Abstract
This study investigates the dynamic ranges of key properties in three-dimensional (3D) food binder jetting, a process in which liquid binder is selectively applied to bind edible powder particles together. Currently, research in this area remains limited, often relying on trial-and-error and a narrow range of materials. Therefore, the research presents a methodological approach for investigating ingredient-binder combinations to optimise the 3D-printed food properties. Three powdered food ingredients (sucrose, whey protein isolate, and carboxymethyl cellulose), each representing different proximate chemical classes of foods, were combined with four edible binder solutions containing water, ethanol, xanthan gum and Tween 20. A systematic investigation was conducted to examine the relationships between the physicochemical characteristics of these materials and the resulting printed product properties. The findings highlight that powder particle size and density significantly affected the product properties, whereas the choice of binder has a substantial impact only when paired with a specific powder.
Highlights
- Powder characteristics play a dominant role in determining the properties of the 3D-printed products.
- The optimal binder combinations for producing food with high resistance are 20% ethanol solution for sucrose and whey protein isolate powders, and 0.4% xanthan gum solution for carboxymethyl cellulose.
- Water is the most suitable binder for creating high-dimensional products.
- Significant correlations between investigated material and printed product properties provide a valuable framework for tailoring 3D-printed foods.
- A systematic approach to optimising printing materials can address the limitations of traditional trial-and-error methods.
Introduction
As consumer understanding of the food they consume has increased, so has their desire for new, customised products that are tailored to each individual’s preferences and health requirements (Fig. 1A). Consequently, 3D printing, which can reduce the cost and equipment required for the creation of complex, customised foods, has emerged as a new solution to meet consumers’ demands and support the development of traditional food processing methods (Kouzani et al., 2016; Sun et al., 2015). 3D food printing techniques can be divided into four primary categories: extrusion methods, hot air sintering, liquid binding (including binder jetting), and selective laser sintering, each with its own advantages and drawbacks (Mantihal et al., 2020). Food binder jetting is a process of manufacturing 3D objects by joining sequential layers of edible powder components by selectively depositing liquid “binders” (also known as binding agents or inks) in the powder bed based on a computer-designed pattern (Fig. 2A) (Jiang et al., 2022). In contrast to other 3D printing methods like fused deposition modelling, the powder bonding mechanisms in this technology rely mainly on the binder acting as an adhesive to bind the powder particles together and secure powder layers without the need for additional processing factors like heat treatment (Kreft et al., 2022). Thus, the shaping process can occur at room temperature. This helps the unbound powder retain its characteristics by preventing oxidation reactions or phase shift issues, making it fully recyclable (Jiang et al., 2021; Mostafaei et al., 2021). Moreover, the unbound powder that surrounds the product serves as a support material in this process, eliminating the need for additional support structures (Mostafaei et al., 2021). Lastly, binder jetting can print colour on specific food parts using a coloured binder, enabling visually appealing and customisable designs (Fig. 1B).
When food-grade materials are used for binder jetting, the powder particle surfaces usually dissolve and fuse, a process known as cross-linking (Godoi et al., 2016). Food powder particles are often the primary adhesion since they tend to stick together through a physicochemical process known as “caking” when exposed to moisture. In these cases, moisture from the binder acts as a solvent, dissolving the outer layers of each particle and causing them to bond together when dried (Fig. 2B) (Günther et al., 2016). However, in some cases, the binder, or “ink,” functions as the binding agent. This is usually due to the presence of hydrocolloids like xanthan gum or pectin in the ink that can form particulate agglomerates when the binder dries or hardens around the powder particles (Saha and Bhattacharya, 2010). Therefore, understanding the initial material characteristics as well as the complex binding mechanism between them is essential for creating successful prints.
Although binder jetting has been extensively studied for non-food materials, only a few studies have investigated the possibilities of using food-grade materials for this technology, as summarised in Table 1. Most studies in food binder jetting focus on optimising only one type of material (such as sugar or cellulose) in combination with a specific binder and printer, resulting in samples with highly variable properties (Chadwick et al., 2024; Holland et al., 2017; Southerland et al., 2011). This limits the applicability of findings to other materials due to variations in machine specifications and material choices (like different binder formulations used in each study). Moreover, while there are some suggestions on open forums such as Open3DP (University of Washington, 2015) or by food manufacturing companies such as Sugar Lab about new formulas for food binder jetting (Enfield et al., 2023), there is a lack of scientific studies into the properties of printed foods using these formulas. This gap can be attributed to restrictions on sharing composition of powder and binder materials due to their intellectual property policies (Doherty, 2012) and material customisation limitations inherent to commercial binder jetting printers. For instance, proprietary systems like ZCorp printers often require modifications to accommodate alternative binders (Sarat et al., 2018). Lastly, research on the effects of influencing parameters such as material characteristics or printer settings on printed products is primarily focused on the non-food sector (Mostafaei et al., 2021). As a result, systematic research is needed to explore these effects under controlled printing conditions on 3D printers that are more affordable and accessible to industry and consumers. This approach can bridge the existing knowledge gaps in 3D-printed food production, particularly by reinforcing the foundation for multi-material products and advancing the development of food binder jetting technologies.
This study is based on the hypothesis that the characteristics of food powders and binders have a distinct impact on their behaviour in the printed mixture, as well as the properties of 3D-printed food products. Therefore, studying on the combination of materials with a broad dynamic range of characteristics can establish a framework for developing a predictive tool to tailor food products with targeted qualities. This can include desirable attributes such as a smooth printed surface that will improve the visual appeal to customers or good mechanical properties, which are suited for food applications. The research investigates a range of chemically diverse powders, including disaccharide sugar, protein, and polysaccharide, alongside binding suspensions composed of water, ethanol solution, and two hydrocolloid solutions, with and without a wetting agent. The aim is to (i) systematically study the relationships between the physicochemical characteristics of input materials and the resulting properties of printed products regarding surface morphology, area, and cutting resistance and (ii) to investigate how these correlations can be further leveraged to tailor the surface morphology, mechanical properties and thus the functional attributes of 3D-printed food products. Using fixed printing conditions on a binder jetting printer, the characteristics of the input materials and the functional/texture properties of 3D-printed products were mapped, and correlations between them were determined.
Read more here
Materials
Food-grade sucrose and xanthan gum powders used in this study were sourced from The Melbourne Food Depot, Australia. Food-grade carboxymethyl cellulose (CMC) powder was obtained from Roberts Edible Craft, Australia. Whey protein isolate (WPI) powder with 90% purity was provided by Bulk Nutrients, Australia. Analytical grade polysorbate 20 (Tween 20) and absolute ethanol were used as received from Sigma Aldrich, Australia.
Dang Chung Nguyen, Rico F. Tabor, Yunlong Tang, Louise Bennett, Shahnaz Mansouri, EFFECTS OF SELECTED FOOD-COMPATIBLE PRINTING MATERIALS ON PRODUCT PROPERTIES TOWARDS 3D BINDER JETTING, Journal of Food Engineering, 2025, 112779, ISSN 0260-8774, https://doi.org/10.1016/j.jfoodeng.2025.112779.
