Study of Grain Storage in Plastic Bags Aimed at Small-scale Farmers.

Abstract

Grain storage performed by small farmers results in considerable losses, often reaching values above 30% in grain quantity and quality. One of the main problems small producers face is insect infestation that causes severe grain damage, at times leading to complete losses. Efficient and safe organic methods to control insects attacking stored grains are scare. Grain storage in plastic bags has been studied in large-scale productions, in which an atmosphere of high CO2 concentration and O2 reduction directly related to grain moisture develops inside the bag. In this atmosphere, greater grain moisture results in higher CO2 concentration. It should be noted that this system has not been tested for small-scale grain production, which is generally stored in small bags of about 60 kg or in 200-L drums. The aim of this work is to study storage of dry corn (Zea mays) grains (14% of moisture) in 40 kg hermetic plastic bags, a system that can be adapted to small producers. Bags were filled with dry corn grains; different proportions of moist corn grains were placed in screened plastic tubes of 100 mm in diameter, to generate a greater CO2 concentration inside the bag. Thus, a natural system of self-modified atmosphere is created, which is efficient in insect control and grain storage and poses no risk of damage or contamination. The results of the experiment showed that this is an efficient method for storing dry corn grains, which attains sound organic insect control; plastic bags therefore become a new and low-cost storage method for small producers.