Sounds like you're pretty well prepared, particularly on the airplane snacks thing. We went to Paris for a week in May, I managed the whole thing with a carry on only, as we had access to laundry in the apartment we rented, and I would imagine that would be the case for you with family. Can't comment on the coconut oil or baking soda for travel...hopefully it won't cause any issues. Probably you'll be fine. Though I'd expect the coconut oil might fall into the liquids/gel categories for carry on stuff. If you run out, perhaps olive oil would make an ok substitute? Food should be divine, I was in Venice/Verona and cruised around Italy 2 years ago and LOVED it. On the list to return one day, particularly to Tuscany. I'm jealous!! Have a great holiday.