Grain Storage and the Impacts of Increasing Temperature

Weather data, acquired from the Midwestern Regional Climate Center (MRCC), indicated that the Howard County October through December 2015 mean air temperatures were 6ºF above normal. Monthly mean air temperatures are comprised of an average of minimum and maximum temperatures for each respective month. The MRCC database can be obtained at the following url http://mrcc.isws.illinois.edu/CLIMATE/. For December alone the mean air temperature was 40ºF, which is nearly 12ºF above normal for the month. Due to the warmer temperatures, there may be concern for deterioration of stored grains. Spoiling of stored grain is mainly tied to temperature, grain moisture content, insect exposure, and molds (Lawrence et al., 2013). Grain temperature and moisture are influenced by the natural heating from the sun and the thermal properties of the storage bin. Elevated insect and mold activity within the stored grain can result in further temperature increases (Lawrence et al., 2013). Managing stored grains can be a difficult task and can result in economic losses if poor management practices are applied.

Mold prevention practices should be implemented when managing stored grain. To prevent contamination from a previous year’s grain, thoroughly clean all equipment inside and out before harvest. Grain should be dried until a safe moisture is reached. Storing grain at a moisture of 0.5 to 1% less than normal could decrease the risk of exposure to mycotoxins, which are health hazards to both animals and humans (Erickson et al., 2010). Cooling the grain temperatures (between 35 and 40ºF) as the outside air temperature drops will reduce fungal activity and deterioration of the grain (Erickson et al., 2010). Once the grain reaches proper temperatures, it is important to keep the grain cool throughout the winter. Periodic, warmups can cause unwanted grain temperature increases (Maier et al., 1995). As grain temperatures reach greater than 60ºF, the conditions within the bin can be favorable for insect damage and fungal activity. In order to minimize the potential increase in grain temperature, it is important to seal fans and ducts to reduce the amount of warm air leaking into the bin. By covering these access points for rodents and insects, the potential for grain loss can also decrease. Routinely checking the grain storage facility for temperature, moisture, mold, and insects can help remediate grain loss. Other management practices, such as leveling and coring, will reduce the grain warming potential (Maier, 1995).

If handling moldy grain is necessary, be sure to wear a respirator to keep smaller particles from entering your body. Spores could also stick to clothing, so changing clothes immediately after handling moldy grain can reduce your risk of becoming sick. If exposed to the mold and become sick, seek immediate medical attention (Erickson et al., 2010). Please feel free to contact the Howard County Extension Office for questions or further information regarding proper grain storage.

Sources

Erickson, B., Field, B., Lemenager, R., Roberts, M., Stroshine, R., 2010. Managing Moldy Grain. Purdue Extension. ID-418. www.purdue.edu/cornmold

Lawrence, J., Maier, D.E., Stroshine, R.L., 2013. Transactions of the ASABE, American Society of Agricultural and Biological Engineers 56 (1): 179-188.

Maier, D.E., Mason, L.J., Woloshuk, C.P., 1995. Keeping Cold Grain Cold. Purdue University. Grain Quality Task Force. Fact Sheet #21.

Midwestern Regional Climate Center. Cli-MATE: MRCC Application Tools Environment. Generated at 01/05/2016 12:35:33 PM CST.