Administrative Rules of Montana
Department 32 - LIVESTOCK
Chapter 32.12 - EGGS
Subchapter 32.12.2 - Montana Standards For Quality Of Individual Shell Eggs
Rule 32.12.205 - TERMS DESCRIPTIVE OF THE YOLK

(1) An "outline slightly defined" (AA quality) yolk is a yolk outline that is indistinctly indicated and appears to blend into the surrounding white as the egg is twirled.

(2) An "outline fairly well defined" (A quality) yolk is a yolk outline that is discernable but not clearly outlined as the egg is twirled.

(3) An "outline well defined" (B quality) yolk is a yolk outline that is quite definite and distinct as the egg is twirled.

(4) An "outline plainly visible" (C quality) yolk is a yolk outline that is clearly visible as a dark shadow when the egg is twirled.

(5) A "slightly enlarged and slightly flattened" (B quality) yolk is a yolk in which the yolk membranes and tissues have weakened somewhat causing it to appear slightly enlarged and slightly flattened.

(6) An "enlarged and flattened" (C quality) yolk is a yolk in which the yolk membranes and tissues have weakened and moisture has been absorbed from the white to such an extent that it appears definitely enlarged and flat.

(7) A "practically free from defects" (AA or A quality) yolk is a yolk that shows no germ development but may show other very slight defects on its surface.

(8) A "definite but not serious defects" (B quality) yolk is a yolk that may show definite spots or areas on its surface but with only slight indication of germ development or other pronounced or serious defects.

(9) An "other serious defects" (C quality) yolk is a yolk that shows well developed spots or areas and other serious defects, such as olive yolks, which do not render the egg inedible.

(10) A "clearly visible germ development" (C quality) yolk is a yolk in which the development of the germ spot of a fertile egg that has progressed to a point where it is plainly visible as a definite circular area or spot with no blood in evidence.

(11) "Blood due to germ development" is blood caused by development of the germ in a fertile egg to the point where it is visible as definite lines or as a blood ring. Such an egg is classified as inedible.