This is artificial jellyfish silk. Artificial jellyfish is made of sodium alginate, anhydrous calcium chloride and alum. Simply put, artificial jellyfish is a chemical mixture. Artificial jellyfish, since they are not eaten in large amounts, are actually harmless. The raw materials of artificial jellyfish, gelatin, sodium alginate and agar, can actually be used as legal food additives.
Of course, although it is harmless to the human body and the taste is close to the crispness of real jellyfish, the nutritional value is not much.