Sanitation and Post-harvest Management Practices in Grain Traders’ Stores and the Impact on Grain Quality in Nairobi, Machakos and Embu Counties in Kenya

Abstract

In Kenya, similar to other economically developing nations, losses after harvest occur during storage mainly due to spillages, aflatoxin and damages due to improper handling. This study was undertaken to determine grain traders’ operations after harvest and the effect of sanitation procedures on quality of grains. In addition, ascertain qualitative and quantitative losses and how these losses affect the quality of grains in the market. In 2018, a cross-sectional survey was conducted in Nairobi, Embu and Machakos counties. Purposive sampling was used to select 20 grain traders per county who were stocking both maize and beans. One kilogram of maize and one for bean grain samples were bought for analysis of moisture content, losses in mass, nutritional content and total aflatoxins. The common grains in the store within the three counties were maize (98.4%) and beans (94.3%) followed closely by green grams (88.2%) and cowpeas (72.1%). Groundnuts and Dolichos beans were the least common grains in the traders stores at <15% overall. In the three counties, over 60% of grain sellers had knowledge about grain quality standards. However, majority of the traders exceeding 96% used own standards to grade the grains based on physical damage, color and grain size. Proportion of foreign matter and shriveled grains present in maize grain sample from Machakos was significantly (p<0.05) higher compared to that of the maize from Embu. No differences in proportion of foreign matter were observed between the maize from Embu and that of Nairobi. In beans, the number of total defective grains from the samples collected were significantly (p<0.05) higher in Machakos compared to those in samples collected in Nairobi and Embu. The incidence of grain contamination was highest in Machakos at 30% followed by Embu and Nairobi at 14% and 6%, respectively. Machakos had the highest contamination with levels of aflatoxin in maize grain with the highest record at 170ppb. In Embu County, the highest level was 140ppb while in Nairobi the highest recorded level of contamination was at 59ppb. For all, this is above World Health Organization recommended maximum limit of 20ppb. Sanitation practices should be encouraged in grain stores to minimize grain infestation by insects, rodents and mycotoxin contamination. This will improve durability of stored grains and conserve grain status in storage. Improved understanding of the connection linking sanitation and pest management is fundamental and may assist pest control professionals in putting together recommendations that promote adoption of sanitation by individuals in their storage facilities.