Place the scallops into the bowl of a food processor and pulse 4 to 5 times. Add the egg whites and pulse until combined. Scrape down the sides of the bowl and add the salt, pepper, nutmeg, lemon zest, and parsley. Pulse to incorporate. With the machine running, slowly add all of the cream. Scrape down the sides of the bowl one last time, put the lid back on, and run for 5 more seconds.