Researchers from Nanyang Technological University, Singapore (NTU Singapore), Singapore University of Technology and Design (SUTD) and Khoo Teck Puat Hospital (KTPH) have developed a new way to create "food inks" from fresh and frozen vegetables, that preserves their nutrition and flavour better than existing methods.
Food inks are usually made from pureed foods in liquid or semi-solid form, then 3D-printed by extrusion from a nozzle, and assembled layer by layer.
Pureed foods are usually served to patients suffering from swallowing difficulties known as dysphagia. To present the food in a more visually appetising way, healthcare professionals have used silicone moulds to shape pureed foods, which is labour and time intensive, and requires storage.
While 3D food printing means food can be easily produced in a desired shape and texture in a shorter time, the dehydrated food and freeze-dried powders used as food inks usually contain a high percentage of food additives such as hydrocolloids (HCs) to stabilise the ink and enable a smoother printing process. High concentration of HCs usually changes the taste, texture and aroma of the printed food, making it unappetising to patients with dysphagia. This may lead to reduced food consumption and malnutrition among patients.
To overcome this challenge, the research team explored various combinations of fresh and frozen vegetables to make the food inks stable.
Not only were they able to better preserve the nutrition of the printed food, they also made it more palatable. This new method of making food inks should lead to increased meal consumption by patients, contributing positively to their physical health and mental state of mind.
Additionally, the team discovered that vegetables could be broadly classified into three categories with each requiring a different hydrocolloid treatment in order to become printable. For instance, garden pea, carrot and bok choy were chosen as representatives in each category, requiring no HCs, one type of HC and two types of HCs, respectively (refer to images).
Prof Yi Zhang, the principal investigator from the NTU team said, "Our technology helps to provide dysphagic patients with adequate nutrient-rich and safe diets. Their feeding is more dignified, enabling them to socialise and consume meals that look, feel and taste like regular food. Our method of 3D printing fresh vegetables can be used easily in hospitals, nursing homes, day care centres for the ageing population with dysphagia and other swallowing disorders. Our research is also another step forward in digital gastronomy, where we can cater to specific requirements prescribed by dieticians, such as nutrition customisation and visual appeal."
Prof Chua Chee Kai, corresponding author and the Head of Pillar, Engineering Product Development at SUTD, added: "The next frontier of additive manufacturing is 3D food printing. As the 3D food printing landscape is increasingly evolving, we are excited to continue pushing the boundaries of this industry to find innovative solutions for global issues such as food security and sustainability."
Gladys Wong, co-principal investigator and Senior Principal Dietitian from KTPH said: "3D Food Printing is more than a novelty. I believe it will be a viable approach in the near future in providing sustenance and nourishment to our increasing ageing population. Our frail, elderly patients as well as those with swallowing difficulties will be able to enjoy a visually presentable and pleasurable dining experience even with a restrictive diet of smooth pureed dishes."
Singapore University of Technology and Design
Khoo Teck Puat Hospital
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Nanyang Technological University
About Singapore University of Technology and Design
The Singapore University of Technology and Design (SUTD) is Singapore's fourth public university, and one of the first universities in the world to incorporate the art and science of design and technology into a transdisciplinary, human-centric curriculum. SUTD seeks to advance knowledge and nurture technically-grounded leaders and innovators to serve societal needs. SUTD also recently topped a list of emerging engineering schools in the world in a study conducted by MIT.
A research-intensive university, SUTD is distinguished by its unique East and West academic programmes which incorporate elements of innovation, entrepreneurship, design thinking and local and international industry collaborations. SUTD's key focus areas are Healthcare, Cities and Aviation, supported by capabilities in Artificial Intelligence/Data Science and Digital Manufacturing. Multiple post-graduate opportunities are available. In addition, skill-based professional education and training courses are also available at SUTD Academy.
About Nanyang Technological University, Singapore
A research-intensive public university, Nanyang Technological University, Singapore (NTU Singapore) has 33,000 undergraduate and postgraduate students in the Engineering, Business, Science, Humanities, Arts, & Social Sciences, and Graduate colleges. It also has a medical school, the Lee Kong Chian School of Medicine, established jointly with Imperial College London.
NTU is also home to world-renowned autonomous institutes - the National Institute of Education, S Rajaratnam School of International Studies, Earth Observatory of Singapore, and Singapore Centre for Environmental Life Sciences Engineering - and various leading research centres such as the Nanyang Environment & Water Research Institute (NEWRI) and Energy Research Institute @ NTU (ERI@N).
Ranked amongst the world's top universities by QS, NTU has also been named the world's top young university for the last seven years. The University's main campus is frequently listed among the Top 15 most beautiful university campuses in the world and it has 57 Green Mark-certified (equivalent to LEED-certified) building projects, of which 95% are certified Green Mark Platinum. Apart from its main campus, NTU also has a campus in Singapore's healthcare district.
Under the NTU Smart Campus vision, the University harnesses the power of digital technology and tech-enabled solutions to support better learning and living experiences, the discovery of new knowledge, and the sustainability of resources.
For more information, visit http://www.ntu.edu.sg
About Khoo Teck Puat Hospital
Khoo Teck Puat Hospital (KTPH) is a 795-bed general and acute care hospital, opened in June 2010. Serving more than 550,000 people living in the northern sector of Singapore, KTPH combines medical expertise with high standards of personalised care, set within a healing environment, to provide care that is good enough for our own loved ones. From intuitive wayfinding to logical clustering of services, KTPH's design is focused on providing a hassle-free experience for patients. The hospital has been designed with patients' comfort in mind. Since its opening, the building has garnered numerous awards for its green and energy efficient design. Patients can enjoy comfortable accommodation in different categories of wards with views of greenery and naturally cool air from improved ventilation. KTPH also provides a wide range of outpatient specialist services.