A pass-through system and method for treating and/or pre-cooling perishable products uses a conveyor system with a treatment chamber that is configured to be contained (or closed) to provide a sealed environment and enhanced with forced air flow to recirculate air and/or functional substances including, e.g., sanitizers, as well as ripening management and conditioning agents, across the surface of perishable products. The enhanced forced air is an integral part of the system for efficient treatment and can also be cooled to accomplish rapid cooling.