When acoustic waves freeze food

Some foods can be wonderfully deep-frozen - many types of vegetables or rolls of all kinds, for example. Others, however, are very sensitive, because after defrosting they do not look and taste as good as they used to.

The reason for this is that the low temperatures cause the liquid in and between the cells of the food to freeze. The slower they freeze, the larger ice crystals form, which affect the cell structure. The more sensitive the food, the more the cell structure is attacked. This is why raspberries, for example, do not look very nice after thawing.

However, there is a method that can solve these problems: Acoustic Extra Freezing (AEF) - a method that is marketed in Germany by the company of the same name, AEF Deutschland GmbH. This method freezes food particularly gently and up to 25 percent faster than the traditional method. Due to the acoustic resonance, the ice crystals are reduced in size to nano ice crystals. They are so small that they do not damage the cell walls. The result is food that looks exactly the same after thawing as before. And that's not all: thanks to AEF technology, up to 97 percent of the nutrients are retained, the food can be stored for longer, and the taste does not change. After freezing with AEF technology, the vacuum-packed food, which may already have been processed, is then stored at -18°C as normal. The perfect conditions for healthy, long-life food, even in the premium sector.

AEF Germany is the exclusive partner of the Acoustic Extra Freezing Group from Helsinki. The Finns are currently in the process of going one step further with the technology: They are working on freezing blood to preserve it. This would be a huge step, as blood currently only has a shelf life of 42 days.