About the technology

OptiFreeze has developed a patented freezing technology, enabling fruit, vegetable, berry and herb taste, form and structure to be preserved even after freezing, storaging and thawing. This 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. By extracting natural sugars and plant proteins from, amongst others, winter wheat and cassava roots, and infusing these into fruit, vegetable, berry and herb cells, the frost protection property is transferred. The fruit, vegetable, berry or herb will then bear the cold in the same way as the grass or winter wheat.

Many fruits, vegetables, berries and herbs lose their flavour, form and structure when frozen and thawed. This is due to the cells of the living plant bursting due to the ice crystals formed during the freezing. This is particularly evident in cases of soft structure plants, for instance strawberries, but it also applies to root-crops and vegetables such as spinach and salad. By controlling the water in the cells and changing its composition, the formation of ice crystals can be controlled and the cell structures preserved intact. This technology includes vacuum technology and overpressure, as well as so-called pulsed electric fields (PEF). This process keeps the cells from bursting, hence enabling the foods to survive the freezing process whilst also retaining their flavour and appearance from before. The quality, including the taste, form and structure, can hence be preserved through the entire freezing and thawing processes. The ambition is for, for instance, thawed strawberries to look and taste like newly picked ones, and have the same texture as they did on the day they were picked. This despite having been kept in a freezer for a considerable time.

The company technology is based on a combination of very short, high-voltage pulses (so-called electroporation), pressure and vacuum impregnation Foods to be processed are soaked in a bath filled with a specific concentration of naturally occurring sugars and anti-freeze proteins, extracted from (for instance) winter wheat. No artificial substances are added. The food is then exposed to very brief high-voltage pulses. In conjunction with this, pores are formed in the plant cells, enabling the substances to enter. This effect is reversible, as the cell membrane pores will close shortly after the disappearance of the electrical field. To increase the effect, controlled pressure and vacuum sequences are used while the foods are being soaked.