A system for monitoring previously opened, metallically capped containers of baby food stored in a refrigerator for safe consumption thereof and/or allergic reaction thereto, by identifying each such container with a marker that magnetically adheres to the container cap and bears a preprinted legend identifying the day of the week In which the container was opened and stored. The first set of at least seven such markers, each bearing a legend identifying a respective day of the week, is preferably stored on a magnetizable board attachable to the refrigerator. An alternative system uses flexible plastic replacement caps each appropriately pre-marked with a day of the week. In yet another alternative system, a second set of markers is provided and marked so as to distinguish them from markers of the first set, the second set of markers being intended for use to indicate when a new foodstuff is introduced into the baby's diet, thus serving as an positive identifier in the event of an allergic reaction to the new food.