Biomaterials are a broad family that includes cellulose derivatives (cellulose acetate, carboxymethyl cellulose), polylactic acid, chitosan and starch. These materials are renewable, biodegradable and safe, but unfortunately they have some critical issues, including low mechanical strength, poor moisture resistance and high costs. To solve these problems, one of the following methods is usually used:
- blending with conventional plastics, which do not have these drawbacks but result in blends whose properties are difficult to tailor;
- the incorporation of metal oxides, which, however, may pose risks to the safety of the materials;
- the modification of biomaterials through processes which, however, are generally complex.
Given the limitations of currently used methods, there is a great need for new technologies to advance the use of biomaterials in the food sector. Nature may be instrumental in solving these challenges and leading to the production of high-performance biomaterials. The concept of “learning from nature” is already used in materials science but is still relatively underexploited in food packaging. To fill this gap, S. Hu et al. (2025) from Nanjing University (China) have compiled the results obtained so far in this field, highlighting how inspiration from nature can lead to the development of new biomaterials with beneficial properties such as high mechanical strength, superhydrophobicity, self-healing ability, and the possibility of monitoring food freshness in real time. Among these properties, superhydrophobicity is receiving increasing attention in the field of food packaging. This is the property of highly hydrophobic materials, which have a contact angle with water greater than 140°-150°, allowing water droplets to form a spherical shape and slide off without adhesion. Reducing the wettability of the material’s surface can not only inhibit microbial growth, maintain the dryness of food products, and significantly extend their shelf life, but can also provide the technological basis for the development of packaging materials based on unmodified cellulose. The main source of inspiration for the development of superhydrophobic materials is swan feathers and lotus leaves, among other materials.
Swan feathers are highly water-resistant thanks to their multilayered structure, the presence of micrometer-sized protrusions, nanometer-sized scales, and a layer of surface oils, which together form a completely waterproof barrier. Similarly, lotus leaves have densely packed microscopic papillae covered with a layer of wax, creating a nanoscale air gap that makes it difficult for water droplets to remain on the leaf surface, thus achieving high superhydrophobicity. Examples of superhydrophobic materials for food packaging already developed using nature as inspiration are listed below, grouped by “source of inspiration”:
- Inspired by swan feathers, films made from carboxymethylcellulose, polyvinyl alcohol, and carnauba wax have been developed. These films have a water contact angle of 138°, similar to feathers, extending the shelf life of pork to 5 days, compared to 2 days for traditional packaging.
- Inspired by lotus leaves, konjac glucomannan fibers, polylactic acid, and tea polyphenols have a water contact angle greater than 150°, thus extending the shelf life of cabbage to 6 days and potatoes to 10 days.
Other films that share the same inspiration are films based on soybean polysaccharides and carnauba wax, which have a water contact angle of 157° and extend the shelf life of grapes to 7 days. Finally, superhydrophobic coatings have been prepared with edible beeswax, gum arabic, and gelatin, which mimic the surface of lotus leaves and have a contact angle greater than 150°. These coatings can be applied by simple spraying, which does not cause any toxicity or leave any volatile organic solvent residue. Surprisingly, these coatings applied to polypropylene containers maintain their excellent superhydrophobicity even after being immersed in hot aqueous solutions (70°C):
- Inspired by rose petals, the films made of starch nanofibers and tannins exhibit a water contact angle of approximately 134° and can extend the shelf life of cherry tomatoes to 15 days, compared to the 8 days of traditional packaging.
- Inspired by duck feathers, the films made with carboxymethylcellulose, gelatin, and candelilla wax exhibit a water contact angle of 142° and extend the shelf life of beef to 5 days, 2 days longer than standard polyethylene packaging.
In addition to the biomaterials already produced, researchers are also mimicking other sensory functions to develop new functional materials:
- Inspired by the thermal regulation of polar bears and penguins, the development of new thermal insulation materials is foreseeable;
- Mosquito eyes are important reference objects for the development of efficient anti-fog packaging;
- The water management strategies of plants such as cacti offer new perspectives for conservation technologies;
- The highly adaptive sensory mechanisms observed in living organisms offer new insights for advances in food packaging. Examples such as Venus flytrap hairs and mammalian whisker systems highlight intriguing sensory perception capabilities.
In conclusion, the future of food packaging promises to be smarter, more eco-friendly, and more versatile. Nature, as an inexhaustible source of inspiration, will continue to guide us towards more sustainable and efficient packaging solutions. Nature-inspired strategies not only focus on improving material performance but also introduce innovative concepts that inspire researchers to develop diverse, cutting-edge solutions. Despite the progress already made, the industrial production of these materials still faces several challenges, including high costs, complex preparation processes, and poor durability due to the delicate surfaces of these materials, susceptible to damage from environmental factors such as temperature, pH, and ultraviolet rays. All of these challenges will gradually be overcome thanks to technological and research advances.
Bibliographic references: S. Hu et al., Foods 14, 2025, 1661.
