Condensed milk is different from ordinary milk. Condensed milk is refined by adding sugar and palm oil after milk is concentrated (but now some merchants only add a little milk or even no milk at all), so basically the main ingredients inside are oil and sugar, both of which are not perishable foods, so as long as you don't dip anything else with a spoon, the shelf life can be very long. I tried it for a month and a half, and it didn't break.

However, it is recommended to put it in a condensed milk container when storing, that is, the kind where the whole can of condensed milk can be put in and covered with a lid, and the ants can be isolated by drainage to avoid angering the ants.