Vacuum Cooling to Reduce Losses in Leafy Vegetables and Brassicas

Pre-cooling is essential to maintain the quality of leafy vegetables and brassicas after harvest. In products such as lettuce, cabbage, or celery, insufficient cooling accelerates dehydration, promotes deterioration, and shortens commercial life. To prevent this, Moelco Levante applies vacuum cooling technology through Vacuum Cooler units designed specifically to stabilize the product in the first minutes after harvest.

Leafy vegetables have a high surface-to-volume ratio, which makes them particularly sensitive to residual heat. If this heat is not removed immediately, respiration increases and the product loses firmness and moisture. Vacuum pre-cooling allows rapid and homogeneous removal of this heat, improving behavior during storage and refrigerated transport.

Vacuum Technology for Fast and Uniform Cooling

The Vacuum Cooling system works by inducing partial evaporation of the moisture present in the product when pressure is reduced inside a hermetically sealed chamber. This evaporation absorbs thermal energy and enables a rapid temperature drop.

According to Moelco Levante, the process allows the following:

• Introduction of cold into the core of the product in cycles lasting 20 to 40 minutes.

• Reduction of temperature from ambient levels to values close to 2 °C.

• Maintenance of thermal stability before the product enters the cold storage room.

This initial pre-cooling reduces enzymatic and microbial activity, two critical factors in the postharvest deterioration of leafy vegetables and brassicas.

Application in Leafy Vegetables and Brassicas

The technology is particularly effective in products with a large exposed surface area, such as lettuce, cabbage, celery, and other leafy vegetables. The treatment reduces wilting, prevents loss of firmness, and helps maintain visual quality throughout the cold chain.

Equipment and Operating Cycle at Moelco Levante

The systems developed by Moelco Levante integrate process chambers, vacuum pumps, internal refrigeration systems, and safety components. The cycle begins with pallet loading, automatic door closure, and the application of vacuum. Part of the surface water evaporates and removes heat, while the refrigeration system condenses the vapor to ensure process stability.

Vacuum Cooling helps extend shelf-life, improve commercial appearance, and reduce the cooling demand in conventional storage rooms. It also facilitates long-distance transport and harvest planning. Moelco Levante complements this technology with manufacturing, maintenance, refurbishment, rental services, and the supply of specific spare parts.

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