Researchers from Nanyang Technological University in Singapore (NTU Singapore), the Singapore University of Technology and Design (SUTD) and the Khoo Teck Puat Hospital (KTPH) have jointly found a new way to make “food inks” from fresh and frozen vegetables. The researchers say the food inks preserve the nutrition and taste of fresh and frozen vegetables better than existing methods.

ON Food ink is typically made from pureed foods in liquid or semi-solid form that are 3D printed by extrusion from a nozzle and put together layer by layer. In a medical setting, pureed foods are often served to those with difficulty swallowing. In the healthcare sector, silicone molds are widely used to shape pureed foods so that they look more appetizing to those who eat them.

By 3D printing the food, it can be produced in the desired shape and texture in less time. Currently, dehydrated foods and freeze-dried powders are used as food inks and typically contain a high percentage of food additives such as hydrocolloids (HCs) to stabilize the ink and make the printing process smoother. The catch is that high concentrations of HCs typically alter the taste, texture, and aroma of printed foods and make them unpleasant.

The researchers examined combinations of fresh and frozen vegetables to make food inks stable. This enabled them to better get the nourishment of the printed foods and make them taste better. The hope is that the manufacture of food inks will lead to increased consumption by patients and improve their physical and mental health. The project’s researchers roughly classified vegetables into three categories, and each category required a different hydrocolloid treatment to become printable.

The researchers used garden peas, carrots and bok choy as representatives for each category in the project. This vegetable did not require any HC, one HC type or two HC types.