The footnote notes that items such as vinegar and clarified butter readily fall within the idea of idam, while the treatment of meat, eggs and cheese can require further consideration. The example illustrates why an immediately assumed translation does not always settle a legal expression's scope.
A careful approach asks:
1. What exactly did the oath say?
2. How is idam used in the relevant linguistic custom?
3. What evidence favors including this food?
The solution requires inquiry followed by reflection, not mechanically treating every edible item as equivalent.