Just Bento

Bentos are meant to be eaten at room temperature and if its not hot outside you do not need to cool the traditional recieps. Normally I make my bento in the morning and eat it around 12 in the morning. And it has always been in best shape. Only in summer you should think about cooling you bento.

I would recomending putting a little extra salt or some sushi vinigar in your rice, and avoid animal based foods (especially fish). Pasta and bread are fine as well as rice. You could also get a thermal lunch box to keep things nice and hot. Of course from a food hygene point of veiw that would be worse, but if you stick to low risk foods it's still perfectly safe. Using a thermal lunchbox/bento can also keep things cool, which helps from a food hygene point of veiw. Green salad is safe but it wilts horribly at summer room temprature. I have no access to a fridge or microwave at school (how would they provide enough for everyone), and none of my bentos have gone bad yet.

I guess you can put animal-based food only if they are completely and absolutely well cooked... I would avoid fish anyway, even if i can store the bento in a fridge, except for canned tuna. And avoid mayo or anything concerning raw egg.
GOod luck! ^^

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