Silo bolsa en la Argentina

The storage of grains in plastic bags is a practice that began in the mid-1990s in the Argentine Republic, and spread rapidly from the two million tons stored in the 2001/2002 harvest, to 40 million tons in the 2013/2014 harvest (about 40% of the country's total grain production is stored in silo-bags). Postharvest activity is aimed at minimizing grain losses both quantitatively and qualitatively from the harvest in the field, through the conditioning and storage, and culminating in the final use of the grain, either as an input of an industrial process or to eat as food. Successful storage means that the grain that enters the silo must be dry, healthy, clean and cold, and it must be maintained in these conditions. Traditional storage is done in a normal atmosphere, which means important infrastructures and constant monitoring. Storage in a modified atmosphere, typically in a silo-bag, allows a much more flexible management of the products, since it can be implemented in the field itself, on demand, with a conservation of at least 12 months, using a simple, low cost and efficient machinery, following simple management rules. It is in fact the hermeticity of the plastic that allows a process of self-modification of the atmosphere of the bag, achieving the proper conservation conditions in a few days. The main limit of the system is the capacity of the bag to resist external aggressions: spikes, solar radiation, fatigue of the plastic material. There are many advantages of the use of plastic bags in dry grain storage, as store at source at low cost, the versatility of the system and complement with other storage systems, a maximum use of the harvesting equipment (can absorb 3 to 4 harvesters at the same time). It also allows to harvest in the moments in which we cannot take the production from the field. This offers savings in freight, storage and parities. It allows to differentiate qualities or product stored while accessing the grains at any time and store them with higher humidity than in conventional silos, not using insecticides. It is easy to adapt to different productive systems, expands the storage capacity and offers flexibility for the delivery and commercialization times. It can be used with a wide range of other products like fertilizers, malt, wheat small bran, distillates maize remains, brewing barley in addition to the wheat, sunflower, soy, corn, sorghum, rice, kidney beans, cotton, and their seeds, etc. As every other system, silo-bags should be properly handled and monitored, even if the procedure is quite simple, as the internal level of CO(2) is a suitable indicator of the behaviour of the bag content. The risk is measured considering the humidity of the grain, the normal ageing of the bag and the possibility of rupture of the bag by external agents. It is important to bear in mind that these risk values are indicative, they are not absolute and may vary in different situations. They can be resumed by the following guidelines: increasing the ambient temperature, the risk increases. When the grains are damaged, the risk increases. When the grains are dirty (impurities) the risk increases. As humidity is the major factor of evolution of the products stored, it serves as principal indicator to guide in the storage of dry grains in plastic bags, according to the risk table below. The management of silo-bags will be done according to the risk table: the more risky is a bag, the quicker it should be emptied.