Cellulose as an Edible Ingredient for 3D Printing

Sonia Holland, PhD StudentEPSRC CIM in Food and EPSRC CIM in Additive Manufacturing, University of Nottingham

3D Food Printing Conference, Venlo, NL 12th April 2016

Presentation Overview

• Why use cellulose?

• Pre-processing to enable printing

• Application to Additive Manufacturing - Binder Jetting

Designer Particles

Complex Structures

Image from : Frisullo, P., Conte, A. & Del Nobile, M.A., 2010. A novel approach to study biscuits and breadsticks using X-Ray computed tomography. Journal of Food Science, 75(6).

Image from European Powder Metallurgy Association

What is Cellulose?

Image from : http://bio1151.nicerweb.com/Locked/media/ch05/cellulose.html

Glucose is the basic building block

Hierarchical chain structure

Hydrogen bonds→tight packing

→crystalline, rigid structure for strength

≈1011-1012 Tons synthesized annually by

plants!

Abundant Natural

Cellulose in the Human Diet

• Impossible to estimate how much we consume daily

• No human enzyme to digest cellulose

• Not fermented by gut bacteria

→0 kcalg-1

→Dietary fibre without excess gas production

• Crystalline structure difficult to dissolve

• Often derivatised to partially/fully soluble materials

→ Native cellulose typically “bulking agent”

Ball Milling to Alter Properties

Image from : Varol et al. 2013. Prediction of the influence of processing parameters on synthesis of Al2024-B4C composite powders in a planetary mill using an artificial neural network. Science and Engineering of Composite Materials. 21(21(3)):411-420 [available online] :http://www.degruyter.com/view/j/secm.2014.21.issue-3/secm-2013-0148/graphic/secm-2013-0148_fig1.jpg

10μm10μm

Native Cellulose Fibre Cellulose Ball Milled for 30min at 800rpm

Physical Size Reduction

Decreased Molecular Chain Length

Loss of Crystallinity

Recrystallisation to Structure3

4.2

5

5.5

6.7

5 8

9.2

5

10

.5

11

.75

13

14

.25

15

.5

16

.75

18

19

.25

20

.5

21

.75

23

24

.25

25

.5

26

.75

28

29

.25

30

.5

31

.75

33

34

.25

35

.5

36

.75

38

Intensity

2θ

X-Ray Diffraction Data Showing Sample Crystallinity

Native Cellulose(27%)

RecrystalisedSample (20%)

Cellulose BallMilled 30min(<5%)

200 arbitrary

units

Thermal analysis of samples undertaken

Control of moisture and temperature allows recrystallisation control

Addition of structurally similar polysaccharides can introduce further interactions and control

e.g. Locust Bean Gum (Galactomannan)GlucomannanXanthan Gumβ-Glucan (from Oat)

Schematic of Binder Jetting

• Powder building material

• Liquid binding material

• Layer by layer approach – 3D model split

into 2D cross sections of a defined

thickness

• Binder deposition nozzle diameter 21μm

(10pL) or down to 10 μm (1pL)

• Potential for 24-bit colour printing

Gaudi-inspired Sugar Structure by 3DSystems

Binder Jetting image from : https://www.additively.com/en/learn-about/binder-jettingSugar Structure : http://www.3dsystems.com/culinary

AM Process - Binder Jetting

My Materials

Binder Jetting image from : https://www.additively.com/en/learn-about/binder-jetting

Powder : Ball Milled Cellulose with/without

interacting polysaccharide

Ink : Providing necessary moisture to induce recrystallisation

with interacting polysaccharide

• Powder bed and ink temperature controlled

• Nozzle selected to provide desired moisture

• Not only simple particle adhesion

→ Recrystallisation induced will lead to a more robust structure

Future Work

• Ink development and analysis

• Combine powder and ink in process to develop a working model

• Modify polysaccharides in powder and ink to change structural properties and develop for food use

Drop watcher on Dimatix ink jet printer

Thank you for your attention,Any questions?

Sonia Holland - PhD StudentDivision of Food Sciences, University of Nottingham Sutton Bonington Campus,

Loughborough, LE12 5RD