This chapter underscores the necessity of 4D printing in the contemporary and future food industry to captivate consumers and drive the development of innovative products. It emphasizes the significance of 4D printing technology, detailing its potential, mechanisms, and the types of printers utilized. Additionally, the chapter presents various case studies to exemplify the practical applications and advantages of 4D printing in the realm of food production.

1. WELCOME 1

2. DIVISION OF AGRICULTURAL ENGINERRING
INDIAN AGRICULTURAL RESEARCH INSTITUTE, NEW DELHI
PFE 692 Doctoral Seminar
4D PRINTING OF FOOD PRODUCTS
Course Leader:
Dr. Rouf Ahmad Parray
Scientist
Presented By:
Rajvardhan Patil
11675
Ph D 2nd year
Chairperson:
Dr. Indra Mani
JDR (ICAR-IARI) & Head
Division of Agril. Engg

3. • Intelligent printing manufacturing is developed as an advanced technology compared to
conventional manufacturing technology, which is known as 3D and 4D printing technologies.
• 3D printing has boosted the application fields according to its several characteristics, such as
short-time process, low-cost, customization, and material reduction.
• However, the conventional 3D printing technology is used to fabricate static structures from
commercial single or more filaments, which cannot meet the needs of dynamic structures.
Introduction
Wang et al., 2017

4. • 4D printing technology is an extension of 3D printing, where the addition of “space-time
axis” on the basis of 3D coordinate axis occurs.
• The concept of 4D printing was proposed by Professor Tibbits of Massachusetts
Institute of Technology (MIT) in 2013.
• The existence of smart materials like shape memory alloy promotes the application of 4D
printing technology in aerospace, automobile, soft robot, biomedicine, food etc.
• The food materials used for printing inks are generally non-smart materials in contrast to
shape memory alloy.
• Properties of printed products (shape, color, taste, texture, nutrition) produce predictable
changes (water, heat, light, pH).
• The basic components of 4D food printing are 3D printers, printing software, inks,
structural design and stimulants (water, heat, magnetic field, light, pH etc.).
4D Printing Technology
Transformation
from 1D to 3D
Skylar Tibbits

5. 4D printing is “ the process of building a physical object
using appropriate additive manufacturing technology,
laying down successive layers of stimuli-responsive
composite or multi-material with varying properties. After
being built, the object reacts to stimuli from the natural
environment or through human intervention, resulting in a
physical or chemical change of state through time ” (Pei,
2014).
Momeni et al., 2017

6. Difference between 4D and 3D printing
 4D printing can achieve suspended structures that 3D printing cannot do, such as blooming flowers. The
transition of flowers from closure to bloom makes eating more interesting, which attract more attention from
consumers like fussy children.
 4D printed food provides new ideas for the design of interactive food and enhances the interaction between
diners and food materials.
 The flavor, nutrition or color of the 4D printed food products can be released when the user eats it rather than
during storage.
 In contrast, these sensory or nutritional properties of 3D printed products decrease during storage.
 3D printing food is not suitable for drying because drying causes unwanted and irregular deformation which
undermines the usefulness of 3D printing. 4D printing is beneficial for controlling the structure changes during
drying, which is used to make some healthy snacks.
 For example, the better crispy mouthfeel of potato chips is partly due to the curvature of the chips. The
combination of 4D printing and drying produces the products with a crispy texture.
 4D printing of food products is very compatible with the concept of “flat packaging”. This concept fits well
with deformed food prepared by 4D printing, which reduces transportation costs and storage space

7. • Fused Deposition Modelling (FDM)
[Cartesian, Delta, Polar and Scara]
• Stereolithography
• Direct Ink Writing
• Inkjet
• Digital Light Processing
• Selective Laser Sintering
Printers for 4D printing
Extrusion based
Printing

8. Printer Stimulation Device Main Features Reference
Printer is equipped with infrared
heating device
• Non-contact heating
• Selective heating
Hertafeld et al., 2019
Printer is equipped with Laser
heating source
• Uniform heating and precise
local heat capacity.
• Repeatable and precise control
of energy transfer.
Blutinger et al., 2019
Bottom plate is provided with the
microwave heating device.
• Dielectric properties
- material formulation
- microwave power
• Different heat absorption rate
Liu et al., 2019
Multi-nozzle extrusion device • Material composition of each
layer different
• Different material properties
Huang et al., 2018
Types of cartesian FDM printer based on 4D printing technology

9. Printing software's required
 Forward design is to determine final changes according to
material structures. 4D food printing mainly focuses on
forward design due to the lack of intelligent food materials.
 Reverse design is primarily a bionic design, mainly based on
the nature of plants and animals as the prototype, such as
flowers are endowed with the ability to respond to external
stimulation (heat, water, light, etc.) by regulating the
mechanical asymmetry of tissue composition and cell walls.
 4D simulation software can simulate the printing process, optimize the physical quantity (viscosity, pressure, uniformity,
etc.) in the printing process, and reduce the risk of printing failure.
 Modelling software is the equivalent of a printed blueprint. These modelling software-123D, AutoCAD, CATIA,
Solidworks, Rhinoceros
 Specifically, the slicing software splits the 3D model into 2D parts and generates the required information. The slicer
generates the G-code according to the calculated material layering path, the required speed and the amount of extrusions
by using the accumulated 3D object data

10. 10
Printing materials suitable for 4D printing
4D food printing
• Chocolate
• Dough
• Cheese
• Hydrocolloid
• Starch
• Algae
• Meat
• Fruits
• Vegetables
• Starch gels
• Soy protein isolate
• Hydrogels
- gelatin, pectin
Healthy ingredients
• Vitamins
• Fibers
• Phytochemicals
• Fat, Protein

11. Changes in color due to 4D printing
 The color change of the recombined food is mainly induced by the existence of plant pigments in
different chemical forms under different pH conditions.
 This allows 3D printed food to change its color to an attractive color over time after response to
external or internal stimulation (4 dimension), which helps to increase the interaction with
consumers
Visual images of stimulus concentration and time-dependent color transformation of the 3D-printed constructs
Shanthamma et al., 2021

12. Ghazal et al., 2019
Changes in color due to 4D printing
Spontaneous color changes of 3D printed anthocyanin-PS
gel
Multi-material 3D printing of mashed potatoes with
different pH/purple sweet potato puree.
He et al., 2020

13. • Deformation behaviors in 4D food printing include bending, distortion, linear or nonlinear
expansion/contraction and surface curl.
• At present, the deformation of food mainly depends on water absorption and dehydration
• The degree and direction of shape change depends on the difference in properties and spatial
arrangement of the two or more materials
Changes in shape due to 4D printing
Wang et al., 2017
Gelatin films

14. Changes in shape due to 4D printing
Shape transformation and quantification of hydromorphic tapioca xerogel with time. a) without
constraint b) with constraint
a
b
Jaspin et al., 2021

15. • Inspired by 4D biotechnological printing, inks and cells are replaced with food-grade materials. Edible cells
grow in edible substrate when stimulated by appropriate conditions (temperature, humidity, light, etc).
• Printed objects containing plant or animal cells have the potential to form tissue-like structures that would
reproduce the nutrients observed in real food.
• This is positive for the corresponding craze for artificial meat and for older people who have difficulty in
swallowing it.
Changes in nutritional quality due to 4D printing
Rutzerveld et al., 2014
Edible growth food with short food production chain

16. Changes in nutritional quality due to 4D printing
Printing behavior of purple sweet potato pastes of different compositions. A-D represent the different formulations;
I-Ⅶ represent numbers of models used to investigate nutritional conversion.
• UV-C irradiation was performed to convert ergosterol into vitamin D2.
Chen et al., 2021
Irradiation
time (h)
Initial ergosterol
content (mg)
Final content
of Vit D2 (g)
0 4.465 0
2 4.438 5.343
4 4.455 7.268
6 4.448 4.010
Irradiation area
(mm2)
Initial content of
ergosterol (mg)
Final content
of Vit D2 (g)
576 4.460 3.631
864 4.450 4.035
1152 4.460 4.585
Effect of UV-C irradiation exposed area on conversion
of ergosterol to Vit D2
Effect of UV-C irradiation on conversion of
ergosterol to Vit D2

17. Changes in flavor due to 4D printing
• Desired flavor change occurs under the stimulation of pH or microwave.
• Capsules containing special flavor substances are added in inks (slow-release effect).
Aroma changes soy protein isolate,
k-carrageenan, and vanilla flavor
after microwave heating at various
power levels
Characteristics 0W 50W 80W 110W
Sourness -34.53 -31.43 -30.53 -28.51
Bitterness 11.39 11.55 12.44 13.7
Astringency -5.28 -6.67 -6.84 -7.84
Aftertaste B -0.24 -0.21 -.016 -0.34
Aftertaste A 0.05 0.05 0.09 0.11
Umami 5.04 5.04 6.49 8.25
Richness 0.67 0.67 0.88 1.04
Saltiness 2.03 1.93 2.24 3.49 Phuhongsung et al., 2020
Taste characteristics of 4D
printed products

18. ADVANTAGES
Personalized nutrition
Nutrient enrichment
Reducing food waste
Customized food design
Process digitalization
Complex food structures
Innovation
Cost reduction
LIMITATIONS
 Expensive printers and printing materials
 Smart material loading is difficult in the
printer head
 Investment opportunities and legal issues of
printed food
Advantages and limitations of 4D printing

19. • 4D food printing technology is an extension of the developed 3D printing technology, which
allows the flexibility of food customization by adding desired characteristics.
• At present, printed food materials are mainly limited to soy protein isolate, starch gels and
hydrogel systems, with the external stimulation factors of pH, water absorption, microwave and
temperature.
• Properties alterations (color, shape, nutrition and flavor) of the printed product depend on the
differences in material properties, internal structural design and spatial arrangement of food
materials.
• With the development and popularization of printing technology, it can be added to the production
line to achieve automatic production.
CONCLUSION

20.  Strengthening the link between internal structure and stimulation: Synergy between
the internal structure and stimulation of printed food.
 Creating new printing conditions: Emergence of new materials and new technologies
 Innovating properties changes: Intelligent food materials, new stimulation factors
 Building evaluation and verification methods for the printed samples: Dimensional
accuracy and stimulation, ingredient mix rheology, structure accuracy, shape stability,
printing speed
 Compatibility with traditional food processing technologies
(e.g. baking and drying)
FUTURE CHALLENGES

21. THANK YOU