What is it about nanotechnology that attracts you?

Nanofood - of miracle pizzas and magic milk

New properties through nanotechnology

Take the new nano milk shake. You can decide later how it tastes: Depending on how hard you shake the drink, it tastes like banana or strawberry. This shake drink does not yet exist. But the researcher Manuel Marquez from the US food company "Kraft Foods" wants to turn his idea into reality with the help of nanotechnology.

Nanoparticles are particles that are even smaller than the finest dust particles. A nanometer is the millionth part of a millimeter. To be able to imagine this, a comparison helps: a nanoparticle is roughly as small as a soccer ball compared to a soccer ball as compared to the globe.

The special thing about nanoparticles is that they can turn physics and chemistry upside down: If you change structures in the nano range, brittle materials can suddenly become hard or molecules that did not match before suddenly form a connection.

Nanotechnology therefore opens up completely new avenues for development engineers. Hundreds of nanotechnology products are now on sale around the world. They are hidden in articles such as car tires, cosmetics and now also in food.

Nanocapsules serve as flavor transporters

The researchers create nanocontainers so that the milk changes its taste when shaken or the pizza changes its color. These tiny capsules are between ten and a hundred nanometers in size and mostly consist of fat molecules. They can be filled with vitamins, flavorings or colorings as desired and prepared in such a way that they only dissolve when they are exposed to certain stimuli - shaking or microwaves.

The nanocontainers are particularly interesting for so-called functional food - i.e. all those foods that are already artificially enriched with vitamins and nutrients. For example, an Australian company has launched bread baked with fish oil, the cholesterol-lowering omega-3 fatty acids of which only develop in the stomach.

Up until now it has also been difficult to fortify dairy products with calcium, because above a certain amount it clumps. Here, too, nanocontainers could help by simply packing the calcium in a capsule made of proteins.

Nanofood corporations are hoping for huge profits

Sales of functional food are increasing tremendously. So it's no wonder that all the big players in the industry have long been doing nano research. Unilever, for example, uses nanotechnology to produce ice cream that contains ten times less fat. The food company Cargill relies on beverages that are pepped up using nanotechnology. Nestlé finances nano research at the Universities of Graz and Freiburg. BASF is working on vitamins and other additives in nanoform.

The first patents have already been issued. One of the leading chocolate bar manufacturers has had chocolate protected, which does not melt as quickly even in the blazing sun. The chocolate coating contains titanium dioxide, which is also used in sunscreens. According to the company, this should be completely non-toxic.

Is nanofood healthy or dangerous?

Little research has been done to date on whether nanotechnology in the food sector is actually as harmless as the industry claims. However, since it has been scientifically proven that substances in nanoform can have different properties than in their original state, caution is advised. For example, non-toxic substances can become toxic when they are reduced in size. In addition, the extremely small nanopowder can spread in the body and possibly cause cancer.

At the Berlin Federal Institute for Risk Assessment (BfR), a project group is working on the risks of nanotechnology in the food sector. Can nanoparticles penetrate tissue layers that are not accessible to larger particles? Once they get there, how long do they stay and what are they doing there? There are still no answers to these questions.

Consumers want labeling

Some foods with nanoparticles are on the market without being specially labeled: Ketchup, for example, contains silicon dioxide, which makes it thicker, titanium dioxide can be found in salad dressing as a bleaching agent and aluminum silicates prevent powdered foods from caking. All of these products have been on the shelves for a long time and are therefore not subject to the European "Novel Food" regulation for new foods.

For a small nanotechnological change in a tried and tested recipe - for example by adding silicon dioxide to make it thicker - manufacturers do not need to submit toxicological tests. For this reason, many consumer associations are now calling for a uniform approval process and labeling obligation for nanofood - similar to those for genetically modified food.

WDR | Status: 24.01.2021, 11 p.m.