After having published a post on our website www.sammic.com about food packaging in glass jars, a query was received that relates this system with the subsequent cooking of food, so the post has been moved here.
The question was: once food has been vacuum packaged in glass jars, can it be cooked in the same jars?
The response from our chef about cooking vacuum-packaged foods in glass jars:
There is no problem to place vacuum-packaged jars with food inside into a bain marie at a controlled temperature. What is very important is the heating time in the bain marie and that the minimum temperature of 65°C inside the jar is controlled and stable for at least one hour.
Note that the cooking process can generate juices inside the jars. These juices may affect preparation time. Therefore, in some cases it is advisable to first cook the items and then bottle, pasteurise and store them in a cool, dry place and, if necessary, store them in a refrigerator (in the case of semi-preserved foods).
Remember that steam ovens do not work as autoclaves. That is, they do not generate the temperature required for pasteurisation. Immersion is the best way to transfer, safely and reliably, the temperature to the bottles, bags or container that contains the raw material to be processed.