Sustaining grain quality in storage

Focusing on grain quality can benefit grain handling facility's bottom line, improve end product for entire retail chain and enhance safety.

DESPITE the late planting and cooler-than-normal temperatures during critical development stages, this year's grain crop was larger than anticipated, but a short crop year in 2012 had many farmers harvesting a wetter crop early.

Bob Marlow, central region operation manager for The Andersons Inc., told the National Grain & Feed Assn.'s Country Elevator Conference that, in general, most crops were harvested in a timely fashion with fewer problems than expected.

Nevertheless, the large volume of high-moisture harvested corn had many grain handling facilities struggling with storage management. As a result of holding wet corn too long prior to drying, some mycotoxin activity has already appeared, Marlow reported.

The length of time corn can be properly stored is dependent on the temperature and actual corn moisture. For example, corn with a moisture level of 28% can be stored for 50 days at 35 degrees F, while the same corn can be stored for only three days at 75 degrees F, a temperature that was seen during the early months of harvest this year.

Early mold development activity has been reported. Since Blue Eye mold, caused by Aspergillus glaucus, is naturally occurring, it is very possible that the mold was carried over from the past year if grain bins were not properly disinfected prior to refilling them with the 2013 crop. Blue Eye grows best at moisture levels greater than 15% and will remain dormant until temperatures and moisture reach an ideal growing environment.

Additionally, second-crop soybeans are causing some operational and quality concerns since the majority of the farming operations across the Corn Belt were a month behind on spring planting. With harvest moisture well above 20%, if not properly preconditioned, those soybeans will experience larger problems in the short term.


Grain quality benefits

Good grain quality provides many benefits. Grain quality gives grain handling facilities the ability to carry the crop forward to satisfy future demand during the year and to capture premiums or increase income by providing the end user with a quality product. In addition, it reduces financial risk with quality shrink.

Perhaps more important, addressing grain quality can reduce the risk to workers.

"We have the ability to impact and eliminate the need to enter a confined space when the grain is flowing," Marlow said.

As Purdue University reported in its 2010 summary of grain entrapment in the U.S., a direct relationship exists between "out-of-condition" grain and grain entrapment.

Approximately 70% of all documented entrapments occurred on farms or other locations currently exempt from the Occupational Safety & Health Administration grain handling facility standards.

With on-farm storage capacity increasing, the potential for the number of grain entrapment incidents is likely to rise.

Historically records of U.S. grain entrapments showed that years with large grain crops like 2010 also had more entrapment incidents. Therefore, a general concern exists for an increase in incidents associated with the 2013 crop.

Jointly, grain handling facilities could play a pivotal role in reducing the future number of grain entrapments, but they must assist in efforts to educate customers, especially those with on-farm storage.

"It's something, as an industry, that we can make an impact not only at our facilities but also with our customers," Marlow concluded. "I believe our goal as an industry, as whole, is to get that number to zero."


Maintaining quality

Maintaining grain quality starts with prescribing to the S.L.A.M. principle, a strategy developed by Purdue. S.L.A.M. represents four proactive steps: sanitation, loading, aeration and monitoring.

While the first two steps need to be completed prior to harvest, aeration and monitoring duties should be performed for the life of the stored grain.

During aeration, the first phase is to complete initial cooling by dropping the temperature 40-45 degrees F and gradually reducing it until the target temperature of 25-35 degrees F is reached. It is important to maintain the target temperature with intermittent fan operation to reduce mold and insect activity.

Keeping the grain cool is dependent on ventilating the head space. As daytime temperatures increase, running roof ventilators to reduce headspace temperatures is necessary, or a second crop will sprout. A thermostat control on roof ventilators may be a viable option for monitoring purposes.

Routinely checking the temperature, mold, moisture and surface of the grain is necessary for its long-term shelf life in storage.

Marlow warned that there are some limitations to traditional inspection methods, such as human sensory skills that can vary from person to person, temperature cables that can detect heat only at a relatively close distance to the cable and economics that may limit a facility from properly sampling and/or transferring.

Ideally, if all grain management is on track and cool temperatures are maintained, 12-14% moisture corn can be stored at 40 degrees F for five years without sacrificing quality.

Volume:85 Issue:52

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