A fuel supply system includes a first component configured to direct a fuel flow to a combustor of an engine system. The first component includes a first inner surface and a first outer surface. The fuel supply system also includes an outer coating disposed on the first outer surface of the first component. The outer coating is configured to thermally insulate a first interior of the first component to reduce non-catalytic coke formation in the first interior. Additionally, the fuel supply system includes an inner coating disposed on the first inner surface of the first component. The inner coating is configured to reduce the fuel flow from contacting a base material of the first inner surface of the first component to reduce catalytic coke formation in the first interior.