Sterilzzare i vasetti per le conserve

How to Sterilize Glass Jars for Canning

Among the basic steps for food canning, whether it is a jam, a sauce or vegetables in oil, is sterilizing your glass jars.
You absolutely need to learn how to do it, so that your food will keep healthy a long time.
To do that, you can chose among 3 different methods: by using a pot, the oven, or the microwave oven.

How to Sterilize Glass Jars in a Pot

Pot method is the traditional one, and the longest one, too:

  1. Put a clean cloth on the bottom of a large pot.
  2. Place jars and lids, upwards, in the pot, and put another cloth among them, so that they will not knock against each other.
  3. Fill the pot (and the jars) with cool water, bring to a point of boil, and let boil for 30 minutes.
  4. Then, turn the gas off and let cool down.
  5. Finally, take away and empty your jars, and let them dry, downwards, on a clean cloth.

How to Sterilize Glass Jars in the Oven

Another method much in use recently, as quite quick, is baking jars:

  1. Preheat the oven at 100°C.
  2. Once hot, put the jars inside (with no lids). After 5 minutes, turn the oven off.
  3. When temperature starts to decrease, put also the lids inside. Let jars and lids cool down in the oven.

How to Sterilize Glass Jars in a Microwave Oven

Microwave oven is another quick solution to sterilize jars. Unfortunately, you can’t use it for lids! So, I suggest to use it just for hot food, like jams, as then you will have to turn the jars upside down. In this way, hot jam will sterilize the lid as well.
So let’s see ho to sterilize jars with microwave oven:

  1. Put some water into the jars (about an inch) and put them (with no lids!!) in the microwave oven.
  2. Turn the oven on at the max temperature, and bring to a point of boil (a couple of minutes will suffice).
  3. Take the jars out, and empty them
  4. Let dry completely, downwards, on a clean cloth.

How to Sterilize Full Glass Jars

This method is usually used for jams, sauces, fruit juices… and not for vegetable in oil or pickles, as oil and vinegar are great food preservatives yet.
This method is very similar to the one to sterilize empty jars in a pot. So, you can just follow the same instructions (of course you will not have to fill the jars with water!), just with full and closed jars.

How to Create a Vacuum in the Jars

To store your food preserves in a safer way and for a longer time, you need to create a vacuum in your jars. You just have to fill your jars with the hot food (for example a jam), leaving just about a inch from the edge, close the jar tightly, and turn the jars upside down. Let cool down while still upside down.
For vegetables in oil or vinegar, completely cover the vegetables with oil/vinegar, tap the jar on the table (so that any air bubble will disperse), and put the lid on.
To check if you’ve actually created a vacuum, push your finger in the middle of the lid: a slight depression will show that they have been properly sealed. Otherwise, there is still some air in your jar.