By Abdullah Bareen1 and Vithu Prabha2*

The taste and appreciation of food being typically subjective, the customization of food is important. Fabrication of food by precise printing of food mix is widely recognized. Advancement in digital technologies such as multidimensional food printing has enabled food making with definite composition and microstructure. Food products are rapidly evolving; therefore, all professionals in the food manufacturing field need to follow up on the latest trends being the need of the hour.

3D printing is a digitalized manufacturing method in which the product is built layer-by-layer suited for creating customized food with complex geometries, tailored texture and nutritional content. The layers are bonded together either by phase transitions or chemical reactions. This technique is also known as Additive Manufacturing (AM).

The concept of 4D printing is ascribed to the extension of 3D printing with the addition of  time dimension. Here, the objects are designed with continuous layers of stimuli-responsive composite materials, which can alter shapes once removed after the 3D printing process. The stimuli for this physical (shape or colour) or chemical change in the state over time can be from the natural environment or through human intervention. Figure 1 compares the 3D and 4D food printing methods.

Importance of digital food printing

Food researchers emphasize food customization concerning health aspects. The consumers are self-aware of their nutritional requirements demanding healthier choices. Besides, the issue of food wastage in food sector is also growing. A remedy to all this relies on ‘on-demand manufacturing’ or ‘tailored production’ of food.

Food quality attributes to be considered by any food manufacturer is appearance, composition and nutrition. In food printing methods, a broad category of ingredients including fruits and vegetables, and their by-products can be used, which is unlike the conventional methods such as extrusion. Further, in extrusion, the quality of the end product quality is highly dependent on temperature, pressure and shear. A few of the benefits of 3D, 4D food printing methods are presented in Figure 2.

Figure 1. Comparison of 3D and 4D food printing methods

Figure 2. Benefits of 3D, 4D food printing methods

3D, 4Dfood printing process

The 3D printing technique is accepted widely for its diverse applications in allied fields. In the food sector food printing allows users to fabricate foods with customized shapes, color, flavor, and nutritional needs. 3D food printing process (shown in Figure 3) contribute to sensorial profile and has a decisive effect on the mechanical properties of the food. Also, one can manipulate the fabrication process to meet customer expectation with the digital control over the material feeding system. However, optimizing the working parameters in 3D printing process (given in Table 1) is a crucial to yield foods that stand out as quality parameters to conventional foods.

Figure 3. Schematic flow diagram of the typical 3D printing process

Table 1. Working parameters in 3D food printing process

Characteristics

Parameters

Machine

Printing speed; layer height; nozzle diameter

Model

Shape dimension; number of layers

Feed material

Composition; rheology

 

The distribution of multiple materials in the 3D model is carried out by mathematical modelling. According to the American Society for Testing and Materials (ASTM), methods successfully used for food printing are given in Table 2.

Table 2. Additive manufacturing methods for 3D, 4D printing

AM method

Composite materials

Features

Material extrusion (ME) 

Gel, molten material

Supports a large array of foods

Material jetting (MJ)

Powders + liquids

Versatile shape fabrication with high resolution and accuracy

Binder jetting (BJ)

Powders + liquids or molten materials

Support structures are included in fabrication

Powder bed fusion (PBF)

Powders

Apposite for complex food items

4D food printing fabricate dynamic structures with adjustable shapes, properties, or functionality. This capability mainly relies on an appropriate combination of smart materials in three-dimensional space. The major considerations in the 4D food printing process are the prediction of shape-shifting behavior as a function of time and self-assembly operation of the structure.

 3D, 4D food printing equipment

Several 3D printing models are available worldwide to accomplish 3D, 4D printing (few of them are presented in Table 3). In general, the printers are capable of printing customized products like pizza, pasta, chocolate, cookies and sugar cubes. Figure 4, shows a chocolate 3D printer developed by Procusini, a German-based company, targeting the infant food industry. Ongoing 3D food fabrication researches orient towards the printing of meat and probiotics incorporated foods.

Figure 4. (a) A commercial 3D food printer (b) 3D printed chocolate

 

 

Table 3. 3D food printers developed for commercial 3D printing

3D printer model

Company

Target products

Chefjet™ Cocojet

3D Systems

Chocolate

Foodini™

Natural Machines

Pizza, cookies

CandyFab 3D printer

Evil Mad Science

Sugar-based confectionary

PancakeBot™

Digital Food Lab

Pancakes

3D pasta printer

Barilla

Pasta

Nufood 3D Food printer

Dovetailed

Fruit-based confectionary

Concluding remarks

For the past years, two-dimensional food printing in the form of text or graphics on cakes or cookies are widely available. The approaches of 3D, 4D printing enable the food manufacturing with a wider perspective of complex geometry and shapes in a relatively shorter period. The main advantage here is the lack of laborious and time-consuming unit operations, which is unlike the conventional food processing methods. However, the limitations of 3D, 4D food printing are its relative higher working time, tedious optimization of working parameters, and the costly equipment.

Presently, research on food printing aims to combine 3D, 4D printing with other established technologies like electrospinning and microencapsulation for improved nutritional profile. Despite, 3D, 4D printing is suitable to fortify food with micronutrients to combat malnutrition and nutrient deficiency. Moreover, whence the technology is accessible by small-scale processing units, its consistent use for novel consumer foods is at vicinity.

 

1PhD Scholar, University of Queensland IIT Delhi Academy of Research (UQIDAR), Indian Institute of Technology, Delhi

2Assistant Professor (Agriculture Engineering), SIET (Anna University), Coimbatore, TN

vithuprabha@gmail.com