Posted 21 August 2007. Crop Management.
Rice Harvest Timing Affects Net Returns
University of Arkansas. bumperscollege.uark.edu
Stuttgart, Arkansas (August 15, 2007)--The price a farmer receives for a crop of rice can be reduced by 30 to 40 cents a bushel or more due to reductions in milling quality caused by harvesting too early or late, said Terry Siebenmorgen, a university professor of food science in the University of Arkansas System’s statewide Division of Agriculture.
Moisture content of rice kernels at harvest is a major indicator of milling quality, said Siebenmorgen.
Rice harvested too early, with moisture content of 22 percent or higher, will have many immature kernels that tend to break during milling, Siebenmorgen said. If allowed to dry too long in the field, kernels tend to fissure after rewetting by rain or dew.
Variation in harvest moisture content is unavoidable, Siebenmorgen said, but the target is about 18 percent for the highest net return. Higher moisture content of up to 21 percent for long grain rice will result in fewer fissured kernels and greater milling quality, but the cost of drying the wetter rice offsets the advantage of fewer brokens, he said.
“Overall, when we look at milling quality variations and drying costs, the optimal harvest moisture content for the best net return to the farmer is approximately 18 percent” as an average across all varieties and environmental conditions, Siebenmorgen said.
The findings are based on five years of data collected and analyzed by Siebenmorgen, plant physiologist Paul Counce at the Rice Research and Extension Center, and food science research associates Rusty Bautista and Redentor Burgos.
The researchers are working to fine tune harvest moisture content guidelines for each rice variety. The goal is to provide an optimal harvest moisture content range for each variety in the results of annual variety performance trials published by the Division of Agriculture.
The new guidelines will also consider environmental conditions such as nighttime air temperature, which can greatly affect milling quality, Siebenmorgen said.
Siebenmorgen is director of the Division of Agriculture’s Rice Processing Program, which is supported by major rice millers and allied companies and the Arkansas Rice Research and Promotion Board, which administers checkoff funds provided by farmers.