Grading Guide: Sweet Corn
Illustrated Criteria for USDA Fancy Sweet Corn

USDA Fancy Sweet Corn is:

 
 
Of Similar Varietal Characteristics
For example, do not mix bicolor and yellow ears.
Well Trimmed
Well developed
Three ears on right are not well developed.
 

 

 
 
Fairly Well Filled With Plump and Milky Kernels
Two ears on right are not well filled.
Well-Covered with Fresh Husks
Ear at top right is not well covered. Ear at lower right does not have a fresh husk and is poorly trimmed.
At least 6 inches long (cob)

USDA Fancy Sweet Corn must not have any of these defects:

 
 
 
Smut
Worms or Worm Injury
Insects or Insect Injury
 
 
 
Decay
Clipped Ears
 

Photos below illustrate categories of injury specified in USDA Fancy criteria. Check criteria for allowable limits.

 
 
 
Rust
Discoloration
Bird Injury
 
 
 
Mechanical Injury
Disease
Other Injury

C. Gunter and E. Maynard, Purdue University. 2006. Based on US Standards for Grades of Sweet Corn, 02-12-92 reprinted 01-97. Page last revised 07-25-06.

This project made possible by financial assistance from Indiana's Office of the Commissioner of Agriculture, Value-Added Research Grant Program.

 

 

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Grading Guide: Sweet Corn
Definitions of Criteria for USDA Fancy Sweet Corn

Characteristics of USDA Fancy Sweet Corn:

Similar Varietal Characteristics
Well Trimmed
Well Developed
Fairly Well Filled
  • Similar kernel color
  • Similar character of growth
  • Practically free from loose husks
  • Shank less than 6 inches
  • Shank does not extend more than 1 inch beyond point of attachment of outside husk
  • Ears fairly straight
  • Ears not stunted
  • Kernel rows show fairly uniform development
  • Poorly developed rows do not materially affect appearance and quality
  • Poorly developed or missing kernels at tip extend no more than 1/4 length of cob
  • Poorly developed or missing kernels elsewhere on cob total no more than 1 square inch on a 6-inch cob.
Plump and Milky
Well Covered
Fresh Husks
  • Kernels are well developed
  • Kernel contents are milky, creamy, or clear jelly-like in consistency
  • Husk enclosing ear is tight and undisturbed
  • If husk has been slightly opened, it has been replaced so appearance is not more than slightly affected
  • Fairly good green color
  • Not badly wilted
 

USDA Fancy Sweet Corn does not have any:

Decay
Worm or Insect Injury
  • Decay occurs when bacteria or fungi break down the sweet corn.
  • Visible evidence of insect or worm injury
  • Insect or worm frass

Sweet Corn with injury worse than described below does not meet USDA Fancy criteria. Measurements are based on a cob 6 to 10 inches long.

Rust
Discoloration
Mechanical or Bird Injury, Disease, Indented Kernels
  • Total area on husk is more than 1 square inch
  • Rust extends deeper than 2 layers of husks
  • Total area on husk is more than 3 square inches
or
  • Total area on husk is more than 25% of surface of all blades
  • More than 8 kernels affected
  • Husks penetrated in more than 1 place

Created by C. Gunter and E. Maynard, Purdue University 2006. Based on US Standards for Grades of Sweet Corn, 02-12-92 as reprinted 01-1997. Page last revised 07-27-06.

This project made possible by financial assistance from Indiana's Office of the Commissioner of Agriculture, Value-Added Research Grant Program.