.5 cm/s and the water jet pressure of 6.5kg/cm2 the membrane removing rate to be 82.67％ for the elliptical seed. As the rollers speed of 50 rpm, the lever speed of 2.5 cm/s and the water jet pressure of 6.5kg/cm2 the membrane removing rate is 85.33％. These removing rates are acceptable for practical operation.