The food sector has been developing several new technologies and defining new borders for food processing by delivering a product that suits a particular consumer’s criteria of taste, cost, convenience, and nutrition. The worlds of food science and microtechnology have collided, enabling modern 3D printing technology to transform our ability to prepare and consume foods. Even though foods are characterized by having complex systems with wide variations in physicochemical properties, researchers worldwide are currently working on studying and improving the application of 3D printing to various types of food products such as chocolate, processed cheese, meat, and even some fruits and vegetables [1,2].
The process of printing food is similar to regular printing, but instead of ink, the printer must be adapted to work with nourishments, including sugar, starches, and proteins. Briefly, the process of using a 3D bioprinter to print food involves carefully layering tiny semi-liquefied food particles on top of each other to create novel processed foods [2,3].
Using this technique to obtain processed food has several advantages: meal composition adapted to the individual diet, ease of transportation even to the most remote corners of the world or into space, and longer shelf life [3]. In 2006, NASA began researching 3D-printed food. In 2013, the NASA Advanced Food Program, aiming to promote better nutrition for astronauts’ team in more extended missions, developed the Chef3D. This bioprinter could 3D print a pizza that only had to be placed into the oven [4]!
Figure 1: 3D printed a pizza developed by the NASA Advanced Food Program [4].
The 3D printing of food follows the principle of a Solid Free-Form (SFF) method. The Fused Deposition Modeling (FDM) is the primary 3D printing method that can be used for printing food, among other methods such as the Stereolithography Lasing (SL) and the Selective Laser Sintering (SLS). In essence, the FDM approach is based on depositing purees, gels, and doughs directly, in layers, without any structuring agent to support their structures. The ingredients are mixed and stored in different containers. For example, a syringe can be connected to one or two nozzles and deliver the ingredients by pushing them onto a platform using an electric motor. This system, called a dual-feed extruder, pushes two different materials with different colors from the nozzle to generate a third color by adjusting the mixing ratio controlled by a colormix generator [5].
Figure 2: The FDM and the SLS bioprinting methods [6].
At Cornell University, a group of researchers has made the first multi-material 3D printer available to the public. The 3D printer was first based on a single head extrusion system which was improved later on and extended up to eight extrusion heads enabling printing of diverse materials from epoxy and silicone to chocolate and cheese. The team worked further on the concept of chocolate printing, focusing on the technological issues of chocolate tempering, deposition precision, and process control, which led to the development of the world's first chocolate printer. They are implementing two deposition heads into the current machine by adding various materials to the chocolate, such as caramel, nougat, and toffee. The device’s success can pave the way for many other pioneering engineering techniques to migrate into the food industry [7,8].
The global population is constantly increasing, which naturally results in the growing demand for food. Ingredients extracted from algae, fungi, seaweed, lupine, and waste from the current agricultural and food production can be an alternative as printing materials in the future. Using other advanced technologies makes these food nutrients more stable and absorbable in the human body, scaling them to a greater extent. Furthermore, 3D printed meat can address the high emission rates of methane from agriculture by providing high-quality proteins without increasing stress on arable land or continually depleting the oceans [6, 9].
REFERENCES
1. Dankar, I., Haddarah, A., Omar, F. E. L., Sepulcre, F. & Pujolà, M. 3D printing technology: The new era for food customization and elaboration. Trends in Food Science & Technology vol. 75 231–242 (2018).
2. Lin, C. 3D Food Printing: A Taste of the Future. Journal of Food Science Education vol. 14 86–87 (2015).
4. A guide to 3D Printed Food - revolution in the kitchen? - 3Dnatives. https://www.3dnatives.com/en/3d-printing-food-a-new-revolution-in-cooking/ (2019).
5. Yang, F., Zhang, M. & Bhandari, B. Recent development in 3D food printing. Critical Reviews in Food Science and Nutrition vol. 57 3145–3153 (2017).
6. Sun, J., Zhou, W., Huang, D., Fuh, J. Y. H. & Hong, G. S. An Overview of 3D Printing Technologies for Food Fabrication. Food and Bioprocess Technology vol. 8 1605–1615 (2015).
7. Lille, M., Nurmela, A., Nordlund, E., Metsä-Kortelainen, S. & Sozer, N. Applicability of protein and fiber-rich food materials in extrusion-based 3D printing. Journal of Food Engineering vol. 220 20–27 (2018).
9. Gorkin, R. & Dodds, S. The ultimate iron chef – when 3D printers invade the kitchen. The Conversation (2013).