Tremella stew is not rotten because tremella leaves are thin. Thin leaves without meat will be stronger and tougher than tremella leaves with thick leaves. Tremella meat with thick leaves absorbs water more easily, so it will be bigger and easier to cook when soaked in water than tremella meat with thin leaves. The average tremella will boil in an hour and is rich in gum. If it is not cooked well, it may be old tremella or chemical tremella.