Earlier quoted context omitted.
This is awesome. Less dramatically, when I lived in Germany, where I had radiators for heat, I stored baby bottles of water on top of the kitchen radiator. It kept the water the perfect temperature for my infant with zero risk of it being too hot, so zero risk of scalding. All I had to do was add powdered formula when he got hungry.
For infants this is not food safe. The powder should be mixed with water that is at least 70C to kill bacteria that might be present in the powder. For older babies (6+) then maybe not so important. In the weaning period when I took over with a night bottle and the wife shut down her boobs I would just sleep with a pre-mixed (not from powder) formula pack next to my body. It would be more or less body temperature and…
https://www.cdc.gov/nutrition/InfantandToddlerNutrition/form...
Edit: This also seems like a recent development. My children are grown.
https://foodpoisoningbulletin.com/2022/timeline-chronobacter...