Sec. 1.4. Method of producing vitamin D milk

The following procedures for increasing the vitamin D content of milk to at least 400 U.S.P. units per quart are hereby approved:

(a) adding concentrate of vitamin D to milk prior to and at the place of pasteurization;

(b) directly irradiating milk by means of ultraviolet or carbon arc rays prior to and at the place of pasteurization; and

(c) feeding irradiated yeast to the cow or cows on the dairy farm.