How to sterilize Jars and Caps for proper food preservation and home canning.

There are several methods to sterilize jars, such as boiling them in water, using the microwave or the oven for instance, or the washing machine.

When preserving fruit or vegetables it is best to store them in glass jars.  We get lots of products sold in jars, so if you like preserving fruit or vegetables you can recycle them by using them over and over again.

When you use a jar wash it well with hot water and soap and put it away. When you decide to make your preserves wash both jars and lids again with hot water and soap and rinse them well.

In a big pot put a new, clean sponge cloth and put your jars standing up with water to cover them. Boil them for fifteen minutes.  Turn off the heat and add the lids as well.  Wait until they cool. Remove with tongs and place them on clean kitchen towels upside down, to dry before filling them.

This is the old method I used to use. I don’t use this method any more as for several years I put the clean jars and lids in the washing machine and run through a regular circle at the highest temperature (65 degrees C).

This method has been working for me for years,  but it’s up to you to chose which method you trust or like best.

Update:  25 June, 2013

Unfortunately, now that we have moved to the village, I do not have a washing machine nor a microwave oven, so I had to adapt again to the older method of sterilizing the jars.  I tried boiling them but the water here is very hard so when boiling the jars they become covered with a white dust from the residues of the minerals and the pot also becomes hard to clean.

The only thing left for me to do is use the oven.

What I did is I preheated the oven to 150 degrees Celsius,  fan forced with both top and bottom elements on.

I put the jars in and lower the temperature to 120 degrees Celsius.  I heated them for fifteen minutes and turned the oven off.  I let them sit in the oven until they cooled.  (However, if you are in a hurry, you can take them out quicker but leave them at least fifteen minutes inside).

Here is a Re-Cap:

How to Sterilize Jars and Caps for food preserving:

Boiling Water Method (Most common):

Steps:

1. Wash jars and caps in hot, soapy water and rinse well.
2. Place jars in a large pot and cover completely with water.
3. Bring to a full boil and keep boiling for 10 minutes (add 1 extra minute per 300m altitude if relevant).
4. Keep jars in the hot water until ready to use.
5. Remove with clean tongs and place upside down on a clean towel.

Caps:

• Most modern lids (like those from Ball or Kerr) should not be boiled. Just wash and keep them in hot (not boiling) water to soften the sealing compound.

Oven Method (for jars only):

Steps:

1. Preheat oven to 120°C (250°F).
2. Wash jars and place them upside down on a baking tray.
3. Heat for 15–20 minutes.
4. Leave them in the oven until needed.

Do not put lids/caps in the oven (the sealing ring can be damaged).

Dishwasher Method (Convenient):

Steps:

1. Place jars in the dishwasher.
2. Run the hottest cycle or sanitize setting.
3. Keep the door closed until you’re ready to use them (so they stay hot).

Important Safety Notes

• Always fill jars while they are still hot to prevent cracking.
• If you’re doing full canning (water bath or pressure canning), sterilization may already occur during processing, depending on recipe and time.
• Never reuse damaged lids or jars with cracks.

Now your jars are ready to be filled up.

Good luck with whatever you are preserving.

Kopiaste and Kali Orexi,