Zonfrillo died in Melbourne on Sunday, MasterChef Australia confirmed on Monday afternoon.
"Network 10 and Endemol Shine Australia are deeply shocked and saddened at the sudden loss of Jock Zonfrillo, a beloved member of the MasterChef family," a statement from the program said.
"Jock was known to Australians as a chef, best-selling author, philanthropist and MasterChef judge but he will be best remembered as a loving father, husband, brother and son."
