Corn Harvest Quality Report 2017/2018

100-Kernel Weight

100-kernel (100-k) weight (reported in grams) indicates larger kernel size as 100-k weight increases. Kernel size affects drying rates. As kernel size increases, the volume-to-surface-area ratio becomes higher, and as the ratio gets higher, drying becomes slower. In addition, large, uniform-sized kernels often enable higher flaking grit yields in dry milling. Kernel weights tend to be higher for specialty varieties of corn that have high amounts of horneous (hard) endosperm.

Results

U.S. Aggregate 100-k weight in 2016 averaged 35.20 g, higher than 2015 (34.34 g), 2014 (34.03 g), and 5YA (33.89 g).

Variability in the 2016 U.S. Aggregate 100-k weight (standard deviation of 2.43 g) was same as 2015, but less than 2014 (2.83 g) and 5YA (2.71 g).

100-k weight range in 2016 (18.91 to 44.17 g) was greater than 2015 (24.90 to 45.64 g) and similar to 2014 (19.70 to 46.30 g).

The 100-k weights in 2016 were distributed with 54.3% of the samples having 100-k weight of 35 g or greater, compared to 43% in 2015 and 41% in 2014. This distribution indicates a higher percentage of large kernels was found in 2016 than in the previous two years.

Average 100-k weight was lowest for the Pacific Northwest ECA (33.96 g), compared to the Gulf (35.54 g) and Southern Rail (35.67 g) ECAs. The Pacific Northwest ECA also had the lowest 100-k weight in 2015, 2014, and 5YA.