C.S.
TB, I used to heat in the jar. I see no reason why you can't use the jar. It's glass! On the subject of glass, I much prefer feeding my children on glass, ceramic, "real" adult dishes. Why? you don't have to deal with the issue of whether or not the plastic is harmful either to the person eating off of it or the landfill where it will inevitably end up. And then for a more selfish/practical reason, you will end up with many, many less messes to clean up. It is so easy for little ones to spill, tip, bump, throw plastic plates and cups. Plastic cups are especially ridiculous. Little ones don't have the coordination to navigate the minefield that is the dinner table without bumping into things. And then they spill. And we have to clean up. "Real" dishes and glasswear are much more stable. The glasses I use are small, heavy tumblers. My kids have never broken a single one and they rarely ever spill. What's the worse thing that can happen? If they drop it and it breaks, they are in their chair and won't get hurt. Believe me, you will have many, many , many fewer spills to clean up if you get rid of the silly plastic and get nice, heavy little glasses. The plastic cups are only used in the bathroom. Even when my kids (5 and 3) were in a high chair, I fed them with adult plates. I think children appreciate being treated like the rest of the family. Good luck keeping things green!