image: Gels were created with different ratios of gum tragacanth to gelatin (top) to compare their properties to those of gum tragacanth (bottom left) on its own and of gelatin (bottom right) on its own.
Credit: Ezgi Pulatsu
WASHINGTON, April 1, 2025 – With increased awareness about food sources and their environmental impacts, replacing animal-derived products in food and drugs is a significant research area. One common — but often overlooked — animal protein is gelatin, found everywhere from candy to plastic-free packaging.
In Physics of Fluids, by AIP Publishing, researchers from the University of Ottawa present gum tragacanth as a plant-based alternative to gelatin for creating edible films.
“Gelatin has unique properties and its use is versatile,” said author Ezgi Pulatsu. “To fully replace gelatin, we must replicate its microstructure and understand its function in different applications.”
Gelatin’s gel-like structure and its transparency are just two of its qualities that a plant-based alternative must replicate. Gum tragacanth, a byproduct of the sap in certain legume plants, is promising in both of these characteristics.
To test just how promising it is, Pulatsu’s team developed films containing different concentrations of gelatin and gum tragacanth — some constructed with alternating layers, others a mixture of the two — and monitored their survivability in water and saline solutions. They found the optimal combination of gum tragacanth and gelatin for maintaining the gelatin’s gel-like behavior was a 3-to-1 ratio of the two, respectively. However, gum tragacanth’s inclusion leads to a more porous film, making it prone to penetration by water or saline solutions.
Though gum tragacanth cannot replace gelatin completely just yet, the researchers continue their work on developing a fully plant-based alternative. Pulatsu said one path forward is to improve gum tragacanth’s suitability on its own through various chemical and structural modifications that can increase its mechanical and barrier properties, but noted that even a partial replacement is a step forward.
“Partial replacement of gelatin will reduce animal-based product use,” Pulatsu said. “Our efforts in the full replacement of gelatin are ongoing.”
Specific applications will each have their own challenges to consider. For example, replacing gelatin in candy requires special attention to gum tragacanth’s impacts on sweetness, texture, and transparency, while brittleness and flexibility are key factors for food packaging.
“We are very excited to see the outcomes and share them with the community,” Pulatsu said.
###
The article “Edible films based on gum tragacanth and gelatin” is authored by Ezgi Pulatsu, Jiaqian Xie, Qinling Wang, and Chibuike C. Udenigwe. It will appear in Physics of Fluids on April 1, 2025 (DOI: 10.1063/5.0253890). After that date, it can be accessed at https://doi.org/10.1063/5.0253890.
ABOUT THE JOURNAL
Physics of Fluids is devoted to the publication of original theoretical, computational, and experimental contributions to the dynamics of gases, liquids, and complex fluids. See https://pubs.aip.org/aip/pof.
###
Journal
Physics of Fluids
Article Title
Edible films based on gum tragacanth and gelatin
Article Publication Date
1-Apr-2025