Bread is explicitly called out as example of an artificial, not a natural item on ArM5 p.77 Creo (Cr) "I Create".
Are you suggesting that AM5 Creo can't create these?
Creo can create artificial things also. But a Finesse roll is in order. Check this on ArM5 p.77 Creo (Cr) "I Create" and on HoH:S p.60 Creo Magic, and find the difficulty of this Finesse roll described on Covenants p.49 box Rego Craft Magic and HoH:S p61 box Ease Factors for Creating and Crafting Objects.
To create artificial things, a magus needs also to be familiar with them (ArM5 p.77). We can assume this for bread, unless the magus never left a medieval version of Buñuel's Las Hurdes (en.wikipedia.org/wiki/Land_Without_Bread ).
We learn from A&A p.70 box Replicating Formulae with Hermetic Magic, that a magus needs to know the specific formula of A&A experimental philosophy to be familiar with A&A p.76 Alchemical Steel.
In general: the more rare and potentially world altering the item to be created might be, the more arcane and specific is the knowledge required to be sufficiently familiar with it.
Cheers