Читать книгу Dry Beans and Pulses Production, Processing, and Nutrition онлайн

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Dry beans are commonly stored in a wide variety of structures constructed as wood cribs, concrete silos, or steel bins. These vary based on the availability of existing infrastructure and general market conditions. Concrete silos have been noted for their capacity, structural strength, and general mass. These facilities resist rapid temperature change, which impacts the internal temperature of both the beans and the interspatial air. Storage facilities, particularly in northern latitudes, are exposed to the heat of the southern sun, and such surface heating will cause differential temperature changes within the stored beans and result in moisture migration and localized regions of high moisture spoilage. Concrete has been demonstrated to resist this temperature gradient better than other materials (Roberston and Frazier 1978; Maraveas 2020).

Economical flat‐storage, in which beans are piled on a reinforced concrete floor, has gained popularity due to the availability of free‐span pole building construction, rapid and flexible filling with adequate control of seed coat checking and splitting, and a high capacity to cost benefit ratio. It is noted that this technique requires beans of stable moisture content, and full knowledge of the angle of repose (which is the naturally self‐aligning angle that the bean pile assumes). Exceeding this angle will result in lateral pressure and cause cascading avalanches that can readily damage or destroy the side walls of the facility (Uebersax and Siddiq 2012).