Home

Corn Export Cargo Quality Report 2018/2019

Contents

  1. Export Cargo Quality Highlights
  2. Introduction
  3. Grade Factors
  4. Quality Test Results
  5. Moisture
  6. Chemical Composition
  7. Physical Factors
  8. Stress Cracks
  9. 100- Kernel Weight
  10. Kernel Volume
  11. Kernel True Density
  12. Whole Kernels
  13. Horneous (Hard) Endosperm
  14. Mycotoxins
  15. Assessing the Presence of Aflatoxins and Deoxynivalenol (DON)
  16. Background: Mycotoxins General
  17. Background: Aflatoxins
  18. Background: Deoxynivalenol (DON) or Vomitoxin
  19. U.S. Corn Export System
  20. U.S. Corn Export Flow
  21. Impact of The Corn Market Channel on Quality
  22. U.S. Government Inspection and Grading
  23. Survey & Statistical Analysis Methods
  24. Survey Design & Sampling
  25. Statistical Analysis
  26. Testing Analysis Methods
  27. Grade Factors
  28. Moisture
  29. Chemical Composition
  30. Physical Factors
  31. Mycotoxins
  32. U.S. Corn Grades & Conversions

Chemical Composition

The chemical composition (protein, oil, and starch concentrations) of corn is measured using near-infrared (NIR) transmittance spectroscopy. The technology uses unique interactions of specific wavelengths of light with each sample. It is calibrated to traditional chemistry methods to predict the concentrations of protein, oil and starch in the sample. This procedure is nondestructive to the corn.

Chemical composition tests for protein, oil and starch concentrations were conducted using a 550 to 600-gram sample in a whole-kernel Foss Infratec 1241 NIR instrument. The NIR was calibrated to chemical tests, and the standard error of predictions for protein, oil and starch concentrations were about 0.27%, 0.26% and 0.65%, respectively. Comparisons of the Foss Infratec 1229 used in Export Cargo Reports prior to 2016/2017 to the Foss Infratec 1241 on 21 laboratory check samples showed the instruments averaged within 0.25%, 0.26% and 0.25% of each other for protein, oil and starch, respectively. Results are reported on a dry basis percentage (percent of non-water material).