In Germany WECK jars are often used for preserving, but in Italy people often prefer screw-top jars of Bormioli Rocco's Quattro Stagioni series. Preserving in Quattro Stagioni jars is different from the WECK preserving method, but it's also quite simple.
First of all the rims of the Quattro Stagioni jars must be clened carfefully before starting to fill them. Moreover it's important to use always new screw caps. The caps shoudn't be screwed too tightly onto the jars.
Now place the Quattro Stagioni jars into a pot containing lukewarm water. The screw-top jars have to be boiled as long as the recipe says. The preserving time may vary depending on the kind of food that's preserved. After this process let the jars cool down in the same waterbath.
It's essential to control if a vacuum has been created inside the Quattro Stagioni jars. Therefore check if the middle of the screw caps have lowered. If yes the filling goods will have a long durability.
Due to the vacuum some physical effort is required to open the jars. On the other hand you can be sure that the content is still consumable if there is a vacuum.
Quattro Stagioni jars can be reused several times if you clean them poperly. Please note that the screw caps can be employed only once. Otherwise the compound inside the screw caps doesn't have optimal sealing properties.