How are 3D printed foods edible?

Food from the 3D printer

The top priority is hygiene

Food is her passion - which is why Melanie Senger and her colleagues experimented a lot. Somehow, thought the team at the Institute for Food Technology at the Weihenstephan-Triesdorf University of Applied Sciences, one must be able to change the consistency of the food so that it can be brought into any shape.

They dreamed of a small device that would do just that. "We would have loved to buy something like that and then let our creativity run free with it, but that just didn't exist," says Melanie Senger. So she worked on it herself.

They exchanged the print head on a commercially available 3D printer and replaced it with an extruder for paste that they had designed themselves and produced using 3D printing. Then they took cream cheese, dough, liver pate and tea sausage, chocolate, caramel and marzipan as well as pureed vegetables and fruit - and tried, tried, tried.

"It worked with a surprising number of foods, but we kept noticing that one and the same product worked wonderfully one time and then not at all," says Senger.

The young research team suspected natural fluctuations in their starting products. For example, if the amount of shell of the almonds in the marzipan varies, the consistency of the mixture also changes. However, this must remain constant. If the marzipan is too firm, only crumbs come out of the printer, if it is too liquid, the object will run apart.

The students developed a standardization for individual foods that they can deliver to customers today. The concept is well received: The company Print2Taste, founded two years ago as a spin-off from the university, is successful.

The printhead is now made of metal and the cartridge containing the food to be printed is inserted into it. The paste never comes into contact with the printer - after all, this is where food is produced, and hygiene is the top priority. The nozzle that injects mashed potatoes and hot chocolate into molds is food certified.

Snack at the push of a button

The particular challenge facing the food printer is to find the right mix of the right temperature and the right printing speed. While liver sausage, for example, is best processed at room temperature, chocolate has to be melted.

However, it must not be too hot, otherwise it will be too liquid - and the pressure strand will tear. At the same time, the nozzle must move so slowly that the chocolate mass has time to harden before the printer sprays the next layer.

Researchers at Columbia University in the United States of America have presented a 3D printer that can print healthy snacks - made from polenta, for example. They say: There will soon be such a device in every household - healthy meals will be possible at the push of a button.

Pour in powder, paste, gel or liquid, enter the desired snack and wait until the food is printed. The printer is not yet ready for the market and nothing is known about the price either.

Wedding couples to nibble

The Bavarian food printers have a different clientele: upscale gastronomy and catering. "A personalized greeting from the kitchen is wonderful to print," says Melanie Senger.

The printing time depends on the size of the object. A small company logo, for example, can be created in one to two minutes. Figures five centimeters high took longer - depending on the material. A 15 centimeter wide Neuschwanstein Castle made of marzipan takes five and a half hours.

Senger can also imagine a 3D printer for food in a classic pastry shop: "As a customer, for example, you write a greeting by hand on the tablet and receive it a few minutes later as a decoration on the birthday cake."

This also works with photos and drawings. According to Senger, figures of wedding couples and anniversaries are also in great demand.

For astronauts: pizza from the printer

When people hear that the food comes from the duiker, many are skeptical. "To most, that sounds like something unnatural with a lot of chemistry," says Senger. But only products of natural origin are processed. "In principle, the printer is a very precise automatic piping bag."

The inventor Anjan Contractor originally developed a printer for the space agency NASA that turns dough, tomato sauce and cheese into a pizza. Cinnamon rolls and cupcakes are also no problem for the printer.

Three-dimensional chocolate printing shops are also very popular. Chocolate selfies, personalized figures from the sweets or architectural chocolate works are now available in some pastry shops and caf├ęs that want to offer their customers something extraordinary.