New methods of producing modified starch, or “ink” for 3D food printing, could make this process possible on a massive scale.
A group of scientists believe they have come one step closer to the massive industrialization of 3D-printed food.
Team from the University of São Paulo Luiz de Queiroz College of Agriculture (ESALQ-USP) in Brazil, in collaboration with French colleagues from Nantes Atlantic College of Veterinary Medicine, Food Science and Engineering (Oniris) and the National Institute for Research on Agriculture, Food and the environment (INRAE) have developed hydrogels that act like “ink”.
The latest results of the project, supported by FAPESP (São Paulo Research Foundation), have been published in the Food Research International journal. “Over the past few years, we have developed various technologies to modify starch to obtain gels with ideal properties for use as” ink “in food production through 3D printing, said Pedro Esteves Duarte Augusto, professor at ESALQ-USP and principal investigator of the project, told FAPESP.
The first gels produced by scientists were based on cassava starch, and a method of starch modification was also developed by the research team.
According to the group, ozone was produced by electric discharge to oxygen, and then the gas was passed in a container with a mixture of water and cassava starch in suspension, and then dried (by removing the water). The result was modified starch.
By varying aspects of the process (such as ozone concentration, temperature and time), scientists managed to obtain gels with different properties to find the right consistency for use in 3D printing.
“Controlling the conditions has allowed us to produce weaker gels for other applications and harder gels that are ideal for 3D printing as they retain the shape of the printed structure without sagging or losing moisture,” said Augusto.
In the last two years, in addition to ozone, scientists have developed another method of starch modification. This includes dry heating cassava and wheat starch in an oven while controlling temperature and time.
Thanks to the new method, they also obtained gels based on modified starch, showing optimal printability, i.e. gels that were able to create a 3D object that retained its structure after printing. The research team concluded that dry heat treatment also expanded the textural capabilities of printed samples based on wheat starch hydrogels.
“We obtained good results with both methods. They are simple, cheap and easy to implement on an industrial scale, ”Augusto said.
In collaboration with French scientists, ESALQ-USP researcher Bianca Chieregato Maniglia conducted studies at Oniris and INRAE using ozone and dry heating techniques developed in Brazil to produce gels based on modified cassava and wheat starch for 3D printing.
“The combined experience of all the scientists involved in the project has enabled us to obtain gels with better printability, resulting in foods with better shape, definition and texture, which are essential parameters for product acceptance,” said Maniglia.
The ESALQ-USP group said it now plans to explore other modification methods and production sources for 3D food printing gels. The university recently purchased a 3D printer, which it will use to produce structures developed using new gels.
The research group added that modified cassava and wheat starch gels could also be used to print other things, such as biomedical products, including medicine capsules and nutraceuticals.
“We have proven the feasibility of food production by 3D printing and manufacturing custom ingredients. Now we plan to extend the applications and test other raw materials, ”Augusto said.