The motivation behind the work lies in one of the most pressing challenges of the coming decades. The world’s population, which surpassed 7.6 billion in 2018, is projected to reach 9.2 billion by 2050, and food demand is expected to rise by anywhere from 59 to 102 percent. Global meat consumption is anticipated to climb in parallel, reaching an estimated 4.55 million tons by 2050, with developing countries accounting for 56 percent of feed grain consumption. Against this backdrop, cultured meat, produced by cultivating livestock cells rather than slaughtering animals, has attracted intense interest as a way to conserve finite resources, address animal welfare concerns, and reduce the environmental footprint of protein production. Yet conventional cultured meat approaches, which rely on cells alone, have largely been limited to simple forms such as patties.

This is where 3D bioprinting enters the picture. By depositing cell-laden materials layer by layer, bioprinting can produce constructs in a wide variety of shapes that more closely mimic traditional meat products. It also allows researchers to optimize the cell growth environment, shortening production time, minimizing raw material use, and improving cost-effectiveness, while opening the door to customized meat tailored to individual dietary preferences or health needs. The critical enabling ingredient in this process is the bio-ink itself, typically built from materials such as alginate and gelatin, whose properties ultimately determine the quality of the final product. Gelatin, a degradation product of collagen, is prized for its excellent biocompatibility and its ability to support cell attachment, proliferation, growth, and differentiation, all of which are essential for natural and efficient tissue formation.

What has been missing, the authors argue, is a food-focused perspective. Most prior studies of gelatin-based bio-inks have been rooted in tissue engineering and biomedical applications, prioritizing biocompatibility and mechanical performance without adequately considering edibility, food-grade applicability, and source-dependent functionality within a food system. For cultured meat, bio-ink materials must simultaneously provide structural stability and printability while remaining suitable for consumption and scalable for food production. Systematic comparisons of edible animal-derived gelatin sources under standardized formulation conditions have been scarce, so the Korean team set out to fabricate bio-inks from bovine, porcine, and fish gelatin powders under unified conditions and to evaluate how source and concentration independently and interactively influence rheological behavior, printability, and structural properties.

The experimental design was straightforward but rigorous. Beef gelatin from Holstein cattle, pork gelatin from Landrace-Yorkshire-Duroc pigs, and fish gelatin from salmon, all with molecular weights ranging from roughly 10 to 100 kilodaltons depending on source, were dissolved in distilled water at concentrations of 4, 12, 20, 32, and 40 percent by weight at 45 degrees Celsius. Because gelatin-only formulations showed insufficient thermal stability at the 37 degrees Celsius incubation temperature used in cell culture, each gelatin solution was mixed 1:1 with a 6 percent sodium alginate solution, a supporting polymer that improves structural stability during printing and post-printing incubation. The blends were loaded into printing cartridges and stored at 4 degrees Celsius before testing. Printability trials used a Cellink BIO-X bioprinter with 27-gauge conical nozzles, a print bed held at 10 degrees Celsius, a print speed of 5 millimeters per second, and a pressure of 150 kilopascals, followed by ionic cross-linking in a 100 millimolar calcium chloride bath.

The results revealed systematic patterns across nearly every measured property. As gelatin concentration increased, pH decreased in all three sources, a trend the researchers attribute to the rising content of acidic amino acids such as aspartic and glutamic acid, which elevate hydrogen ion concentration as collagen breaks down into gelatin. Notably, fish gelatin samples consistently showed the highest pH values, a difference thought to reflect the vitamins, minerals, and amino acid profiles specific to each livestock species. Because higher pH levels are associated with increased metabolic activity in cells, the authors suggest that bio-inks with elevated pH may be particularly suitable as scaffold materials for cultured meat production. Color measurements told a complementary story: lightness declined with increasing gelatin concentration while redness and yellowness rose, and beef gelatin samples were significantly more yellow than the others, likely because bovine gelatin contains more lysine and other amino acids susceptible to the Maillard reaction, the non-enzymatic browning that occurs when the powder is dried in the presence of atmospheric oxygen.

Viscosity, arguably the most important rheological property for extrusion printing, showed the sharpest source-dependent differences. Initial viscosity increased with gelatin concentration in all formulations, but pork gelatin exhibited the highest values across every concentration tested. The explanation lies in molecular architecture: pork gelatin possesses greater structural integrity of its beta and gamma chains, creating physical entanglements that impede polymer flow, whereas fish gelatin has a looser structure with weaker intermolecular bonds and lower levels of proline and hydroxyproline, the amino acids that govern gelation and melting point, making it heat-sensitive and unable to build high viscosity even at elevated concentrations. Intriguingly, the most concentrated pork gelatin formulations, at 32 and 40 percent, showed viscosity that declined over time, apparently because excessive intermolecular interactions at very high concentrations prevent the formation of a stable gel network and increase internal stress. This observation led the team to recommend keeping porcine gelatin below 32 percent when manufacturing bio-ink.

Printability tests drove the study’s central conclusion home. At 4 percent, all three gelatin types extruded as a liquid with no visible lattice formation whatsoever. Beef and fish gelatin at 12 and 20 percent could be extruded but collapsed rapidly, retaining lattice structures only up to 0.3 centimeters in height. Pork gelatin, by contrast, formed partial lattices at 12 and 20 percent and was the only formulation to maintain scaffold integrity up to 0.5 centimeters. At 32 and 40 percent, pork gelatin became so solidified that it could not be extruded at all, a consequence of hydrogen bonding and van der Waals forces increasing the material’s elastic restoring force until it behaved more like a solid than a printable viscoelastic fluid. The richer proline and hydroxyproline content of porcine gelatin appears to foster stronger hydrogen bonding and a more stable three-dimensional network, providing the internal binding strength needed to resist gravitational collapse after deposition.

Structural analysis and statistical correlation rounded out the picture. Under the microscope, pork gelatin scaffolds displayed rougher surfaces than the other sources, a feature that may actually benefit cultured meat production by increasing surface irregularities and contact area for cell attachment. The 20 percent pork gelatin sample showed significantly higher grid size and gel strength than all other formulations, a combination the researchers highlight as a favorable balance: larger grid sizes facilitate nutrient diffusion and material exchange within the printed structure, while greater gel strength preserves scaffold integrity during handling and culture. Pearson correlation analysis quantified these relationships, revealing a strong positive correlation between gel strength and viscosity with a coefficient of 0.88, and between grid size and gel strength with a coefficient of 0.89. Even color proved tightly linked, with redness and yellowness showing a near-perfect correlation of 0.99, suggesting that bio-ink color tone can be controlled predictably, an attribute the authors note matters for the appearance quality control of commercial cultured meat.

Taken together, the findings offer a practical recipe for the emerging cultured meat industry: choose pork gelatin, keep the concentration near 20 percent, and pair it with alginate for thermal stability. The work also underscores a broader lesson in biomaterials science, that seemingly minor differences in molecular composition, down to the amino acid content of a protein extracted from a particular animal’s skin, can cascade into dramatic differences in how a material flows, gels, and holds its shape under a printing nozzle. As the demand for alternative proteins accelerates, studies like this one, which treat food-grade applicability as seriously as mechanical performance, will help determine whether 3D-printed cultured meat can move from laboratory demonstration to dinner plate.

Subject of Research: Physicochemical and printability properties of animal-derived gelatin bio-inks for 3D-printed cultured meat scaffolds

Article Title: Physicochemical properties of 3D bio-ink prepared with beef, pork, and fish gelatin

Article References: Kang, K.-M., Lee, S.-H., & Kim, H.-Y. (2026). Physicochemical properties of 3D bio-ink prepared with beef, pork, and fish gelatin. Food Science of Animal Resources, 46(1), Article 66. https://doi.org/10.1007/s44463-026-00071-y

Image Credits: AI Generated

DOI: 10.1007/s44463-026-00071-y

Keywords: gelatin, bio-ink, 3D bioprinting, cultured meat, pork gelatin, printability, viscosity, gel strength, scaffolds, sodium alginate, food science, collagen