The quality index of cottonseed shall be an index of purity and soundness, and shall be determined as follows:

(a) Prime quality cottonseed. Cottonseed that by analysis contains not more than 1.0 percent of foreign matter, not more than 12.0 percent of moisture, and not more than 1.8 percent of free fatty acids in the oil in the seed, shall be known as prime quality cottonseed and shall have a quality index of 100.

(b) Below prime quality cottonseed. The quality index of cottonseed that, by analysis, contain foreign matter, moisture, or free fatty acids in the oil in the seed, in excess of the percentages prescribed in paragraph (a) of this section shall be found by reducing the quality index of prime quality cottonseed as follows:

(1) Four-tenths of a unit for each 0.1 percent of free fatty acids in the oil in the seed in excess of 1.8 percent.

(2) One-tenth of a unit for each 0.1 percent of foreign matter in excess of 1.0 percent.

(3) One-tenth of a unit for each 0.1 percent of moisture in excess of 12.0 percent.

(c) Off quality cottonseed. Cottonseed that has been treated by either mechanical or chemical process other than the usual cleaning, drying, and ginning (except sterilization required by the United States Department of Agriculture for quarantine purposes) or that are fermented or hot, or that upon analysis are found to contain 12.5 percent or more of free fatty acids in the oil in the seed, or more than 10.0 percent of foreign matter, or more than 20.0 percent of moisture, or more than 25.0 percent of moisture and foreign matter combined, shall be designated as “off quality cottonseed.”

(d) Below grade cottonseed. Cottonseed the grade of which when calculated according to §61.101 is below grade 40.0 shall be designated as “below grade cottonseed,” and a numerical grade shall not be indicated.