Code of Federal Regulations Title 7. Agriculture § 7.51.2292 Damage

(a) Shriveling when more than one-eighth of the portion of kernel is severely shriveled, or a greater area is affected by lesser degrees of shriveling producing an equally objectionable appearance, except that kernels which are thin in cross-section but which are otherwise normally developed shall not be considered as damaged;

(b) Mold when plainly visible;

(c) Discoloration of the meat when more than one-eighth the volume of the portion of kernel is severely discolored, or a greater volume is affected by lesser degrees of discoloration producing an equally objectionable appearance;

(d) Not well dried;  and,

(e) Not clean.