OptiFreeze > Technology


OptiFreeze owns a patented technology that enhances taste, shape and texture of fruit and vegetables throughout the freezing and de-freezing (thawing) process. OptiFreeze has furthermore developed a method that can improve shelf life of fresh cut fruit and vegetables. Also the shelf life of flower cuttings can be significantly improved. The same technology can be used to dry herbs, while enhancing taste, smell and colour. The technology provides new business opportunities for food processors and distributors all around the world. The cryoprotectants used in the process regenerate cells, which enhances the taste, shape, texture and shelf life.

Combining Vacuum Impregnation and Pulsed Electric Field

The technology is based on the same principle which allows certain plants, for instance winter wheat, to bear frost and remain green, even after cold winter days. Natural sugars and anti-freeze proteins are extracted via natural or enzymatic methods from plants such as winter wheat and cassava roots. These compounds are infused into fruits and vegetables cells, and by this the frost protection property is transferred.

The fruit and vegetable will bear the cold in the same way as the grass or winter wheat. The method for cell protection is based on the novel and unique combination of Vacuum Impregnation (VI) and Pulsed Electric Field (PEF).

Winter wheat a cold winter day

The vacuum impregnation process

Vacuum impregnation works as follows: First, air is evacuated from the product's extracellular space by lowering the pressure. The product is immersed in a solution containing natural cryoprotectants during the treatment or while the pressure is at the lowest level inside the treatment chamber.Lastly, the pressure will increase to atmospheric pressure and the solution then enters the extracellular space in the product.

The PEF process

After vacuum impregnation, the product is exposed to very short high-voltage electrical pulses, which create pores in the cell membranes allowing the sugar to enter on an intracellular level. As soon as the electrical field is withdrawn, the cell membranes reseal themselves.