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Customised 3D printed meals on demand

13 Apr 2022

Lianhe Zaobao, 13 Apr 2022, 3D食品打印 客制餐食需求​ (translation)
 
Printing the food that you want to eat like printing a document, may seem like a fantasy, but current 3D printing technology is setting off a food revolution, and Singapore is at the centre of this revolution; we may not be far from the future where we could be eating printed food.
 
Professor Chua Chee Kai, Head of the Engineering Product Development Pillar at the Singapore University of Technology and Design (SUTD), has been researching 3D printing technology for 32 years. He has been focusing on food printing technology for the past seven years and has developed a prototype food printer, which he plans to put on the market soon.
 
In an exclusive interview with Lianhe Zaobao, Prof Chua said: “The most advanced technology in the aviation industry is already using 3D-printed nozzles in jet engines, which shows that this technology is very safe. 3D-printed houses can also be seen in the construction industry and they are safe to live in. In contrast, 3D food printing technology is lagging behind other industries. There is huge potential if the technology in this area can be improved.”
 
According to a recent market research firm Vantage, the 3D food printing market is huge and is estimated to grow from US$76.9 million (approximately S$100 million) in 2021 to US$870 million (approximately S$1.2 billion) in 2028, with a compound annual growth rate of 49.9%. North America is expected to be the largest market for 3D food printing.
 
Prof Chua explained 3D food printing technology in terms of volume pixel or voxel. Voxel is the smallest unit of three-dimensional space. The concept is similar to bricks. If the bricks (voxels) are stacked, a three-dimensional structure can be built. He said: “In food printing, I can decide what ingredients are used for voxels, where they are in the printed food, etc., to create unique foods with different tastes and textures.”
 
Assisting patients with dysphagia to eat 
Gladys Wong, a senior dietitian at Khoo Teck Puat Hospital, saw the potential of 3D food printing a few years ago and believes that this technology can help elderly patients with dysphagia to eat. She explained that older patients with dysphagia or dementia should only eat puréed foods that are not too thick or hard for them to swallow. However, puréed foods are often unsightly, causing patients to refuse consumption or not eat much, resulting in problems such as weight loss or nutritional deficiencies. In addition, hospital staff must manually prepare these purées; the dietician and team will also have to review each meal to ensure that the food is safe and of a consistent texture, which is time-consuming and labour-intensive.
 
Gladys contacted Prof Chua in 2015, and the two decided to research on how to use 3D printing technology to print nutritious and attractive food for elderly dysphagia patients. She said: “3D food printing technology can remove human error and repeatedly print food with a consistent texture that is easy for patients to swallow. In addition, the food can be printed in various shapes, which looks more attractive and appetising, resulting in patients willingly ingesting the food and receiving the required nutrients.” The research team has printed pandan shredded coconut rolls and chwee kueh, and hopes to print the more complex fried kway teow in future.
 
In addition, 3D food printing allows for customising nutritional formulas to suit different people's health needs or preferences. For example, Gladys said, the 3D printer can use artificial intelligence to add the required vitamins or nutrients to the food for different patients.
 
Prof Chua said: "People like bespoke things and are willing to pay more for them. For example, many people like customised bags, shoes, furniture, etc. You can use the printer to make your own unique food, and if it tastes good, you can even make money selling it online.”
 
Alleviating global food shortages 
The United Nations predicts that the global population will continue to grow in the next few decades, reaching 8.5 billion people by 2030. This means that the food supply shortage problem will be more severe in the future. 3D food printing could provide a solution to this problem by extracting the required nutrients from the parts of food that humans currently do not eat or have discarded, and then printing new food. The SUTD research team has previously printed food from food waste such as orange peel, okara and jackfruit seeds, etc.
 
Gladys said: “People are now focusing on sustainable food supply. Most people don't eat insects, but they are rich in protein and other nutrients. Through 3D food printing, I can grind insects into powder, mix with printing materials and print them into meat. The taste is exactly the same as real meat, people will not be able to tell the difference, and will even eat it with relish.”
 
The challenges of printing food 
The future for 3D food printing technology is bright, but there are still some technical challenges to overcome, such as maintaining the shape of the printed food. Prof Chua said: “In all types of 3D printing, the ingredients pose the biggest difficulty, as not all ingredients are easy to print. Some ingredients may crack or collapse easily after printing. For example, I once printed chwee kueh, but it disintegrated and collapsed after a while.”
 
To maintain the shape of 3D printed food, researchers often add hydrocolloids. Prof Chua said: “Hydrocolloids are widely used in the food industry and are safe to eat. The problem lies in printing recipes. We don't know which type of hydrocolloid is suitable for which type of food/ingredient, so we have to continuously spend time to experiment.”
 
Another challenge is the cost and speed of the printer. 3D food printing has low efficiency and relatively high cost, which limits batch and large-scale production. It has many disadvantages compared with regular food production methods. “Current 3D printers are very slow and can print delicate and small food items suitable for the home or restaurants, but it takes too long to print food required by hospital patients,” said Gladys. However, she believes that this problem will be solved sooner or later. “Just like 20 years ago when everyone used pagers, no one thought that one day there would be smartphones. There will be continuous technology advancements.”
 
Research and development of high-efficiency printer for the market 
Prof Chua’s team used a 3D food printer from a well-known brand during the research process, but faced many limitations, such as slow printing speed, no heating function and even the inability to support the 3D STL graphics file format commonly used in the industry. Thus, he realised that only by developing his own 3D food printer can he improve efficiency, reduce costs and popularise the technology.
 
Due to the trade secrets involved, Prof Chua was unwilling to share more details about the prototype new printer, except that it currently has the fastest printing speed in the market. “We pushed the limits of extrusion printing technology. It took about four hours to print three food items with a volume of about 250 ml. The key technology was the nozzle – how to make it print quickly without compromising on the quality of the food.”
 
As for the price of printed food, Prof Chua believes that it cannot be set too high. “How much are consumers willing to pay to eat printed food? We cannot price it a lot higher than existing food. Our goal is for consumers to just pay a little more to enjoy better-looking, tastier and better-textured printed food.”
 
Earlier this year, Prof Chua started planning to set up a start-up company, Digital Gastronomy, to bring the printers to market. He said: “The current stage is to turn the prototype into a commercial product. An estimated investment of $3 million is required to develop the hardware, recipes and printing material. If I can find investors who believe in us, I am sure that it can be mass produced and launched in the market within a year, becoming a leader in this technology.”
 
In charge of fundraising and business expansion is Victoria Tan, another founder of Digital Gastronomy. She said: “SUTD has agreed to provide $125,000 in funding for us to start a six-month trial. We have approached some elder care homes, hoping to let the elderly try printed food and garner their feedback. After which, the team will improve on the product, and hopefully raise more funds to proceed with the market launch.”
 
When asked about the safety of printing food, Prof Chua replied: “Our team has food safety experts who measured the bacteria count in the food before and after printing, and found that there was no change, which means the printer did not bring in more bacteria.”
 
Victoria said: “3D food printing technology is very new, and there are currently no relevant food safety regulations in this area locally. I think it is very important to be open and transparent. In addition to letting consumers know what printing materials are used, the appearance of the printer will also be transparent, so that people can see the entire printing process.”
 
Prof Chua is optimistic about the future, “Food printers will become affordable, and simpler to operate. Various food printing ink cartridges will be available in the market; the concept is similar to the current capsule coffee machine.”
 
Gladys’ dreams are even bigger. She hopes food printing machines will become like the vending machines stationed at the void decks of HDB flats. “Elderly patients need only to scan their ID cards in the future, and the printer will print out meals tailored to their health needs. This will save them the trouble of going to the supermarket to buy ingredients for cooking at home, and the medical social worker will also be notified that the elderly has eaten regularly and is healthy.”