Ladies , what method do you guys use when washing bottles ? I've noticed when I soak & wash with…

Ladies , what method do you guys use when washing bottles ? I've noticed when I soak & wash with soap and super hot water I can still smell formula ... My son has 7 bottles in total and once he has 5 dirty I boil them after every single use and I've noticed the nipples and the bottles look a lot cleaner and have no smell what so ever ... Is there any other quick way ?