Optimization of chocolate 3D printing by correlating thermal and flow properties with 3D structure modeling

Abstract 3D printing is a new promising technology capable of creating intricate food shapes. To stabilize the mechanical properties of the complex printed food it may require support structures. The 3D shape of chocolate was designed with different support structures (cross support, parallel support and no support) and its effect on the snapping properties was investigated. This study also determined the relationship between the physical properties of chocolate used for printing and the quality of the printed 3D constructs. The dimensions (wall thickness, height, and diameter), weight as well as physical properties (melting properties, flow behaviour, snap ability) of the 3D printed chocolate were evaluated. The nozzle temperature before deposition was maintained at 32 °C in order to extrude the melted state of the sample as the flow behaviour curves indicated that the melting of chocolate started between 28 °C to 30 °C. Incorporation of Magnesium Stearate (MgST) in the chocolate formulation aid in material lubrication and increase flow efficiency during deposition. Results showed that there was a minor difference between the predetermined diameter and the actual output diameter for each sample suggesting similarity between the printed 3D structure and the pre-designed 3D model. Wall thickness of printed item varied along the height due to uneven deposition of chocolate as the layer height increased. The breaking strength of the sample was strongly related to the additional support structure, with 3D chocolate with cross support structure requiring the highest force (N) to break the sample. Industrial relevance The development and production of food with 3-Dimensional printing (3DP) technology has potential to create and produce food in a more advanced format that will be a new paradigm shift in the food industry. Through 3D printing, personalised food can be created in terms of shape and nutritional composition. To firmly establish this promising technology as a powerful tool for engineering food it is required a thorough understanding of the supply ingredients and strategies to enhance printability. This study demonstrates the use of flow enhancer and inclusion of support structure in the designed shape were key factors influencing printability capacity of chocolate (edible ink chosen as a model).

[1]  Amit Mehrotra,et al.  Effect of moisture and magnesium stearate concentration on flow properties of cohesive granular materials. , 2007, International journal of pharmaceutics.

[2]  E. Lutton,et al.  Polymorphism of cocoa butter , 1966, Journal of the American Oil Chemists' Society.

[3]  E. Afoakwa Chocolate Science and Technology , 2010 .

[4]  Antonio Derossi,et al.  Variables affecting the printability of foods: Preliminary tests on cereal-based products , 2016 .

[5]  Mark Fowler,et al.  Flavor Formation and Character in Cocoa and Chocolate: A Critical Review , 2008, Critical reviews in food science and nutrition.

[6]  Hod Lipson,et al.  Fabricated: The New World of 3D Printing , 2013 .

[7]  E. Afoakwa,et al.  Modelling tempering behaviour of dark chocolates from varying particle size distribution and fat content using response surface methodology , 2008 .

[8]  Jinjiang Li,et al.  Lubricants in Pharmaceutical Solid Dosage Forms , 2014 .

[9]  Chee Kai Chua,et al.  Roles of support materials in 3D bioprinting - Present and future , 2017, International journal of bioprinting.

[10]  A. Stapley,et al.  The effect of shear rate, temperature, sugar and emulsifier on the tempering of cocoa butter , 2006 .

[11]  Bhesh Bhandari,et al.  3d printing technologies applied for food design: Status and prospects , 2016 .

[12]  Mark Fowler,et al.  Factors influencing rheological and textural qualities in chocolate - a review , 2007 .

[13]  Liang Hao,et al.  Material characterisation and process development for chocolate additive layer manufacturing , 2010 .

[14]  K. McCarthy,et al.  RHEOLOGY OF DIFFERENT FORMULATIONS OF MILK CHOCOLATE AND THE EFFECT ON COATING THICKNESS , 2006 .

[15]  André R. Studart,et al.  Cellulose Nanocrystal Inks for 3D Printing of Textured Cellular Architectures , 2017 .

[16]  Jun-Ichi Kikuta,et al.  Effect of mixing time on the lubricating properties of magnesium stearate and the final characteristics of the compressed tablets , 1994 .

[17]  Wai Yee Yeong,et al.  A preliminary model of time-pressure dispensing system for bioprinting based on printing and material parameters , 2015 .

[18]  P. Fryer,et al.  The effects of shear and temperature history on the crystallization of chocolate , 1999 .

[19]  H. Kodama Automatic method for fabricating a three‐dimensional plastic model with photo‐hardening polymer , 1981 .

[20]  Eman M. Mostafa,et al.  Quality characteristics of chocolate – Containing some fat replacer , 2011 .

[21]  Anthony Atala,et al.  3D bioprinting of tissues and organs , 2014, Nature Biotechnology.