EFFECT OF TRADITIONAL AND HERMETIC BAG STORAGE METHODS ON GRAIN QUALITY OF MAIZE (Zea mays L.): THE CASE OF WEST SHOA ZONE, BAKO, ETHIOPIA

Abstract

Maize is one of the most important staple foods and the basis of the diet for Ethiopian's. The present study was conducted to compare the effectiveness of traditional (Gombisa and Sack) and of hermetic bag storage methods concerning quantitative and qualitative losses after 2, 4 and 6 months of storage. Stored grains were sampled from upper, middle and lower parts of the storages using compartmentalized sampling spear. Collected samples were assessed for total insect number, insect mortality, moisture content, grain damage, weight loss and germination percentage. Moreover, the samples were also analyzed for grain quality deterioration over time. The grain temperature and relative humidity followed the pattern of the ambient temperature and was higher than the ambient temperature and relative humidity during entire storage periods. Moisture content, insect infestation, weight loss and damaged grains showed an increasing pattern with prolonged storage. The lowest grain temperature and moisture content were recorded in Hermetic bag, whereas the highest in Gombisa and Sack, respectively. The highest percentage of insect infestation was observed in grains stored in Gombisa whereas, maximum bulk density and germination percentage were recorded in grain samples taken from Hermetic bag. Fusurium incidence was 10.0% at initial and increased significantly to 45.0% in six months. The incidence of Aspergillus, and Penicillium was o% at initial and increased significantly to 33.3 and 22.4% in six months. Maximum incidence of Fusurium and Penicillium 29.9% and 15.7% was recorded in Gombisa. Among the storage types all the values of total protein, total fat and total ash were statistically different (P<0.05) from each other and the values showed reduction in all the three storages. Maximum (2.40%) ash content was obtained from Hermetic bag in the end of six months. Protein content was high 8.90% at initial period and dropped significantly to 6.2% in Gombisa, 7.30% in Sack and 7.4% in Hermetic bag at the end of the storage periods. It was concluded that the quality of maize grain stored in Gombisa and Sack storage methods was low. Therefore, these storages were inadequate for protecting stored maize from insect pests and fungal attacks. Overall, the hermetic bag storage can protecting insect infestation and fungal development and consequently maintains seed viability and nutritional content during storage without use of insecticides.