Broken Corn and Foreign Material (BCFM)
Broken corn and foreign material (BCFM) is an indicator of the amount of clean, sound corn available for feeding and processing. The lower the percentage of BCFM, the less foreign material and/or fewer broken kernels are in a sample. Higher levels of BCFM in farm-originated samples generally stem from harvesting practices and/or weed seeds in the field. BCFM levels will normally increase during drying and handling, depending on the methods used and the soundness of the kernels. More stress cracks at harvest will also result in an increase in broken kernels and BCFM during subsequent handling.
Broken corn (BC) is defined as corn and any other material (such as weed seeds) small enough to pass through a 12/64th-inch round-hole sieve, but too large to pass through a 6/64th-inch round-hole sieve.
Foreign material (FM) is defined as any non-corn material too large to pass through a 12/64th-inch round-hole sieve, as well as all fine material small enough to pass through a 6/64th-inch round-hole sieve.
The diagram shown below illustrates the measurement of broken corn and foreign material for the U.S. corn grades.
Average U.S. Aggregate BCFM in 2016 (0.7%) was slightly below 2015, 2014, and 5YA (all 0.8%), and well below the maximum for U.S. No. 1 grade (2.0%).
The variability of BCFM in the 2016 crop was slightly less than previous years’ crops and 5YA, as indicated by standard deviations (0.45% in 2016, 0.61% in 2015, 0.50% in 2014, and 0.58% for 5YA).
The range between minimum and maximum BCFM values in 2016 (4.0%) was lower than in 2015 (11.9%) and 2014 (5.8%).
The 2016 samples were distributed with 96.6% of the samples below the maximum BCFM level for U.S. No. 1 grade (2%), compared to 95% in 2015 and 96% in 2014. BCFM levels in nearly all samples (99.2%) were equal to or below the maximum 3% limit for No. 2 grade.
Average BCFM in all ECAs in 2016 was the same (0.7%). The average BCFM differed by no more than 0.1% in 2015, and by no more than 0.2% in 2014 and for 5YA.