New hydrogels have been created from modified starch which can then be used as 'ink' to produce food through 3D printing technology.
Scientists are already capable of producing 3D printed food, with the ability to change the product to suit the consumer preferences regarding aspects like taste, texture, cost, convenience and nutrition. In the near future, it will be possible to produce food with personalized shapes, texture, flavours, and colours.
Researchers at the University of São Paulo’s Luiz de Queiroz College of Agriculture (ESALQ-USP) in Brazil, partnering with colleagues in France at Nantes Atlantic College of Vetinary Medicine, Food Science and Engineering (Oniris) and the National Institute for Research on Agriculture, Food and Environment (INRAE), have made strides toward achieving this goal. They are developing hydrogels based on modified starch for use as “ink” in 3D printing of foods.
The journal Food Research International published the results of the project, supported by FAPESP (São Paulo Research Foundation). “In the past few years we’ve developed different technologies to modify starch and obtain gels with ideal characteristics for use as ‘ink’ to produce food by 3D printing,” Pedro Esteves Duarte Augusto, a professor at ESALQ-USP and principal investigator for the project, told Agência FAPESP.
The researchers based the first gels on cassava starch. They developed the method used to modify the structure and properties of the starch with ozone during a previous project also supported by FAPESP
They produced ozone by applying an electrical discharge to oxygen, bubbled the gas in a container with a mixture of water and cassava starch is suspension, and dried the mixture by extracting the water. The result was modified starch.
By varying aspects of the process such as ozone concentration, temperature and time, they were able to create gels with different properties concerning texture and consistency for the use of 3D printing.
“Control of the conditions enabled us to obtain weaker gels for other applications and firmer gels that are ideal for 3D printing because they retain the shape of the printed structure without flowing or losing moisture,” Augusto said.
Researchers have also developed a modification of starch which produces gels that display optimal printability, defined as the ability to make a 3D object by additive manufacturing (layer-by-layer deposition) and to maintain its structure once printed. Dry heat treatment is also extended to the textural possibilities of printed samples based on wheat starch hydrogels.
“We obtained good results with both methods. They’re simple, cheap and easy to implement of an industrial scale,” Augusto said.
Oniris and INRAE in France printed samples of gel based on cassava and wheat starch in a project funded by the Pays de la Loire regional innovation agency.
Gels based on modified cassava and wheat starch can be used to print other things apart from food, such as biomedical products including drug capsules and nutraceuticals – food designed with health and nourishment in mind.
“We’ve demonstrated the feasibility of food production by 3D printing and fabrication of tailormade ingredients. Now we plan to extend the applications and test other raw materials,” Augusto said.
The development of hydrogels is a massive step in the right direction for the development of ‘ink’ in 3D printed foods. The development of 3D printed foods will mean that food can be made from scratch; its texture, taste and nutrients can be controlled and altered for personal preference creating a new age of food production.
By Rowenna Hoskin | Science Editor