Moulds infesting local and imported rice (Oryza spp.) in Cameroon

Loss in quality and quantities of rice during storage is an important issue to focus on. Moulds contaminating rice were investigated and their injuries on rice during storage were evaluated. Local and imported rice samples sold in markets and mills were stored for 3 months under laboratory conditions. The contaminated grains were counted and analyzed to characterize storage moulds. All rice samples evaluated were contaminated by moulds, right from sampling date. The quantity of mouldy grains varied from 1.1% for the rice sample from UNVDA to 4.2% rice brand ‘Main dans la Main’. The highest mould infestation in terms of quality and quantity, was recorded on imported rice samples of world rice and ‘Main dans la Main’ 22.3 and 25.3% respectively; meanwhile ‘Tox 3145 parboiled’, Uncle Benz and Neima presented 7.5, 8.9 and8.9% respectively. In general, imported rice samples contained the highest fungal load with a proportion of 65.9% compared to 34.3% for local samples. Among the 67 isolated strains, the genus Aspergillus dominated, followed by Penicillium, Mucor and Circinella with 13.4, 8.9, and 4.4% respectively. Therefore in Cameroon, some locally produced, but mostly some imported rice contain moulds from different genera, which damage rice at different proportions. It is urgent to develop methods to inhibit the growth of potential storage moulds and preserve the quality of rice consumed.