How To 3D Print Food

The 3D printing industry traces its history back to the 1980’s and has continually seen significant growth. 3D printing is employed in various industries mostly for creating product models, machine parts and prototypes.

Over the years, 3D printing has become quite relevant in the food industry (although still at its infancy). If we were to give a definition of 3D food printing, we’d simply say that it involves manufacturing food products using additive manufacturing techniques.

Later in this article, we’ll go over the application of 3D printed food but first, let’s look at the process by which they are made.                 

Most Popular 3D Food-Printing Techniques

In food printing, there are different printing techniques used and there are three major factors that influence precise and accurate results. These include the materials and ingredients, process methods and post-processing methods. The ingredients used are dependent on the printing technique to be employed.

 Below are the various printing techniques used for food printing.

1. Extrusion-based printing

The ingredients used in extrusion based food printing are naturally soft. These ingredients are often soft enough to be extruded from a printhead and they have the characteristic of shape retention due to their viscous nature. Sometimes, powdered ingredients like protein are added to increase the viscosity. Solid materials however, are used by first melting before extrusion. Some of the ingredients used in extrusion based printing include jelly, mashed potatoes, cheese, puree and frosting.

The extrusion based 3D printers are used for this process.The raw materials/ingredients are fed into a syringe-like container. A 3 axis stage with a computer controlled extrusion head serves as the platform on which the food is printed. The extrusion head works by applying pressure to force the ingredients through a nozzle.The size of the  nozzle used varies depending on the type of food being extruded. The desired printing speed also affects the nozzle you decide to use.The extrusion head travels along the stage  while the food is extruded to print the desired food. 

There’s another approach to extrusion-based printing, specifically for solids, where the extrusion head heats the ingredient/material. The material is heated slightly above its melting point, then extruded to form the food which solidifies after a while. Chocolates are made using this approach because of their ability to melt and solidify quickly.

The other ingredients for extrusion based printing listed above like puree can be printed at room temperature.

Extrusion based food printers allow a wider range of materials(compared with others). But due to the soft nature of these materials, it becomes difficult to create complex food models and shapes.

2. Selective layer sintering

The ingredients used in selective layer sintering are usually in powdery form. The powdered ingredients are solidified layer by layer by heating with a laser. This process proceeds in a vertical upward way until you get the desired result. Unbonded ingredients can be recycled and further utilized in printing another food model.

This printing technique can be used for complex food models. It also allows for a variety of food textures. The limitations of this technique lies in the form of ingredients(powdered) it can work with. For this reason, selective laser sintering is applied primarily for sweets or candies production.

Other selective laser sintering ingredients include chocolate powder and  protein powder.

3. Inkjet printing

Inkjet printing ingredients comprises materials with low viscosity mainly used for surface filling. Examples include colored food ink and sauces.

The printer utilizes gravity to drop edible food ink on the food’s surface. The printhead does  not make contact with the food. This is an advantage because the food is protected from contamination.

4. Binder jetting

Binder jetting also uses powdered materials/ingredients. However, instead of using a laser as a heat source, a liquid binder is used to bond the materials together. The powdered ingredient is bound layer by layer repeatedly to produce the desired food model. 

Binder jetting printing technique is also applicable in creating complex food shapes and models, as well as a variety of food textures. It finds its limitations in the nature of the material/ingredients it works with.

5. Multi printhead and multi material

As the name implies, this printing technique enables the printing of multiple ingredients either simultaneously or consecutively. Food can be printed from several printheads printing different materials/ingredients, or from a single printhead alternating different ingredients/materials when required. The advantages of food printing using this technique includes increased productivity and efficiency as well as novel design patterns across a relatively broader nutritious range.

To make things easier for users, the most advanced 3D food printers come with preloaded recipes. Another interesting make-life-easy feature is the ability of users to design their food remotely through PCs, smart phones or any suitable smart device.

Before consumption of 3D printed foods, you'll need to verify that the foods are safe for consumption. Some 3D printed foods may actually need to be post-processed before consumption. This process is very important and must not be skipped where necessary to avoid causing harm to consumers.

The post processing methods may include baking, frying,cleaning, microwaving, etc. During this   process, some printed food may be prone to deformation especially those from extrusion based printing. Currently, additives like hydrocolloids and transglutaminase are added to the printing materials/ingredients  to enhance shape retention after post processing. Visual simulation for dough and batters has been made available with recent development, to show the actual effect  post processing will have on the food. You can get this information by adjusting certain parameters in the visual simulation.

In coming years, there should be better technology to help combat the issue of deformation as well as other problems associated with food printing.

Application of 3D Printed Food

The applications of 3D printed food are vast, ranging from customized foods to sustainability and so much more. Some of these applications are explained below

• Customized/personalized food: As with other sectors of 3D printing, you can personalize foods and make food patterns of interesting and unique designs based on your personal food requirement. You can also modify the food composition, and decide the exact amount of vitamins and other nutrients needed for say people who require a special nutritious requirement like older adults.
• Creative and innovative food design: In the food industry, food presentation is quite important. Before the advent of 3D printing in the food industry, food design was done by hand. The limitation of this was that there were some complex designs that could not be done at the time. However, chefs can now make food designs of complex shape, include brand logos or signatures to their design and much more.
• 3D Printed food in space: 3D food printing can serve astronauts outside Earth, by making a variety of delicious and  appealing  3D printed foods within reach. This helps enhance life in space and contributes to the cause of space exploration.
• Food sustainability and  Reducibility: With the world’s population on the rise, there’s the concern of running out of food resources. Hence, the need for a sustainable food source. Experts say that we might have to turn to other sources of protein and materials like insects, grass, etc. These materials could be made into powder form and 3D printed into a more appealing food with equal health benefits as conventional food. Additionally, food waste can be reduced or minimized as ingredients can be recycled to form another food model. Also, distorted fruits,vegetables and other perishables can be prevented from wasting too by converting to a form that can be 3D printed.

Limitations of 3D Food Printing

We have seen how we can apply 3D printed food and how it benefits us. While that is true, there are some drawbacks associated with this technology.

One of such which we have earlier mentioned is the range of materials available for printing. Another drawback of 3D food printing is the cost of the  equipment and consumables required.

In post processing, the deformation of the food is a concern. Since 3D food printing is still at its infancy, we can expect improvements soon.

3D Food Printers

There are two categories we'll look at; the professional printers for commercial purpose and consumer printers.

Professional printers can be used by chefs for events, restaurants and other catering services. Some examples of professional 3D food printer are:

• MMuse: The MMuse is a chocolate 3D printer. It is an extrusion-based printer that melts chocolate chips (up to 4mm in diameter) before extrusion. It is quite costly, priced at around $5700.
• Foodini: Foodini is a very popular 3D food printer developed by Natural Machines. The natural machines' foodini, can work with almost any ingredient/material. It utilizes five different cartridges(syringes) at the same time. Natural machines have pre-loaded nutritional recipes.
• byFlow Focus: Focus is an extrusion based printer used worldwide. Although it's small, it is quite powerful. Some of the main features of this printer that contributes to its popularity is that it can be controlled with wi-fi and the syringes are reusable. The reusable syringes can be filled with edible pastes.

Consumer printers are the ones that can be utilized for home use. Some of them are;

• Procusini: An extrusion based printer that can heat up to about 60°C to melt solid materials before extruding. This printer is also capable of handling small events.
• Mycusini: A chocolate 3D printer with a great design. The syringes are easy to fill.

The cartridges for both Mycusini and Procusini printers must be purchased directly from the manufacturer, Print2taste.

Conclusion

3D printing of food is already making waves in the food industry, offering several potential benefits. The process of additive manufacturing in food employs several printing techniques which include extrusion based printing, selective laser sintering, bind jetting and inkjet printing. The raw material/ingredients used varies and the process for each differs, each having its drawback and benefits. In general, while there are some notable limitations experienced in 3D food printing (which can be attributed to the fact that the industry is still at its infant stage), there are quite some benefits that make it worthwhile. Growth should however be expected in coming years