Grain stored on farm must meet quality standards when sold, such as the GTA (Grain Trade Australia) requirements. It is becoming apparent however, that increasing numbers of grain markets are looking for assurance of food safety.
The contract standards set by GTA do not specifically cover food safety, which is independently audited. There is currently a small percentage of grain marketed directly off farm that is independently tested against a quality assured food safety system such as GrainCare, based on HACCP principles. Approximately 30 businesses currently maintain GrainCare accreditation in Australia.
When food safety is considered, grain storage must be done right, which includes using correct methods of pest control. Poor insect pest control often stems from a lack of storage planning, hygiene, aeration and regular grain checks. When insects are detected in grain, one of the most efficient way to deal with them is a fumigation using phosphine in accordance with label directions. Fumigating with phosphine is considered a pesticide residue free (PRF) treatment so is acceptable to the majority of markets.
The key to success is to start with a pressure tested, gas-tight sealable silo. Follow the phosphine label directions and place the correct dose of phosphine in the silo headspace or a well designed ground application system. Always keep the silo sealed for the required fumigation time period, followed by venting prior to handling. Following labels is part of meeting GrainCare’s food safety standards.
Cutting corners by using phosphine in unsealed or ‘semi-sealed’ storages, reduces the phosphine gas dose and the effective fumigation period. Any ‘off label’ practices may compromise the safety of the grain for human consumption. Furthermore, poor fumigation practices will almost certainly be unsuccessful as a few of the insect life stages, eggs and pupae, will not all be controlled so will continue breeding.
Whilst on-farm grain storage currently relies largely on self regulation, storage management practices are extremely important in securing the future of Australia’s reputation as a supplier of high-quality grains, safe for human consumption.