i used glass bottles had to go back to work after 6 weeks sterilize bottles, formula was boiled?? gosh i don't remember but i know it wasn't instant like today where you just add water or do they even do that, i cooked and pureed his food only thing baby food he ate was cereals and applesauce cloth diapers and bibs.............gosh that was 48 yrs.......my one and only