Macchinari criogenici - Costruzioni, revisioni, modifiche e ricertificazioni CE

Encrusting machine with liquid nitrogen

Model MecCrust MC 1.5-1.000
  • img_macchinari_mec_construction
  • img_macchinari_mec_construction

Project Detail

Machine details

It is suitable to encrust and freeze, with liquid nitrogen, solid and semi-dense o liquid products in the following industries: food, pharma, industrial. It is usable also as pre-freezing to support gaseous or mechanical freezing tunnel. The encrusting unit can be easily regulated and therefore it can be used on numerous products to be freeze. The process consists of encrusting or freezing the product, mainly foodstuffs, by putting into contact the product itself with a film of cryogenic fluid, inside a vibrating box with linear movement (e.g. vibrating screen).

Thanks to the calefaction phenomenon, the foodstuffs, even if strongly sticky, do adhere neither to the base nor between each other. Furthermore, the direct contact between the products and the cryogenic fluid under extremely low temperature, allows a freezing process almost immediate of the product surface. The cryogenic fluid is made by a non-toxic, non-noxious and inert gas, whose boiling point is -196°C and it is the liquid nitrogen. Vibrators move the vibrating tank containing the liquid nitrogen. Their frequency varies according to the wished speed or to the contact time between the product and the cryogenic fluid. The contact time is on average between 10 and 15 seconds. It may be adjusted according to the angle between the direction of the vibration movement and the tank level, to the tank length and its inclination.

A recycling system, realized with a collecting tank and a cryogenic pump, allows a re-usage of the liquid nitrogen up to its exhaustion. The quantity of vaporized cryogenic fluid during the freezing process is discharged from the operating zone through an extractor hood and its transferring fan.

Working cicle

  1. Filling of the tank for the liquid nitrogen process with the feeding from the storage tank (automatic).
  2. Manual adjustment of the operating parameters: valve of the pump load capacity of the liquid nitrogen, inverter frequency of the moto-vibrator to modify the process speed on the product, leak of the jack stem to modify the tank inclination and its respective liquid nitrogen thickness.
  3. Arranging temperature of the unit thanks to liquid nitrogen circulation for 10 minutes.
  4. Feeding of the products to be encrusted.
  5. End of the feeding of the product to be encrusted.
  6. After 2 minutes interruption of the liquid nitrogen feeding.
  7. After 60 seconds interruption of all the unit functions and discharge of the liquid nitrogen from the process tank.
  8. When the temperature of the unit is the same as the one outside, it is possible to clean the machine.




Diagonal pieces < 100 mm
Liquid nitrogen film thickness about 5 mm
Vibration frequency 40/60 Hz
Movement breadth 0.3/15 mm
Angle inclination -2°/+4°
Contact time < 15 sec.

The plant from which we took the productivity data and that we propose as standard are:

Liquid nitrogen film thickness about 5 mm
Bulk dimension 2.000 x 1.600 x 1.300 mm
Nitrogen tank dimension 1.500 x 1.000 mm

During practical tests realized in collaboration with our customers, we obtained extremely interesting results, especially when compared with the compact dimensions of the equipment.

Liquid nitrogen film thickness about 5 mm
Apple cubes 1.000 kg/h
Lentils 720 kg/h
Mixed berries 250 kg/h
Strawberry 180 kg/h
Slices of kiwi 600 kg/h
Boiled rice 850 kg/h