My previous post regarding steins as a possible identification of the ‘jars’ in the recipe pages seems a bit ludicrous after discovering a near obvious solution to what they may be.  Apothecary pots fit not only purpose but also physical description and the fact that they are typically labeled by name just like it appears in the VMS.  I believe my final conclusion is solved unless someone can lead me away from this idea.

Visual Examples: https://www.pinterest.com/pin/13229392628960052/?lp=true

 

Apothecary Pots https://www.palazzodeiconsoli.it/en/sezione-ceramiche/

The pharmaceutical jars constitute an important part of the collection if only because of their number. They were donated to the Museum by the “Ente Ospedaliero” of Gubbio. Since the Middle Age, together with glass, pottery has been the preferred material for conserving herbs, drugs and the various ingredients used in the preparation of medicines, as it is both practical to use and easy to clean. From the middle of the 15th century it became usual to write on the pot the name of the substance it would contain or to leave the cartouche blank so that a paper label could be attached.
The oldest part of the collection consists mainly of bottles for containing liquid medicines (rounded jars with cylindrical necks and small tubular spouts), and a series of apothecary jars (cylindrical majolica jars with a narrow waist and low neck used to contain denser or oily preparations or herbs). The remaining exhibits are examples of crucibles and steam domes for stills used in distillation.