Ripening Evaporators for Avocado Ripening Room

Ripening Evaporators for Avocado Ripening Room

A ripening evaporator operates as a key component in the climate control system of an Avocado ripening room, working alongside a refrigeration cycle to regulate temperature and humidity—critical for consistent fruit ripening. Its function is tailored to maintain the precise conditions (18–20°C/64–68°F and 85–90% RH) that Avocado requires.

The ripening evaporator is part of a closed-loop refrigeration system, connected to a compressor, condenser, and expansion valve. This system circulates a refrigerant (e.g., R134a, R290, or other food-safe options) to transfer heat and control the room’s climate.

Refrigerant state at entry: The evaporator receives low-pressure, low-temperature refrigerant (typically a gas or liquid-vapor mix) from the expansion valve. This valve reduces the refrigerant’s pressure, causing it to cool rapidly.

Heat absorption: Warm air from the ripening room is drawn over the evaporator’s cold coils (via fans). Heat from the air transfers to the refrigerant, raising the refrigerant’s temperature and causing it to evaporate (turn from liquid to gas).

Air cooling: As heat is removed, the air from the room cools to the target temperature (18–20°C).

Avocados require 85–90% RH to avoid shriveling or mold. The evaporator balances moisture through:

Condensation control: When air cools, its ability to hold moisture decreases. Excess humidity in the room condenses on the cold coil surfaces (like dew on a cold glass).

Drainage: Condensed water is collected in a pan and drained out of the room, preventing moisture buildup that could lead to mold.

Humidity sensors: If the room is too dry, the system adjusts fan speed or coil temperature to reduce condensation, retaining more moisture in the air.

Fans: Strategically placed fans pull warm, humid air over the coils and push cooled, dehumidified air back into the room. This creates a continuous cycle, ensuring uniform temperature and humidity across all Avocados (no "hot" or "cold" spots).

Laminar flow: The design promotes smooth, even airflow around stacked fruits, ensuring every cantaloupe is exposed to the same conditions.