How to determine if a string is 'food' or 'drink'?
Menu is generally a list of items served in restaurant. Items broadly divided in to two sections:


Food: Where all food items are listed
Drinks: Where all drink items are listed.


If all restaurant menus that you have, listed items in similar way, I'm bit confused how you will use ML in this case.

But if restaurant menu includes recipe/ ingredients of the food/drink items, then yes I can apply machine learning in order to identify the category of an item.
In such a case we can use NLP or simple text classifier(by dividing the recipe in some key word tokens and segregate between food and drink)model for prediction.