Why does round lettuce appear spot during cold storage？（0~4℃）Is it still edible?
I would like to extend the storage time.
Lettuce is packaged with other vegetables, like red chicory, NewZealandspinach, Romaine Lettuce, etc.
May be my expression is not clear, my English is very poor, please forgive me. I want to know the reason of the spotting, so I can avoid it.