Typical systems use a variable speed conveyor. Product is either run through on pallets or bulk loaded onto the conveyor belt.
The photo shows a unit with a conveyor that is cooling using a submerged pile design. The produce is conveyed into a water bath area with a conveyor belt below the water level.
As the pile builds the product contacts the conveyor belt and between the belt and motion of the water, the produce moves to the discharge end of the tunnel.
High volumes of water are moved to deliver a cold product temperature in a short period of time.