Researchers develop a milk-based 3D printing method

Researchers at SUTD managed to develop a 3D printing method to print milk structures

Food-based materials and 3D printing are not strangers. We have mentioned them a couple of times before. This time, a team of researchers at the Singapore University of Technology and Design (SUTD) 3D printed milk products at room temperature and with no additives. To achieve it, the team used a Direct Ink Writing (DIW) 3D printing method with a simple milk ink formulation.

Direct Ink Writing is an AM (Additive Manufacturing) extrusion method that is mostly used for meso and microscale structures. In DIW, the liquid-phase ink is dispensed out of small nozzles under controlled floor rates. Then, it is deposited along a digitally defined path to fabricate 3D structures by a layer at a time.

A setup for direct ink writing (DIW) 3D printing for cold extrusion. (A) A photograph of a DIW printer used in the experiment. (B) A schematic illustration of DIW of mesh structure with milk ink onto a glass substrate. Source: RSC Advances.

Why using an Additive Manufacturing method such as Direct Ink Writing?

Rich in protein and calcium, milk is hardly compatible with 3D printing processes that require high temperatures. Its composition would simply deteriorate too much as the temperature increases. Therefore, the researchers relied on a cold extrusion process. Michinao Hashimoto, a lead researcher from this study, explains:

COLD EXTRUSION DOES NOT COMPROMISE HEAT-SENSITIVE NUTRIENTS AND YET OFFERS GREAT POTENTIAL FOR 3D PRINTING OF AESTHETICALLY PLEASING AND NUTRITIONALLY CONTROLLED FOODS. AND ADAPTED TO INDIVIDUAL NEEDS”
Michinao Hashimoto – Lead researcher from the “3D printing of milk-based product” Study.

Using water and milk powder, scientists designed a special ink with very specific rheological properties.

This is because cold extrusion often requires rheology modifiers or additives to stabilize the printed structures. A particularly complex step as reported by the researchers. The ink must have a low enough viscosity rate at a high shear rate to allow the ink to extrude through the nozzle. According to the researchers, this milk powder can be 3D printed in the form of a rigid envelope that could be filled with blueberries, chocolate, or maple syrup.

3D printing of milk-based product – Samples

3D-printed multi-food models. (A) Schematic illustration of multi-material DIW 3D printing. (B) 3D structure of a couch printed with milk and chocolate inks at different layers. (C) 3D printed cone containing liquid chocolate syrup as an internal filling. (D) 3D printed cube with four compartments containing liquid blueberry syrup, liquid chocolate syrup, milk cream, maple syrup as internal fillings all scale bar: 5 mm). Source: RSC Advances. — 3D-printed multi-food models. Source: RSC Advances.

On the printing side as such, the team explains that speed depends of course on the size of the machine. So far they have tested small parts that only took 5 minutes to 3D print. In particular, they designed small canapes made of milk and chocolate by overlaying ingredients. Lee Cheng Pau, one of the study researchers, concludes:

THIS SIMPLE BUT INNOVATIVE METHOD CAN BE USED FOR THE FORMULATION OF A VARIETY OF NUTRITIOUS FOODS, INCLUDING THOSE SERVED TO PATIENTS IN HOSPITALS FOR THEIR SPECIAL DIETETIC NEEDS.”
LEE CHENG PAU

You can find more information about the project here.

What do you think of 3D milk printing? Leave your comments below!