∑ Accordingto the percentage of the air in the grain,it is possible to calculate
the weightof the seedsthat can be storedin 1 m^3. For example, for wheat
about700 kg/m^3 , and for flour500 kg/m^3.
∑ In the intergranular space,air currents (àconvection currents)can move
fromone placeto the otherand carrywatervapour.
∑ The intergranularspacefacilitatesfumigationtreatmentsfor insectcontrol.
∑ By changingthe concentration of the atmosphericgasesin the intergranular
air it is possible to control or depress insectsand fungal development.
Watervapour
The watervapouris located in the intergranular air. If thereis a temperature
gradientin the commodity, the watervapouris carriedfromthe hot to the cold
Fig. 26.1 The grainbulkas an ecosystem.Improvingthe control of insects in foodprocessing 409