Ecological determinants of mould growth in stored grain

Grain entering store carries a microflora of 'field' and 'storage' fungi. Field fungi require readily available water and therefore seldom develop in store. By contrast, storage fungi, especially Aspergillus spp., are able to grow at low water activities (aw, 0.70-0.75) enabling them to initiate grain spoilage. The ability of storage fungi to germinate, grow and sporulate in stored grain is dependent on the availability of water in the substrate, temperature and the intergranular gas composition. These factors may interact to have a profound influence on the initiation of spoilage of stored grain by fungi. An understanding of the ecological determinants of mould growth may help to develop improved and safer methods of grain storage.