To sterilize empty jars, put them right side up on the rack in a boiling-water canner. Fill the canner and jars with hot (not boiling) water to 1 inch above the tops of the jars. Boil 10 minutes at elevations of less than 1,000 ft. At higher elevations, boil 1 additional minute for each additional 1,000 ft.
I prefer to use the oven sterilization method (as opposed to the hot water method) which is as follows: Preheat your oven to 275 degrees. Wash each canning jar or mason jar and lid with hot soapy water then rinse but don't dry them. Place each clean jar on a baking tray and place in the oven for 10 minutes.
For this method to be effective, you need to have a “sanitize” setting on your dishwasher. This setting heats the water to a minimum of 150°F, which is hotter than typical dishwasher settings. Put the jars you are sterilizing in the dishwasher with the openings facing down.
Here's the official word from quality assurance team at Ball and Kerr: "We do not recommend baking in any size or shape of Ball or Kerr canning jars. The glass used for Ball and Kerr canning jars is not tempered for oven use and is not meant to be used in baking projects.
Put jars upright on to a baking tray, place tray into a low oven at 110 degrees for about 15 minutes or until jars are completely dry. To sterilise the lids, the best practice is to boil them for 5 minutes and place them on a cooling rack to air-dry.
The Microwave Method
This method of sterilizing is good for regular jam jars but not the Kilner-style or for metal lids. Clean the jars as normal, rinse but leave the jars a little wet. Microwave the jars for 30 to 45 seconds depending on the size of the jar.
When a process time is 10 minutes or more, the jars will be sterilized DURING processing in the canner. Therefore, when process times are 10 minutes or more, pre-sterilization of jars is not needed. It doesn't hurt your product to do it anyway, but it does require additional time and energy and is unnecessary.
Step 4 - Sterilise Your Jars With Boiling Water
Bring to the boil and keep at the maximum temperature for 10 minutes, turn the heat off and cover the pan to keep the jars warm until you are ready to fill them.
ARE MASON JARS DISHWASHER SAFE? Yes! Mason jars can be washed by hand or in the dishwasher. However, the metal Mason jar lids may become worn down by detergents.
The U.S. Food and Drug Administration (FDA) requires that commercial washers (the kind in restaurants) top 165 degrees F in order to sanitize. Anything below 110 degrees F, the FDA says, is too cold to ensure the water can even properly clean organic matter (read: food) from a surface, dish, or pan.
Another thing to note, if your dishwasher won't do a clean and sanitize cycle, just pre-wash the jars and rings ahead of time. For those lids, just set them in hot water for about 10 minutes before using them to seal the jars.
Check the water level. If the water does not cover the jars by 1 to 2 inches, add boiling water as needed. Bring to a rolling boil, cover the canner and boil for 10 minutes if using 4-, 8- or 12-ounce jars or for 15 minutes if using 16-ounce jars.
I notice the CDC IYCF-E guidance provided by Annabelle above says boil for five minutes for sterilizing (which the CDC says should be fine for infants under the age of 2 months or if infants are sick.)
To sterilize empty jars, put them right side up on the rack in a boiling-water canner. Fill the canner and jars with hot (not boiling) water to 1 inch above the tops of the jars. Boil 10 minutes at elevations of less than 1,000 ft. At higher elevations, boil 1 additional minute for each additional 1,000 ft.
Two minutes of microwaving is sufficient for most sterilization.
Surprisingly, your air fryer can be used to sterilise small jars. How to do it: Preheat the air fryer to 120°C/250°F. Place the jars inside and heat for 10-15 minutes.
Heat the oven to 140C/120C fan/gas 1. Wash the jars in hot, soapy water, then rinse well. Place the jars on a baking sheet and put them in the oven to dry completely – this should take around 10 minutes but can vary. If using jars with rubber seals, boil the seals, as dry heat damages them.
Use soapy water to make sure that the jar is clean before sterilising. Take care to rinse off all the washing up liquid. Place in the microwave (while still wet) and turn on 'high' (usually around 1,000 watts) for 30-45 seconds. Place them upside-down on a piece of absorbent kitchen paper (like Plenty) to dry off.
Boil the feeding equipment in a large pan of water for at least 10 minutes, making sure it all stays under the surface. Set a timer so you do not forget to turn the heat off. Remember that teats tend to get damaged faster with this method. Regularly check that teats and bottles are not torn, cracked or damaged.
Oven canning may have been a common home food preservation method years ago, however, science has demonstrated that it is not a safe practice. While it may seem easier or is the latest trend on popular media sites, there are no shortcuts when it comes to safely canning food.
“While canning jars are designed to withstand high temperatures in moist environments, such as those in a canner, they are not suitable for use in the dry heat of an oven. In an oven, glass jars heat unevenly, creating hot and cold spots. …. heat clean jars on a rack in water, not in an oven.”
Check to see if there is a marked "Oven-Safe" symbol underneath the piece. Glass bowls made of borosilicate or tempered glass and marked as oven-safe can go in the oven and withstand high temperatures. Those made of non-tempered glass may not be suitable with heat resistance and withstanding temperature changes.