paddy cleaner is an important operation and highly recommended not only on a large and medium commercial scale, but also on a small scale. It consists of the separation of undesirable material, such as weed seeds, straw, chaff, panicle stems, empty grains, inmate and damaged grains, sand, rocks, stone, dust, plastic and even metal and glass particles. The degree of cleanness of the paddy reflects to some extent the care applied during harvesting, threshing and handling.
A hand operated paddy winnower was developed by Central Rice Research Institute, Cuttack. The winnower was ergonomically evaluated using 12 subjects. Two women workers are required for the operation of this winnower, one for cranking the blower and other for feeding the threshed material and collection of grain.
The mean heart rate of the women workers and their output were measured to evaluate the winnower. The mean heart rate of women workers during operation was found to be 112 beats/min. The energy expenditure rate in operation of the equipment was 10.7 kJ/min. The average output was found to be 242 kg grain/h and winnowing efficiency was found to be 88.36%. The equipment developed was found to be suitable for operation by women workers as the heart rate, work pulse value and energy expenditure rate are within the acceptable limits.
If insects are present in the stored grain, proper identification is important, as some are internal feeders while others are external feeders. Internal feeders cause damage to the grain by rice destoner, while external feeders feed on grain dusts, cracked kernels, or other grain debris. Some of the most destructive stored grain pests include the granary weevil (aka wheat weevil), maize weevil, and rice weevil. Purdue University Extension constructed a key for the stored grain beetles that may be found in a bin. In addition to beetles, the larvae of the Indian meal moth can also cause damage to stored grain.