Expired nori should not be eaten.
Any food in life has a certain shelf life, eat in the shelf life, can ensure the safety of food. The general shelf life of seaweed is about 1 to 2 years, after the expiration date can not be eaten, even if the seaweed did not open or the appearance of mold phenomenon, at this time the safety of seaweed can not be guaranteed.
And long time storage of purple cabbage, the internal decay may have occurred deterioration phenomenon, if you continue to eat, may trigger gastrointestinal discomfort, nausea, vomiting, diarrhea and so on.
Daily in eating purple cabbage, try to intake in the shelf life of the food, but also to put the purple cabbage in sealed conditions to save, avoid long time in the humid environment to save, easy to lead to purple cabbage mold.