a. Harvesting: - There is an optimum time for harvesting cereals, depending on the maturity of the crop and the climatic conditions. This has a significant effect on the quality of the grain during storage. 

Harvesting often begins before the grain is ripe and continues until mould and insect damage are prevalent. Grain not fully ripened contains a higher proportion of moisture and will deteriorate more quickly than mature grains because the enzyme systems are still active. 

Cereals are traditionally harvested manually. There are three main types of harvesting equipment for the small scale producer: manual, animal powered and engine powered. Harvested crops are left in the field for a few days to dry before further processing. 

b. Threshing: - Threshing is the removal of grains from the rest of the plant. It involves three different operations: Separating the grain from the panicle; sorting the grain from the straw; winnowing the chaff from the grain. 

Separation of the grain from the panicle is the most energy-demanding of the three processes. It is the first process to have been mechanized. Sorting the grain from the straw is relatively easy, but is difficult to mechanise. Winnowing is relatively easy, both by hand and by machine. 

A range of engine powered threshers are available. 

c. Winnowing: - Winnowing is the separation of the grains from the chaff or straw. It is traditionally carried out by lifting and tossing the threshed material so that the lighter chaff and straw get blown to one side while the heavier seeds fall down vertically. 

Hand-held winnowing baskets are used to shake the seeds to separate out the dirt and chaff. They are very effective, but slow. 

There is a range of winnowing machines that use a fan to create artificial wind. This speeds up the winnowing process. 

Some of these contain sieves and screens that grade the grains as well. 

d. Drying: - Prior to storage or further processing, cereal grains need to be dried. The most cost-effective method is to spread out in the sun to dry. In humid climates it may be necessary to use an artificial dryer. 

Cereal grains should be dried to 10-15% moisture before storage.