(a) wheat flour, corn flour and related products;
(b) bread, rolls and related bakery products;
(c) milled rice;
(d) macaroni and noodle products. 2. The standards of enrichment so established may prescribe maximum and minimum amounts of vitamins, minerals and other nutrients which enriched products must contain, or such standards may prescribe single level requirements, with provisions for a reasonable overage within the limits of good manufacturing practice. In establishing such standards of enrichment, the commissioner shall conform, insofar as he finds practical, to standards of enrichment promulgated by the secretary of health, education and welfare pursuant to the federal food, drug and cosmetic act, and acts amendatory thereof. Any standard established by the commissioner after public hearing may be amended without hearing, if the amendment substantially conforms to standards promulgated under the federal act.