postthreshing

Postthreshing refers to the series of post-harvest operations that follow threshing, the process of separating grain from the straw. The goal is to produce clean, uniform grain at safe moisture levels for storage, milling, or sale. Postthreshing handling minimizes losses from broken kernels, chaff, and impurities and reduces the risk of spoilage.

Common postthreshing steps include cleaning and removal of chaff and weed seeds using screens, aspirators, and gravity separators; drying to safe moisture levels using sun or mechanical dryers; and grading to separate kernels by size or weight. These steps improve milling performance, quality, and market value.

Equipment ranges from simple hand tools and winnowing baskets to multi-stage seed-cleaning machines. In small operations, manual winnowing and sieving may suffice; larger facilities employ gravity separators, air-screen cleaners, and optical sorters to handle bulk grains.

Storage considerations are central to postthreshing. Grains are kept dry and protected from pests, with moisture content stabilized typically around 12 percent for many cereals. Proper storage includes sanitation, aeration or hermetic sealing, and regular monitoring for spoilage, sprouting, or insect damage.

Postthreshing losses can occur through bruising, cracking, or shattering, and through moisture uptake or infestation. Effective postthreshing practices aim to minimize these losses and maintain grain quality from harvest to processing.