I doubt the glass is specially tempered. They make the containers as cheap and disposable as they can. I think the heat resistance is a function of the thickness of the glass. You probably have seen extremely think beakers in a french coffee press (also cheap and not from borosilicate). I've used hot water in jars just fine to rinse out leftovers and make drinks. Cheap Twist-Off lids secured with 1/6th of a turn can't hold positive pressure. They will lift up and release it. Nobody makes secure lids with a long thread anymore. They could make seal if sucked down with negative pressure. 430ml TO-66 is a relatively tall and narrow jar but still works great, and has the height of a freezer tray.
Great video. Thanks!
👍thanks!
So is a glass broth jar that came from a Passover food box tempered glass?
It should be. The broth was put in the jar while hot so ut should be able to withstand both high and low temperatures.
I doubt the glass is specially tempered. They make the containers as cheap and disposable as they can. I think the heat resistance is a function of the thickness of the glass. You probably have seen extremely think beakers in a french coffee press (also cheap and not from borosilicate).
I've used hot water in jars just fine to rinse out leftovers and make drinks. Cheap Twist-Off lids secured with 1/6th of a turn can't hold positive pressure. They will lift up and release it. Nobody makes secure lids with a long thread anymore. They could make seal if sucked down with negative pressure. 430ml TO-66 is a relatively tall and narrow jar but still works great, and has the height of a freezer tray.
Where I live all preserved food in jars is in tempered glass but this could differ around the world.